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bac0a9e5 |
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08-Feb-2024 |
Christian Brauner <brauner@kernel.org> |
file: add alloc_file_pseudo_noaccount() When we open block devices as files we want to make sure to not charge them against the open file limit of the caller as that can cause spurious failures. Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
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0873add0 |
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08-Feb-2024 |
Christian Brauner <brauner@kernel.org> |
file: prepare for new helper In order to add a helper to open files that aren't accounted split alloc_file() and parts of alloc_file_pseudo() into helpers. One to prepare a path, another one to setup the file. Suggested-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240129160241.GA2793@lst.de Signed-off-by: Christian Brauner <brauner@kernel.org>
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cd3cec0a |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
ima: Move to LSM infrastructure Move hardcoded IMA function calls (not appraisal-specific functions) from various places in the kernel to the LSM infrastructure, by introducing a new LSM named 'ima' (at the end of the LSM list and always enabled like 'integrity'). Having IMA before EVM in the Makefile is sufficient to preserve the relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM, and thus the order of IMA and EVM function calls as when they were hardcoded. Make moved functions as static (except ima_post_key_create_or_update(), which is not in ima_main.c), and register them as implementation of the respective hooks in the new function init_ima_lsm(). Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook path_post_mknod is always available and ima_post_path_mknod() is always executed to mark files as new, as before the move. A slight difference is that IMA and EVM functions registered for the inode_post_setattr, inode_post_removexattr, path_post_mknod, inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl won't be executed for private inodes. Since those inodes are supposed to be fs-internal, they should not be of interest to IMA or EVM. The S_PRIVATE flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub and kernel-internal tmpfs files. Conditionally register ima_post_key_create_or_update() if CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled. Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Chuck Lever <chuck.lever@oracle.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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f09068b5 |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
security: Introduce file_release hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the file_release hook. IMA calculates at file close the new digest of the file content and writes it to security.ima, so that appraisal at next file access succeeds. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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9024b4c9 |
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11-Nov-2023 |
Al Viro <viro@zeniv.linux.org.uk> |
d_alloc_pseudo(): move setting ->d_op there from the (sole) caller Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
9d5b9475 |
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20-Nov-2023 |
Joel Granados <j.granados@samsung.com> |
fs: Remove the now superfluous sentinel elements from ctl_table array This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove sentinel elements ctl_table struct. Special attention was placed in making sure that an empty directory for fs/verity was created when CONFIG_FS_VERITY_BUILTIN_SIGNATURES is not defined. In this case we use the register sysctl call that expects a size. Signed-off-by: Joel Granados <j.granados@samsung.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
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372a34e6 |
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30-Nov-2023 |
Christian Brauner <brauner@kernel.org> |
fs: replace f_rcuhead with f_task_work The naming is actively misleading since we switched to SLAB_TYPESAFE_BY_RCU. rcu_head is #define callback_head. Use callback_head directly and rename f_rcuhead to f_task_work. Add comments in there to explain what it's used for. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-3-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christian Brauner <brauner@kernel.org>
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7cb537b6 |
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25-Nov-2023 |
Al Viro <viro@zeniv.linux.org.uk> |
file: massage cleanup of files that failed to open A file that has never gotten FMODE_OPENED will never have RCU-accessed references, its final fput() is equivalent to file_free() and if it doesn't have FMODE_BACKING either, it can be done from any context and won't need task_work treatment. Now that we have SLAB_TYPESAFE_BY_RCU we can simplify this and have other callers benefit. All of that can be achieved easier is to make fput() recoginze that case and call file_free() directly. No need to introduce a special primitive for that. It also allowed things like failing dentry_open() could benefit from that as well. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [Christian Brauner <brauner@kernel.org>: massage commit message] Link: https://lore.kernel.org/r/20231126020834.GC38156@ZenIV Signed-off-by: Christian Brauner <brauner@kernel.org>
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68279f9c |
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11-Oct-2023 |
Alexey Dobriyan <adobriyan@gmail.com> |
treewide: mark stuff as __ro_after_init __read_mostly predates __ro_after_init. Many variables which are marked __read_mostly should have been __ro_after_init from day 1. Also, mark some stuff as "const" and "__init" while I'm at it. [akpm@linux-foundation.org: revert sysctl_nr_open_min, sysctl_nr_open_max changes due to arm warning] [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/4f6bb9c0-abba-4ee4-a7aa-89265e886817@p183 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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def3ae83 |
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09-Oct-2023 |
Amir Goldstein <amir73il@gmail.com> |
fs: store real path instead of fake path in backing file f_path A backing file struct stores two path's, one "real" path that is referring to f_inode and one "fake" path, which should be displayed to users in /proc/<pid>/maps. There is a lot more potential code that needs to know the "real" path, then code that needs to know the "fake" path. Instead of code having to request the "real" path with file_real_path(), store the "real" path in f_path and require code that needs to know the "fake" path request it with file_user_path(). Replace the file_real_path() helper with a simple const accessor f_path(). After this change, file_dentry() is not expected to observe any files with overlayfs f_path and real f_inode, so the call to ->d_real() should not be needed. Leave the ->d_real() call for now and add an assertion in ovl_d_real() to catch if we made wrong assumptions. Suggested-by: Miklos Szeredi <miklos@szeredi.hu> Link: https://lore.kernel.org/r/CAJfpegtt48eXhhjDFA1ojcHPNKj3Go6joryCPtEFAKpocyBsnw@mail.gmail.com/ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231009153712.1566422-4-amir73il@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
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6cf41fcf |
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05-Oct-2023 |
Christian Brauner <brauner@kernel.org> |
backing file: free directly Backing files as used by overlayfs are never installed into file descriptor tables and are explicitly documented as such. They aren't subject to rcu access conditions like regular files are. Their lifetime is bound to the lifetime of the overlayfs file, i.e., they're stashed in ovl_file->private_data and go away otherwise. If they're set as vma->vm_file - which is their main purpose - then they're subject to regular refcount rules and vma->vm_file can't be installed into an fdtable after having been set. All in all I don't see any need for rcu delay here. So free it directly. This all hinges on such hybrid beasts to never actually be installed into fdtables which - as mentioned before - is not allowed. So add an explicit WARN_ON_ONCE() so we catch any case where someone is suddenly trying to install one of those things into a file descriptor table so we can have a nice long chat with them. Link: https://lore.kernel.org/r/20231005-sakralbau-wappnen-f5c31755ed70@brauner Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
0ede61d8 |
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29-Sep-2023 |
Christian Brauner <brauner@kernel.org> |
file: convert to SLAB_TYPESAFE_BY_RCU In recent discussions around some performance improvements in the file handling area we discussed switching the file cache to rely on SLAB_TYPESAFE_BY_RCU which allows us to get rid of call_rcu() based freeing for files completely. This is a pretty sensitive change overall but it might actually be worth doing. The main downside is the subtlety. The other one is that we should really wait for Jann's patch to land that enables KASAN to handle SLAB_TYPESAFE_BY_RCU UAFs. Currently it doesn't but a patch for this exists. With SLAB_TYPESAFE_BY_RCU objects may be freed and reused multiple times which requires a few changes. So it isn't sufficient anymore to just acquire a reference to the file in question under rcu using atomic_long_inc_not_zero() since the file might have already been recycled and someone else might have bumped the reference. In other words, callers might see reference count bumps from newer users. For this reason it is necessary to verify that the pointer is the same before and after the reference count increment. This pattern can be seen in get_file_rcu() and __files_get_rcu(). In addition, it isn't possible to access or check fields in struct file without first aqcuiring a reference on it. Not doing that was always very dodgy and it was only usable for non-pointer data in struct file. With SLAB_TYPESAFE_BY_RCU it is necessary that callers first acquire a reference under rcu or they must hold the files_lock of the fdtable. Failing to do either one of this is a bug. Thanks to Jann for pointing out that we need to ensure memory ordering between reallocations and pointer check by ensuring that all subsequent loads have a dependency on the second load in get_file_rcu() and providing a fixup that was folded into this patch. Cc: Jann Horn <jannh@google.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
93faf426 |
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26-Sep-2023 |
Mateusz Guzik <mjguzik@gmail.com> |
vfs: shave work on failed file open Failed opens (mostly ENOENT) legitimately happen a lot, for example here are stats from stracing kernel build for few seconds (strace -fc make): % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ------------------ 0.76 0.076233 5 15040 3688 openat (this is tons of header files tried in different paths) In the common case of there being nothing to close (only the file object to free) there is a lot of overhead which can be avoided. This is most notably delegation of freeing to task_work, which comes with an enormous cost (see 021a160abf62 ("fs: use __fput_sync in close(2)" for an example). Benchmarked with will-it-scale with a custom testcase based on tests/open1.c, stuffed into tests/openneg.c: [snip] while (1) { int fd = open("/tmp/nonexistent", O_RDONLY); assert(fd == -1); (*iterations)++; } [/snip] Sapphire Rapids, openneg_processes -t 1 (ops/s): before: 1950013 after: 2914973 (+49%) file refcount is checked as a safety belt against buggy consumers with an atomic cmpxchg. Technically it is not necessary, but it happens to not be measurable due to several other atomics which immediately follow. Optmizing them away to make this atomic into a problem is left as an exercise for the reader. v2: - unexport fput_badopen and move to fs/internal.h - handle the refcount with cmpxchg, adjust commentary accordingly - tweak the commit message Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://lore.kernel.org/r/20230926162228.68666-1-mjguzik@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
021a160a |
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08-Aug-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
fs: use __fput_sync in close(2) close(2) is a special case which guarantees a shallow kernel stack, making delegation to task_work machinery unnecessary. Said delegation is problematic as it involves atomic ops and interrupt masking trips, none of which are cheap on x86-64. Forcing close(2) to do it looks like an oversight in the original work. Moreover presence of CONFIG_RSEQ adds an additional overhead as fput() -> task_work_add(..., TWA_RESUME) -> set_notify_resume() makes the thread returning to userspace land in resume_user_mode_work(), where rseq_handle_notify_resume takes a SMAP round-trip if rseq is enabled for the thread (and it is by default with contemporary glibc). Sample result when benchmarking open1_processes -t 1 from will-it-scale (that's an open + close loop) + tmpfs on /tmp, running on the Sapphire Rapid CPU (ops/s): stock+RSEQ: 1329857 stock-RSEQ: 1421667 (+7%) patched: 1523521 (+14.5% / +7%) (with / without rseq) Patched result is the same regardless of rseq as the codepath is avoided. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
dff745c1 |
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01-Jul-2023 |
Amir Goldstein <amir73il@gmail.com> |
fs: move cleanup from init_file() into its callers The use of file_free_rcu() in init_file() to free the struct that was allocated by the caller was hacky and we got what we deserved. Let init_file() and its callers take care of cleaning up each after their own allocated resources on error. Fixes: 62d53c4a1dfe ("fs: use backing_file container for internal files with "fake" f_path") # mainline only Reported-and-tested-by: syzbot+ada42aab05cf51b00e98@syzkaller.appspotmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Message-Id: <20230701171134.239409-1-amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
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62d53c4a |
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15-Jun-2023 |
Amir Goldstein <amir73il@gmail.com> |
fs: use backing_file container for internal files with "fake" f_path Overlayfs uses open_with_fake_path() to allocate internal kernel files, with a "fake" path - whose f_path is not on the same fs as f_inode. Allocate a container struct backing_file for those internal files, that is used to hold the "fake" ovl path along with the real path. backing_file_real_path() can be used to access the stored real path. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Message-Id: <20230615112229.2143178-5-amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
8a05a8c3 |
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15-Jun-2023 |
Amir Goldstein <amir73il@gmail.com> |
fs: move kmem_cache_zalloc() into alloc_empty_file*() helpers Use a common helper init_file() instead of __alloc_file() for alloc_empty_file*() helpers and improrve the documentation. This is needed for a follow up patch that allocates a backing_file container. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Message-Id: <20230615112229.2143178-4-amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
5970e15d |
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20-Nov-2022 |
Jeff Layton <jlayton@kernel.org> |
filelock: move file locking definitions to separate header file The file locking definitions have lived in fs.h since the dawn of time, but they are only used by a small subset of the source files that include it. Move the file locking definitions to a new header file, and add the appropriate #include directives to the source files that need them. By doing this we trim down fs.h a bit and limit the amount of rebuilding that has to be done when we make changes to the file locking APIs. Reviewed-by: Xiubo Li <xiubli@redhat.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Chuck Lever <chuck.lever@oracle.com> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Acked-by: Steve French <stfrench@microsoft.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jeff Layton <jlayton@kernel.org>
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d6da19c9 |
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16-Aug-2022 |
Amir Goldstein <amir73il@gmail.com> |
locks: fix TOCTOU race when granting write lease Thread A trying to acquire a write lease checks the value of i_readcount and i_writecount in check_conflicting_open() to verify that its own fd is the only fd referencing the file. Thread B trying to open the file for read will call break_lease() in do_dentry_open() before incrementing i_readcount, which leaves a small window where thread A can acquire the write lease and then thread B completes the open of the file for read without breaking the write lease that was acquired by thread A. Fix this race by incrementing i_readcount before checking for existing leases, same as the case with i_writecount. Use a helper put_file_access() to decrement i_readcount or i_writecount in do_dentry_open() and __fput(). Fixes: 387e3746d01c ("locks: eliminate false positive conflicts for write lease") Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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868941b1 |
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29-Jun-2022 |
Jason A. Donenfeld <Jason@zx2c4.com> |
fs: remove no_llseek Now that all callers of ->llseek are going through vfs_llseek(), we don't gain anything by keeping no_llseek around. Nothing actually calls it and setting ->llseek to no_lseek is completely equivalent to leaving it NULL. Longer term (== by the end of merge window) we want to remove all such intializations. To simplify the merge window this commit does *not* touch initializers - it only defines no_llseek as NULL (and simplifies the tests on file opening). At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\<no_llseek\>/d' $i done would do it. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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e7478158 |
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29-Jun-2022 |
Jason A. Donenfeld <Jason@zx2c4.com> |
fs: clear or set FMODE_LSEEK based on llseek function Pipe-like behaviour on llseek(2) (i.e. unconditionally failing with -ESPIPE) can be expresses in 3 ways: 1) ->llseek set to NULL in file_operations 2) ->llseek set to no_llseek in file_operations 3) FMODE_LSEEK *not* set in ->f_mode. Enforce (3) in cases (1) and (2); that will allow to simplify the checks and eventually get rid of no_llseek boilerplate. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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164f4064 |
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22-May-2022 |
Al Viro <viro@zeniv.linux.org.uk> |
keep iocb_flags() result cached in struct file * calculate at the time we set FMODE_OPENED (do_dentry_open() for normal opens, alloc_file() for pipe()/socket()/etc.) * update when handling F_SETFL * keep in a new field - file->f_iocb_flags; since that thing is needed only before the refcount reaches zero, we can put it into the same anon union where ->f_rcuhead and ->f_llist live - those are used only after refcount reaches zero. Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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e87f2c26 |
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22-May-2022 |
Al Viro <viro@zeniv.linux.org.uk> |
struct file: use anonymous union member for rcuhead and llist Once upon a time we couldn't afford anon unions; these days minimal gcc version had been raised enough to take care of that. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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81132a39 |
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01-Nov-2021 |
Gou Hao <gouhao@uniontech.com> |
fs: remove fget_many and fput_many interface These two interface were added in 091141a42 commit, but now there is no place to call them. The only user of fput/fget_many() was removed in commit 62906e89e63b ("io_uring: remove file batch-get optimisation"). A user of get_file_rcu_many() were removed in commit f073531070d2 ("init: add an init_dup helper"). And replace atomic_long_sub/add to atomic_long_dec/inc can improve performance. Here are the test results of unixbench: Cmd: ./Run -c 64 context1 Without patch: System Benchmarks Partial Index BASELINE RESULT INDEX Pipe-based Context Switching 4000.0 2798407.0 6996.0 ======== System Benchmarks Index Score (Partial Only) 6996.0 With patch: System Benchmarks Partial Index BASELINE RESULT INDEX Pipe-based Context Switching 4000.0 3486268.8 8715.7 ======== System Benchmarks Index Score (Partial Only) 8715.7 Signed-off-by: Gou Hao <gouhao@uniontech.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f0043206 |
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03-Apr-2022 |
Trond Myklebust <trond.myklebust@hammerspace.com> |
SUNRPC: Ensure we flush any closed sockets before xs_xprt_free() We must ensure that all sockets are closed before we call xprt_free() and release the reference to the net namespace. The problem is that calling fput() will defer closing the socket until delayed_fput() gets called. Let's fix the situation by allowing rpciod and the transport teardown code (which runs on the system wq) to call __fput_sync(), and directly close the socket. Reported-by: Felix Fu <foyjog@gmail.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Fixes: a73881c96d73 ("SUNRPC: Fix an Oops in udp_poll()") Cc: stable@vger.kernel.org # 5.1.x: 3be232f11a3c: SUNRPC: Prevent immediate close+reconnect Cc: stable@vger.kernel.org # 5.1.x: 89f42494f92f: SUNRPC: Don't call connect() more than once on a TCP socket Cc: stable@vger.kernel.org # 5.1.x Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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a3580ac9 |
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14-Feb-2022 |
Luis Chamberlain <mcgrof@kernel.org> |
fs/file_table: fix adding missing kmemleak_not_leak() Commit b42bc9a3c511 ("Fix regression due to "fs: move binfmt_misc sysctl to its own file") fixed a regression, however it failed to add a kmemleak_not_leak(). Fixes: b42bc9a3c511 ("Fix regression due to "fs: move binfmt_misc sysctl to its own file") Reported-by: Tong Zhang <ztong0001@gmail.com> Cc: Tong Zhang <ztong0001@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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b42bc9a3 |
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09-Feb-2022 |
Domenico Andreoli <domenico.andreoli@linux.com> |
Fix regression due to "fs: move binfmt_misc sysctl to its own file" Commit 3ba442d5331f ("fs: move binfmt_misc sysctl to its own file") did not go unnoticed, binfmt-support stopped to work on my Debian system since v5.17-rc2 (did not check with -rc1). The existance of the /proc/sys/fs/binfmt_misc is a precondition for attempting to mount the binfmt_misc fs, which in turn triggers the autoload of the binfmt_misc module. Without it, no module is loaded and no binfmt is available at boot. Building as built-in or manually loading the module and mounting the fs works fine, it's therefore only a matter of interaction with user-space. I could try to improve the Debian systemd configuration but I can't say anything about the other distributions. This patch restores a working system right after boot. Fixes: 3ba442d5331f ("fs: move binfmt_misc sysctl to its own file") Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Tong Zhang <ztong0001@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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204d5a24 |
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21-Jan-2022 |
Luis Chamberlain <mcgrof@kernel.org> |
fs: move fs stat sysctls to file_table.c kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain. To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic. We can create the sysctl dynamically on early init for fs stat to help with this clutter. This dusts off the fs stat syctls knobs and puts them into where they are declared. Link: https://lkml.kernel.org/r/20211129205548.605569-3-mcgrof@kernel.org Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Antti Palosaari <crope@iki.fi> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Iurii Zaikin <yzaikin@google.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Jeff Layton <jlayton@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Lukas Middendorf <kernel@tuxforce.de> Cc: Stephen Kitt <steve@sk2.org> Cc: Xiaoming Ni <nixiaoming@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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319c1517 |
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01-Oct-2020 |
Al Viro <viro@zeniv.linux.org.uk> |
epoll: take epitem list out of struct file Move the head of epitem list out of struct file; for epoll ones it's moved into struct eventpoll (->refs there), for non-epoll - into the new object (struct epitem_head). In place of ->f_ep_links we leave a pointer to the list head (->f_ep). ->f_ep is protected by ->f_lock and it's zeroed as soon as the list of epitems becomes empty (that can happen only in ep_remove() by now). The list of files for reverse path check is *not* going through struct file now - it's a single-linked list going through epitem_head instances. It's terminated by ERR_PTR(-1) (== EP_UNACTIVE_POINTER), so the elements of list can be distinguished by head->next != NULL. epitem_head instances are allocated at ep_insert() time (by attach_epitem()) and freed either by ep_remove() (if it empties the set of epitems *and* epitem_head does not belong to the reverse path check list) or by clear_tfile_check_list() when the list is emptied (if the set of epitems is empty by that point). Allocations are done from a separate slab - minimal kmalloc() size is too large on some architectures. As the result, we trim struct file _and_ get rid of the games with temporary file references. Locking and barriers are interesting (aren't they always); see unlist_file() and ep_remove() for details. The non-obvious part is that ep_remove() needs to decide if it will be the one to free the damn thing *before* actually storing NULL to head->epitems.first - that's what smp_load_acquire is for in there. unlist_file() lockless path is safe, since we hit it only if we observe NULL in head->epitems.first and whoever had done that store is guaranteed to have observed non-NULL in head->next. IOW, their last access had been the store of NULL into ->epitems.first and we can safely free the sucker. OTOH, we are under rcu_read_lock() and both epitem and epitem->file have their freeing RCU-delayed. So if we see non-NULL ->epitems.first, we can grab ->f_lock (all epitems in there share the same struct file) and safely recheck the emptiness of ->epitems; again, ->next is still non-NULL, so ep_remove() couldn't have freed head yet. ->f_lock serializes us wrt ep_remove(); the rest is trivial. Note that once head->epitems becomes NULL, nothing can get inserted into it - the only remaining reference to head after that point is from the reverse path check list. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
91989c70 |
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16-Oct-2020 |
Jens Axboe <axboe@kernel.dk> |
task_work: cleanup notification modes A previous commit changed the notification mode from true/false to an int, allowing notify-no, notify-yes, or signal-notify. This was backwards compatible in the sense that any existing true/false user would translate to either 0 (on notification sent) or 1, the latter which mapped to TWA_RESUME. TWA_SIGNAL was assigned a value of 2. Clean this up properly, and define a proper enum for the notification mode. Now we have: - TWA_NONE. This is 0, same as before the original change, meaning no notification requested. - TWA_RESUME. This is 1, same as before the original change, meaning that we use TIF_NOTIFY_RESUME. - TWA_SIGNAL. This uses TIF_SIGPENDING/JOBCTL_TASK_WORK for the notification. Clean up all the callers, switching their 0/1/false/true to using the appropriate TWA_* mode for notifications. Fixes: e91b48162332 ("task_work: teach task_work_add() to do signal_wake_up()") Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
b6509f6a |
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29-Jun-2020 |
Mel Gorman <mgorman@techsingularity.net> |
Revert "fs: Do not check if there is a fsnotify watcher on pseudo inodes" This reverts commit e9c15badbb7b ("fs: Do not check if there is a fsnotify watcher on pseudo inodes"). The commit intended to eliminate fsnotify-related overhead for pseudo inodes but it is broken in concept. inotify can receive events of pipe files under /proc/X/fd and chromium relies on close and open events for sandboxing. Maxim Levitsky reported the following Chromium starts as a white rectangle, shows few white rectangles that resemble its notifications and then crashes. The stdout output from chromium: [mlevitsk@starship ~]$chromium-freeworld mesa: for the --simplifycfg-sink-common option: may only occur zero or one times! mesa: for the --global-isel-abort option: may only occur zero or one times! [3379:3379:0628/135151.440930:ERROR:browser_switcher_service.cc(238)] XXX Init() ../../sandbox/linux/seccomp-bpf-helpers/sigsys_handlers.cc:**CRASHING**:seccomp-bpf failure in syscall 0072 Received signal 11 SEGV_MAPERR 0000004a9048 Crashes are not universal but even if chromium does not crash, it certainly does not work properly. While filtering just modify and access might be safe, the benefit is not worth the risk hence the revert. Reported-by: Maxim Levitsky <mlevitsk@redhat.com> Fixes: e9c15badbb7b ("fs: Do not check if there is a fsnotify watcher on pseudo inodes") Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
e9c15bad |
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15-Jun-2020 |
Mel Gorman <mgorman@techsingularity.net> |
fs: Do not check if there is a fsnotify watcher on pseudo inodes The kernel uses internal mounts created by kern_mount() and populated with files with no lookup path by alloc_file_pseudo() for a variety of reasons. An example of such a mount is for anonymous pipes. For pipes, every vfs_write() regardless of filesystem, calls fsnotify_modify() to notify of any changes which incurs a small amount of overhead in fsnotify even when there are no watchers. It can also trigger for reads and readv and writev, it was simply vfs_write() that was noticed first. A patch is pending that reduces, but does not eliminate, the overhead of fsnotify but for files that cannot be looked up via a path, even that small overhead is unnecessary. The user API for all notification subsystems (inotify, fanotify, ...) is based on the pathname and a dirfd and proc entries appear to be the only visible representation of the files. Proc does not have the same pathname as the internal entry and the proc inode is not the same as the internal inode so even if fanotify is used on a file under /proc/XX/fd, no useful events are notified. This patch changes alloc_file_pseudo() to always opt out of fsnotify by setting FMODE_NONOTIFY flag so that no check is made for fsnotify watchers on pseudo files. This should be safe as the underlying helper for the dentry is d_alloc_pseudo() which explicitly states that no lookups are ever performed meaning that fanotify should have nothing useful to attach to. The test motivating this was "perf bench sched messaging --pipe". On a single-socket machine using threads the difference of the patch was as follows. 5.7.0 5.7.0 vanilla nofsnotify-v1r1 Amean 1 1.3837 ( 0.00%) 1.3547 ( 2.10%) Amean 3 3.7360 ( 0.00%) 3.6543 ( 2.19%) Amean 5 5.8130 ( 0.00%) 5.7233 * 1.54%* Amean 7 8.1490 ( 0.00%) 7.9730 * 2.16%* Amean 12 14.6843 ( 0.00%) 14.1820 ( 3.42%) Amean 18 21.8840 ( 0.00%) 21.7460 ( 0.63%) Amean 24 28.8697 ( 0.00%) 29.1680 ( -1.03%) Amean 30 36.0787 ( 0.00%) 35.2640 * 2.26%* Amean 32 38.0527 ( 0.00%) 38.1223 ( -0.18%) The difference is small but in some cases it's outside the noise so while marginal, there is still some small benefit to ignoring fsnotify for files allocated via alloc_file_pseudo() in some cases. Link: https://lore.kernel.org/r/20200615121358.GF3183@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
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#
735e4ae5 |
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01-Jun-2020 |
Jeff Layton <jlayton@kernel.org> |
vfs: track per-sb writeback errors and report them to syncfs Patch series "vfs: have syncfs() return error when there are writeback errors", v6. Currently, syncfs does not return errors when one of the inodes fails to be written back. It will return errors based on the legacy AS_EIO and AS_ENOSPC flags when syncing out the block device fails, but that's not particularly helpful for filesystems that aren't backed by a blockdev. It's also possible for a stray sync to lose those errors. The basic idea in this set is to track writeback errors at the superblock level, so that we can quickly and easily check whether something bad happened without having to fsync each file individually. syncfs is then changed to reliably report writeback errors after they occur, much in the same fashion as fsync does now. This patch (of 2): Usually we suggest that applications call fsync when they want to ensure that all data written to the file has made it to the backing store, but that can be inefficient when there are a lot of open files. Calling syncfs on the filesystem can be more efficient in some situations, but the error reporting doesn't currently work the way most people expect. If a single inode on a filesystem reports a writeback error, syncfs won't necessarily return an error. syncfs only returns an error if __sync_blockdev fails, and on some filesystems that's a no-op. It would be better if syncfs reported an error if there were any writeback failures. Then applications could call syncfs to see if there are any errors on any open files, and could then call fsync on all of the other descriptors to figure out which one failed. This patch adds a new errseq_t to struct super_block, and has mapping_set_error also record writeback errors there. To report those errors, we also need to keep an errseq_t in struct file to act as a cursor. This patch adds a dedicated field for that purpose, which slots nicely into 4 bytes of padding at the end of struct file on x86_64. An earlier version of this patch used an O_PATH file descriptor to cue the kernel that the open file should track the superblock error and not the inode's writeback error. I think that API is just too weird though. This is simpler and should make syncfs error reporting "just work" even if someone is multiplexing fsync and syncfs on the same fds. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Andres Freund <andres@anarazel.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: David Howells <dhowells@redhat.com> Link: http://lkml.kernel.org/r/20200428135155.19223-1-jlayton@kernel.org Link: http://lkml.kernel.org/r/20200428135155.19223-2-jlayton@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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32927393 |
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24-Apr-2020 |
Christoph Hellwig <hch@lst.de> |
sysctl: pass kernel pointers to ->proc_handler Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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7239a40c |
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18-Aug-2019 |
Trond Myklebust <trond.myklebust@primarydata.com> |
vfs: Export flush_delayed_fput for use by knfsd. Allow knfsd to flush the delayed fput list so that it can ensure the cached struct file is closed before it is unlinked. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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457c8996 |
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19-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Add SPDX license identifier for missed files Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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a07b2000 |
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05-Nov-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
vfs: syscall: Add open_tree(2) to reference or clone a mount open_tree(dfd, pathname, flags) Returns an O_PATH-opened file descriptor or an error. dfd and pathname specify the location to open, in usual fashion (see e.g. fstatat(2)). flags should be an OR of some of the following: * AT_PATH_EMPTY, AT_NO_AUTOMOUNT, AT_SYMLINK_NOFOLLOW - same meanings as usual * OPEN_TREE_CLOEXEC - make the resulting descriptor close-on-exec * OPEN_TREE_CLONE or OPEN_TREE_CLONE | AT_RECURSIVE - instead of opening the location in question, create a detached mount tree matching the subtree rooted at location specified by dfd/pathname. With AT_RECURSIVE the entire subtree is cloned, without it - only the part within in the mount containing the location in question. In other words, the same as mount --rbind or mount --bind would've taken. The detached tree will be dissolved on the final close of obtained file. Creation of such detached trees requires the same capabilities as doing mount --bind. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-api@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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091141a4 |
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21-Nov-2018 |
Jens Axboe <axboe@kernel.dk> |
fs: add fget_many() and fput_many() Some uses cases repeatedly get and put references to the same file, but the only exposed interface is doing these one at the time. As each of these entail an atomic inc or dec on a shared structure, that cost can add up. Add fget_many(), which works just like fget(), except it takes an argument for how many references to get on the file. Ditto fput_many(), which can drop an arbitrary number of references to a file. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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ca79b0c2 |
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28-Dec-2018 |
Arun KS <arunks@codeaurora.org> |
mm: convert totalram_pages and totalhigh_pages variables to atomic totalram_pages and totalhigh_pages are made static inline function. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. [akpm@linux-foundation.org: coding style fixes] Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Suggested-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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3d6357de |
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28-Dec-2018 |
Arun KS <arunks@codeaurora.org> |
mm: reference totalram_pages and managed_pages once per function Patch series "mm: convert totalram_pages, totalhigh_pages and managed pages to atomic", v5. This series converts totalram_pages, totalhigh_pages and zone->managed_pages to atomic variables. totalram_pages, zone->managed_pages and totalhigh_pages updates are protected by managed_page_count_lock, but readers never care about it. Convert these variables to atomic to avoid readers potentially seeing a store tear. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better to remove the lock and convert variables to atomic. With the change, preventing poteintial store-to-read tearing comes as a bonus. This patch (of 4): This is in preparation to a later patch which converts totalram_pages and zone->managed_pages to atomic variables. Please note that re-reading the value might lead to a different value and as such it could lead to unexpected behavior. There are no known bugs as a result of the current code but it is better to prevent from them in principle. Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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d3b1084d |
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18-Jul-2018 |
Miklos Szeredi <mszeredi@redhat.com> |
vfs: make open_with_fake_path() not contribute to nr_files Stacking file operations in overlay will store an extra open file for each overlay file opened. The overhead is just that of "struct file" which is about 256bytes, because overlay already pins an extra dentry and inode when the file is open, which add up to a much larger overhead. For fear of breaking working setups, don't start accounting the extra file. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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ee1904ba |
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17-Jun-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
make alloc_file() static Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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183266f2 |
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17-Jun-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
new helper: alloc_file_clone() alloc_file_clone(old_file, mode, ops): create a new struct file with ->f_path equal to that of old_file. pipe converted. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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d93aa9d8 |
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09-Jun-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
new wrapper: alloc_file_pseudo() takes inode, vfsmount, name, O_... flags and file_operations and either returns a new struct file (in which case inode reference we held is consumed) or returns ERR_PTR(), in which case no refcounts are altered. converted aio_private_file() and sock_alloc_file() to it Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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4d27f326 |
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09-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
fold put_filp() into fput() Just check FMODE_OPENED in __fput() and be done with that... Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f5d11409 |
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09-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
introduce FMODE_OPENED basically, "is that instance set up enough for regular fput(), or do we want put_filp() for that one". NOTE: the only alloc_file() caller that could be followed by put_filp() is in arch/ia64/kernel/perfmon.c, which is (Kconfig-level) broken. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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ea73ea72 |
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11-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
pass ->f_flags value to alloc_empty_file() ... and have it set the f_flags-derived part of ->f_mode. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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6de37b6d |
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10-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
pass creds to get_empty_filp(), make sure dentry_open() passes the right creds ... and rename get_empty_filp() to alloc_empty_file(). dentry_open() gets creds as argument, but the only thing that sees those is security_file_open() - file->f_cred still ends up with current_cred(). For almost all callers it's the same thing, but there are several broken cases. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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c9c554f2 |
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11-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
alloc_file(): switch to passing O_... flags instead of FMODE_... mode ... so that it could set both ->f_flags and ->f_mode, without callers having to set ->f_flags manually. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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e8cff84f |
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09-Jul-2018 |
Al Viro <viro@zeniv.linux.org.uk> |
fold security_file_free() into file_free() .. and the call of file_free() in case of security_file_alloc() failure in get_empty_filp() should be simply file_free_rcu() - no point in rcu-delays there, anyway. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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9c565035 |
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17-Nov-2017 |
Yang Shi <yang.s@alibaba-inc.com> |
vfs: remove unused hardirq.h Preempt counter APIs have been split out, currently, hardirq.h just includes irq_enter/exit APIs which are not used by vfs at all. So, remove the unused hardirq.h. Signed-off-by: Yang Shi <yang.s@alibaba-inc.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f3f7c093 |
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15-Nov-2017 |
Shakeel Butt <shakeelb@google.com> |
fs, mm: account filp cache to kmemcg The allocations from filp cache can be directly triggered by userspace applications. A buggy application can consume a significant amount of unaccounted system memory. Though we have not noticed such buggy applications in our production but upon close inspection, we found that a lot of machines spend very significant amount of memory on these caches. One way to limit allocations from filp cache is to set system level limit of maximum number of open files. However this limit is shared between different users on the system and one user can hog this resource. To cater that, we can charge filp to kmemcg and set the maximum limit very high and let the memory limit of each user limit the number of files they can open and indirectly limiting their allocations from filp cache. One side effect of this change is that it will allow _sysctl() to return ENOMEM and the man page of _sysctl() does not specify that. However the man page also discourages to use _sysctl() at all. Link: http://lkml.kernel.org/r/20171011190359.34926-1-shakeelb@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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bb02b186 |
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21-Jun-2017 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
ima: call ima_file_free() prior to calling fasync The file hash is calculated and written out as an xattr after calling fasync(). In order for the file data and metadata to be written out to disk at the same time, this patch calculates the file hash and stores it as an xattr before calling fasync. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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b9ea557e |
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07-Aug-2017 |
Byungchul Park <byungchul.park@lge.com> |
fput: Don't reinvent the wheel but use existing llist API Although llist provides proper APIs, they are not used. Make them used. Signed-off-by: Byungchul Park <byungchul.park@lge.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
5660e13d |
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06-Jul-2017 |
Jeff Layton <jlayton@kernel.org> |
fs: new infrastructure for writeback error handling and reporting Most filesystems currently use mapping_set_error and filemap_check_errors for setting and reporting/clearing writeback errors at the mapping level. filemap_check_errors is indirectly called from most of the filemap_fdatawait_* functions and from filemap_write_and_wait*. These functions are called from all sorts of contexts to wait on writeback to finish -- e.g. mostly in fsync, but also in truncate calls, getattr, etc. The non-fsync callers are problematic. We should be reporting writeback errors during fsync, but many places spread over the tree clear out errors before they can be properly reported, or report errors at nonsensical times. If I get -EIO on a stat() call, there is no reason for me to assume that it is because some previous writeback failed. The fact that it also clears out the error such that a subsequent fsync returns 0 is a bug, and a nasty one since that's potentially silent data corruption. This patch adds a small bit of new infrastructure for setting and reporting errors during address_space writeback. While the above was my original impetus for adding this, I think it's also the case that current fsync semantics are just problematic for userland. Most applications that call fsync do so to ensure that the data they wrote has hit the backing store. In the case where there are multiple writers to the file at the same time, this is really hard to determine. The first one to call fsync will see any stored error, and the rest get back 0. The processes with open fds may not be associated with one another in any way. They could even be in different containers, so ensuring coordination between all fsync callers is not really an option. One way to remedy this would be to track what file descriptor was used to dirty the file, but that's rather cumbersome and would likely be slow. However, there is a simpler way to improve the semantics here without incurring too much overhead. This set adds an errseq_t to struct address_space, and a corresponding one is added to struct file. Writeback errors are recorded in the mapping's errseq_t, and the one in struct file is used as the "since" value. This changes the semantics of the Linux fsync implementation such that applications can now use it to determine whether there were any writeback errors since fsync(fd) was last called (or since the file was opened in the case of fsync having never been called). Note that those writeback errors may have occurred when writing data that was dirtied via an entirely different fd, but that's the case now with the current mapping_set_error/filemap_check_error infrastructure. This will at least prevent you from getting a false report of success. The new behavior is still consistent with the POSIX spec, and is more reliable for application developers. This patch just adds some basic infrastructure for doing this, and ensures that the f_wb_err "cursor" is properly set when a file is opened. Later patches will change the existing code to use this new infrastructure for reporting errors at fsync time. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz>
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5b825c3a |
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02-Feb-2017 |
Ingo Molnar <mingo@kernel.org> |
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h> Add #include <linux/cred.h> dependencies to all .c files rely on sched.h doing that for them. Note that even if the count where we need to add extra headers seems high, it's still a net win, because <linux/sched.h> is included in over 2,200 files ... Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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a4141d7c |
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20-Nov-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
constify alloc_file() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
4248b0da |
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06-Aug-2015 |
Mel Gorman <mgorman@suse.de> |
fs, file table: reinit files_stat.max_files after deferred memory initialisation Dave Hansen reported the following; My laptop has been behaving strangely with 4.2-rc2. Once I log in to my X session, I start getting all kinds of strange errors from applications and see this in my dmesg: VFS: file-max limit 8192 reached The problem is that the file-max is calculated before memory is fully initialised and miscalculates how much memory the kernel is using. This patch recalculates file-max after deferred memory initialisation. Note that using memory hotplug infrastructure would not have avoided this problem as the value is not recalculated after memory hot-add. 4.1: files_stat.max_files = 6582781 4.2-rc2: files_stat.max_files = 8192 4.2-rc2 patched: files_stat.max_files = 6562467 Small differences with the patch applied and 4.1 but not enough to matter. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Dave Hansen <dave.hansen@intel.com> Cc: Nicolai Stange <nicstange@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Alex Ng <alexng@microsoft.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
e5e6e97f |
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04-Jun-2015 |
Al Viro <viro@zeniv.linux.org.uk> |
remove the pointless include of lglock.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
84363182 |
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03-Apr-2015 |
Al Viro <viro@zeniv.linux.org.uk> |
->aio_read and ->aio_write removed no remaining users Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
a457606a |
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12-Oct-2014 |
Eric Biggers <ebiggers3@gmail.com> |
fs/file_table.c: Update alloc_file() comment This comment is 5 years outdated; init_file() no longer exists. Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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908c7f19 |
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07-Sep-2014 |
Tejun Heo <tj@kernel.org> |
percpu_counter: add @gfp to percpu_counter_init() Percpu allocator now supports allocation mask. Add @gfp to percpu_counter_init() so that !GFP_KERNEL allocation masks can be used with percpu_counters too. We could have left percpu_counter_init() alone and added percpu_counter_init_gfp(); however, the number of users isn't that high and introducing _gfp variants to all percpu data structures would be quite ugly, so let's just do the conversion. This is the one with the most users. Other percpu data structures are a lot easier to convert. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jan Kara <jack@suse.cz> Acked-by: "David S. Miller" <davem@davemloft.net> Cc: x86@kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org>
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#
1f7e0616 |
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06-Jun-2014 |
Joe Perches <joe@perches.com> |
fs: convert use of typedef ctl_table to struct ctl_table This typedef is unnecessary and should just be removed. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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293bc982 |
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11-Feb-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
new methods: ->read_iter() and ->write_iter() Beginning to introduce those. Just the callers for now, and it's clumsier than it'll eventually become; once we finish converting aio_read and aio_write instances, the things will get nicer. For now, these guys are in parallel to ->aio_read() and ->aio_write(); they take iocb and iov_iter, with everything in iov_iter already validated. File offset is passed in iocb->ki_pos, iov/nr_segs - in iov_iter. Main concerns in that series are stack footprint and ability to split the damn thing cleanly. [fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
7f7f25e8 |
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11-Feb-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
replace checking for ->read/->aio_read presence with check in ->f_mode Since we are about to introduce new methods (read_iter/write_iter), the tests in a bunch of places would have to grow inconveniently. Check once (at open() time) and store results in ->f_mode as FMODE_CAN_READ and FMODE_CAN_WRITE resp. It might end up being a temporary measure - once everything switches from ->aio_{read,write} to ->{read,write}_iter it might make sense to return to open-coded checks. We'll see... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
7f4b36f9 |
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13-Mar-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of files_defer_init() the only thing it's doing these days is calculation of upper limit for fs.nr_open sysctl and that can be done statically Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
83f936c7 |
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13-Mar-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
mark struct file that had write access grabbed by open() new flag in ->f_mode - FMODE_WRITER. Set by do_dentry_open() in case when it has grabbed write access, checked by __fput() to decide whether it wants to drop the sucker. Allows to stop bothering with mnt_clone_write() in alloc_file(), along with fewer special_file() checks. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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4597e695 |
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14-Mar-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of DEBUG_WRITECOUNT it only makes control flow in __fput() and friends more convoluted. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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dd20908a |
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14-Mar-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
don't bother with {get,put}_write_access() on non-regular files it's pointless and actually leads to wrong behaviour in at least one moderately convoluted case (pipe(), close one end, try to get to another via /proc/*/fd and run into ETXTBUSY). Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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78ed8a13 |
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02-Feb-2014 |
Jeff Layton <jlayton@kernel.org> |
locks: rename locks_remove_flock to locks_remove_file This function currently removes leases in addition to flock locks and in a later patch we'll have it deal with file-private locks too. Rename it to locks_remove_file to indicate that it removes locks that are associated with a particular struct file, and not just flock locks. Acked-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Jeff Layton <jlayton@redhat.com>
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9c225f26 |
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03-Mar-2014 |
Linus Torvalds <torvalds@linux-foundation.org> |
vfs: atomic f_pos accesses as per POSIX Our write() system call has always been atomic in the sense that you get the expected thread-safe contiguous write, but we haven't actually guaranteed that concurrent writes are serialized wrt f_pos accesses, so threads (or processes) that share a file descriptor and use "write()" concurrently would quite likely overwrite each others data. This violates POSIX.1-2008/SUSv4 Section XSI 2.9.7 that says: "2.9.7 Thread Interactions with Regular File Operations All of the following functions shall be atomic with respect to each other in the effects specified in POSIX.1-2008 when they operate on regular files or symbolic links: [...]" and one of the effects is the file position update. This unprotected file position behavior is not new behavior, and nobody has ever cared. Until now. Yongzhi Pan reported unexpected behavior to Michael Kerrisk that was due to this. This resolves the issue with a f_pos-specific lock that is taken by read/write/lseek on file descriptors that may be shared across threads or processes. Reported-by: Yongzhi Pan <panyongzhi@gmail.com> Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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eee5cc27 |
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04-Oct-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of s_files and files_lock The only thing we need it for is alt-sysrq-r (emergency remount r/o) and these days we can do just as well without going through the list of files. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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72c2d531 |
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22-Sep-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
file->f_op is never NULL... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c7314d74 |
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20-Oct-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
nfsd regression since delayed fput() Background: nfsd v[23] had throughput regression since delayed fput went in; every read or write ends up doing fput() and we get a pair of extra context switches out of that (plus quite a bit of work in queue_work itselfi, apparently). Use of schedule_delayed_work() gives it a chance to accumulate a bit before we do __fput() on all of them. I'm not too happy about that solution, but... on at least one real-world setup it reverts about 10% throughput loss we got from switch to delayed fput. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
be49b30a |
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11-Sep-2013 |
Andrew Morton <akpm@linux-foundation.org> |
fs/file_table.c:fput(): make comment more truthful Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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184cacab |
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30-Aug-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
only regular files with FMODE_WRITE need to be on s_files Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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4f5e65a1 |
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08-Jul-2013 |
Oleg Nesterov <oleg@redhat.com> |
fput: turn "list_head delayed_fput_list" into llist_head fput() and delayed_fput() can use llist and avoid the locking. This is unlikely path, it is not that this change can improve the performance, but this way the code looks simpler. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Vagin <avagin@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: David Howells <dhowells@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
64372501 |
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08-Jul-2013 |
Andrew Morton <akpm@linux-foundation.org> |
fs/file_table.c:fput(): add comment A missed update to "fput: task_work_add() can fail if the caller has passed exit_task_work()". Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Vagin <avagin@openvz.org> Cc: David Howells <dhowells@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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c77cecee |
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13-Jun-2013 |
David Howells <dhowells@redhat.com> |
Replace a bunch of file->dentry->d_inode refs with file_inode() Replace a bunch of file->dentry->d_inode refs with file_inode(). In __fput(), use file->f_inode instead so as not to be affected by any tricks that file_inode() might grow. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
e7b2c406 |
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14-Jun-2013 |
Oleg Nesterov <oleg@redhat.com> |
fput: task_work_add() can fail if the caller has passed exit_task_work() fput() assumes that it can't be called after exit_task_work() but this is not true, for example free_ipc_ns()->shm_destroy() can do this. In this case fput() silently leaks the file. Change it to fallback to delayed_fput_work if task_work_add() fails. The patch looks complicated but it is not, it changes the code from if (PF_KTHREAD) { schedule_work(...); return; } task_work_add(...) to if (!PF_KTHREAD) { if (!task_work_add(...)) return; /* fallback */ } schedule_work(...); As for shm_destroy() in particular, we could make another fix but I think this change makes sense anyway. There could be another similar user, it is not safe to assume that task_work_add() can't fail. Reported-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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dd37978c |
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01-Mar-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
cache the value of file_inode() in struct file Note that this thing does *not* contribute to inode refcount; it's pinned down by dentry. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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39b65252 |
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12-Sep-2012 |
Anatol Pomozov <anatol.pomozov@gmail.com> |
fs: Preserve error code in get_empty_filp(), part 2 Allocating a file structure in function get_empty_filp() might fail because of several reasons: - not enough memory for file structures - operation is not allowed - user is over its limit Currently the function returns NULL in all cases and we loose the exact reason of the error. All callers of get_empty_filp() assume that the function can fail with ENFILE only. Return error through pointer. Change all callers to preserve this error code. [AV: cleaned up a bit, carved the get_empty_filp() part out into a separate commit (things remaining here deal with alloc_file()), removed pipe(2) behaviour change] Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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1afc99be |
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14-Feb-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
propagate error from get_empty_filp() to its callers Based on parts from Anatol's patch (the rest is the next commit). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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496ad9aa |
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23-Jan-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
new helper: file_inode(file) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
72651cac |
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05-Dec-2012 |
Jan Kara <jack@suse.cz> |
fs: Fix imbalance in freeze protection in mark_files_ro() File descriptors (even those for writing) do not hold freeze protection. Thus mark_files_ro() must call __mnt_drop_write() to only drop protection against remount read-only. Calling mnt_drop_write_file() as we do now results in: [ BUG: bad unlock balance detected! ] 3.7.0-rc6-00028-g88e75b6 #101 Not tainted ------------------------------------- kworker/1:2/79 is trying to release lock (sb_writers) at: [<ffffffff811b33b4>] mnt_drop_write+0x24/0x30 but there are no more locks to release! Reported-by: Zdenek Kabelac <zkabelac@redhat.com> CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
4b2c551f |
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09-Oct-2012 |
Lai Jiangshan <laijs@cn.fujitsu.com> |
lglock: add DEFINE_STATIC_LGLOCK() When the lglock doesn't need to be exported we can use DEFINE_STATIC_LGLOCK(). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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0ee8cdfe |
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15-Aug-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
take fget() and friends to fs/file.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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4199d35c |
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16-Mar-2011 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
vfs: move ima_file_free before releasing the file ima_file_free(), called on __fput(), currently flags files that have changed, so that the file is re-measured. For appraising a files's integrity, the file's hash must be re-calculated and stored in the 'security.ima' xattr to reflect any changes. This patch moves the ima_file_free() call to before releasing the file in preparation of ima-appraisal measuring the file and updating the 'security.ima' xattr. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
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eb04c282 |
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12-Jun-2012 |
Jan Kara <jack@suse.cz> |
fs: Add freezing handling to mnt_want_write() / mnt_drop_write() Most of places where we want freeze protection coincides with the places where we also have remount-ro protection. So make mnt_want_write() and mnt_drop_write() (and their _file alternative) prevent freezing as well. For the few cases that are really interested only in remount-ro protection provide new function variants. BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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5c33b183 |
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20-Jul-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
uninline file_free_rcu() What inline? Its only use is passing its address to call_rcu(), for fuck sake! Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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4a9d4b02 |
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23-Jun-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
switch fput to task_work_add ... and schedule_work() for interrupt/kernel_thread callers (and yes, now it *is* OK to call from interrupt). We are guaranteed that __fput() will be done before we return to userland (or exit). Note that for fput() from a kernel thread we get an async behaviour; it's almost always OK, but sometimes you might need to have __fput() completed before you do anything else. There are two mechanisms for that - a general barrier (flush_delayed_fput()) and explicit __fput_sync(). Both should be used with care (as was the case for fput() from kernel threads all along). See comments in fs/file_table.c for details. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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85d7d618 |
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23-Jun-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
mark_files_ro(): don't bother with mntget/mntput mnt_drop_write_file() is safe under any lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
962830df |
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07-May-2012 |
Andi Kleen <ak@linux.intel.com> |
brlocks/lglocks: API cleanups lglocks and brlocks are currently generated with some complicated macros in lglock.h. But there's no reason to not just use common utility functions and put all the data into a common data structure. In preparation, this patch changes the API to look more like normal function calls with pointers, not magic macros. The patch is rather large because I move over all users in one go to keep it bisectable. This impacts the VFS somewhat in terms of lines changed. But no actual behaviour change. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
eea62f83 |
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07-May-2012 |
Andi Kleen <ak@linux.intel.com> |
brlocks/lglocks: turn into functions lglocks and brlocks are currently generated with some complicated macros in lglock.h. But there's no reason to not just use common utility functions and put all the data into a common data structure. Since there are at least two users it makes sense to share this code in a library. This is also easier maintainable than a macro forest. This will also make it later possible to dynamically allocate lglocks and also use them in modules (this would both still need some additional, but now straightforward, code) [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
b57ce969 |
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12-Feb-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
vfs: drop_file_write_access() made static Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
8e8b8796 |
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20-Nov-2011 |
Miklos Szeredi <mszeredi@suse.cz> |
vfs: prevent remount read-only if pending removes If there are any inodes on the super block that have been unlinked (i_nlink == 0) but have not yet been deleted then prevent the remounting the super block read-only. Reported-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
60063497 |
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26-Jul-2011 |
Arun Sharma <asharma@fb.com> |
atomic: use <linux/atomic.h> This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
60ed8cf7 |
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16-Mar-2011 |
Miklos Szeredi <miklos@szeredi.hu> |
fix cdev leak on O_PATH final fput() __fput doesn't need a cdev_put() for O_PATH handles. Signed-off-by: mszeredi@suse.cz Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
326be7b4 |
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13-Mar-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
Allow passing O_PATH descriptors via SCM_RIGHTS datagrams Just need to make sure that AF_UNIX garbage collector won't confuse O_PATHed socket on filesystem for real AF_UNIX opened socket. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
1abf0c71 |
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13-Mar-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
New kind of open files - "location only". New flag for open(2) - O_PATH. Semantics: * pathname is resolved, but the file itself is _NOT_ opened as far as filesystem is concerned. * almost all operations on the resulting descriptors shall fail with -EBADF. Exceptions are: 1) operations on descriptors themselves (i.e. close(), dup(), dup2(), dup3(), fcntl(fd, F_DUPFD), fcntl(fd, F_DUPFD_CLOEXEC, ...), fcntl(fd, F_GETFD), fcntl(fd, F_SETFD, ...)) 2) fcntl(fd, F_GETFL), for a common non-destructive way to check if descriptor is open 3) "dfd" arguments of ...at(2) syscalls, i.e. the starting points of pathname resolution * closing such descriptor does *NOT* affect dnotify or posix locks. * permissions are checked as usual along the way to file; no permission checks are applied to the file itself. Of course, giving such thing to syscall will result in permission checks (at the moment it means checking that starting point of ....at() is a directory and caller has exec permissions on it). fget() and fget_light() return NULL on such descriptors; use of fget_raw() and fget_raw_light() is needed to get them. That protects existing code from dealing with those things. There are two things still missing (they come in the next commits): one is handling of symlinks (right now we refuse to open them that way; see the next commit for semantics related to those) and another is descriptor passing via SCM_RIGHTS datagrams. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
890275b5 |
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02-Nov-2010 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
IMA: maintain i_readcount in the VFS layer ima_counts_get() updated the readcount and invalidated the PCR, as necessary. Only update the i_readcount in the VFS layer. Move the PCR invalidation checks to ima_file_check(), where it belongs. Maintaining the i_readcount in the VFS layer, will allow other subsystems to use i_readcount. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com>
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#
78d29788 |
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04-Feb-2011 |
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> |
CRED: Fix kernel panic upon security_file_alloc() failure. In get_empty_filp() since 2.6.29, file_free(f) is called with f->f_cred == NULL when security_file_alloc() returned an error. As a result, kernel will panic() due to put_cred(NULL) call within RCU callback. Fix this bug by assigning f->f_cred before calling security_file_alloc(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
3bc0ba43 |
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13-Dec-2010 |
Steven Rostedt <srostedt@redhat.com> |
fs: Remove unlikely() from fget_light() There's an unlikely() in fget_light() that assumes the file ref count will be 1. Running the annotate branch profiler on a desktop that is performing daily tasks (running firefox, evolution, xchat and is also part of a distcc farm), it shows that the ref count is not 1 that often. correct incorrect % Function File Line ------- --------- - -------- ---- ---- 1035099358 6209599193 85 fget_light file_table.c 315 Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
518de9b3 |
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26-Oct-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
fs: allow for more than 2^31 files Robin Holt tried to boot a 16TB system and found af_unix was overflowing a 32bit value : <quote> We were seeing a failure which prevented boot. The kernel was incapable of creating either a named pipe or unix domain socket. This comes down to a common kernel function called unix_create1() which does: atomic_inc(&unix_nr_socks); if (atomic_read(&unix_nr_socks) > 2 * get_max_files()) goto out; The function get_max_files() is a simple return of files_stat.max_files. files_stat.max_files is a signed integer and is computed in fs/file_table.c's files_init(). n = (mempages * (PAGE_SIZE / 1024)) / 10; files_stat.max_files = n; In our case, mempages (total_ram_pages) is approx 3,758,096,384 (0xe0000000). That leaves max_files at approximately 1,503,238,553. This causes 2 * get_max_files() to integer overflow. </quote> Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long integers, and change af_unix to use an atomic_long_t instead of atomic_t. get_max_files() is changed to return an unsigned long. get_nr_files() is changed to return a long. unix_nr_socks is changed from atomic_t to atomic_long_t, while not strictly needed to address Robin problem. Before patch (on a 64bit kernel) : # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max -18446744071562067968 After patch: # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max 2147483648 # cat /proc/sys/fs/file-nr 704 0 2147483648 Reported-by: Robin Holt <holt@sgi.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: David Miller <davem@davemloft.net> Reviewed-by: Robin Holt <holt@sgi.com> Tested-by: Robin Holt <holt@sgi.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
7e360c38 |
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05-Oct-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
fs: allow for more than 2^31 files Andrew, Could you please review this patch, you probably are the right guy to take it, because it crosses fs and net trees. Note : /proc/sys/fs/file-nr is a read-only file, so this patch doesnt depend on previous patch (sysctl: fix min/max handling in __do_proc_doulongvec_minmax()) Thanks ! [PATCH V4] fs: allow for more than 2^31 files Robin Holt tried to boot a 16TB system and found af_unix was overflowing a 32bit value : <quote> We were seeing a failure which prevented boot. The kernel was incapable of creating either a named pipe or unix domain socket. This comes down to a common kernel function called unix_create1() which does: atomic_inc(&unix_nr_socks); if (atomic_read(&unix_nr_socks) > 2 * get_max_files()) goto out; The function get_max_files() is a simple return of files_stat.max_files. files_stat.max_files is a signed integer and is computed in fs/file_table.c's files_init(). n = (mempages * (PAGE_SIZE / 1024)) / 10; files_stat.max_files = n; In our case, mempages (total_ram_pages) is approx 3,758,096,384 (0xe0000000). That leaves max_files at approximately 1,503,238,553. This causes 2 * get_max_files() to integer overflow. </quote> Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long integers, and change af_unix to use an atomic_long_t instead of atomic_t. get_max_files() is changed to return an unsigned long. get_nr_files() is changed to return a long. unix_nr_socks is changed from atomic_t to atomic_long_t, while not strictly needed to address Robin problem. Before patch (on a 64bit kernel) : # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max -18446744071562067968 After patch: # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max 2147483648 # cat /proc/sys/fs/file-nr 704 0 2147483648 Reported-by: Robin Holt <holt@sgi.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: David Miller <davem@davemloft.net> Reviewed-by: Robin Holt <holt@sgi.com> Tested-by: Robin Holt <holt@sgi.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
6416ccb7 |
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17-Aug-2010 |
Nick Piggin <npiggin@kernel.dk> |
fs: scale files_lock fs: scale files_lock Improve scalability of files_lock by adding per-cpu, per-sb files lists, protected with an lglock. The lglock provides fast access to the per-cpu lists to add and remove files. It also provides a snapshot of all the per-cpu lists (although this is very slow). One difficulty with this approach is that a file can be removed from the list by another CPU. We must track which per-cpu list the file is on with a new variale in the file struct (packed into a hole on 64-bit archs). Scalability could suffer if files are frequently removed from different cpu's list. However loads with frequent removal of files imply short interval between adding and removing the files, and the scheduler attempts to avoid moving processes too far away. Also, even in the case of cross-CPU removal, the hardware has much more opportunity to parallelise cacheline transfers with N cachelines than with 1. A worst-case test of 1 CPU allocating files subsequently being freed by N CPUs degenerates to contending on a single lock, which is no worse than before. When more than one CPU are allocating files, even if they are always freed by different CPUs, there will be more parallelism than the single-lock case. Testing results: On a 2 socket, 8 core opteron, I measure the number of times the lock is taken to remove the file, the number of times it is removed by the same CPU that added it, and the number of times it is removed by the same node that added it. Booting: locks= 25049 cpu-hits= 23174 (92.5%) node-hits= 23945 (95.6%) kbuild -j16 locks=2281913 cpu-hits=2208126 (96.8%) node-hits=2252674 (98.7%) dbench 64 locks=4306582 cpu-hits=4287247 (99.6%) node-hits=4299527 (99.8%) So a file is removed from the same CPU it was added by over 90% of the time. It remains within the same node 95% of the time. Tim Chen ran some numbers for a 64 thread Nehalem system performing a compile. throughput 2.6.34-rc2 24.5 +patch 24.9 us sys idle IO wait (in %) 2.6.34-rc2 51.25 28.25 17.25 3.25 +patch 53.75 18.5 19 8.75 So significantly less CPU time spent in kernel code, higher idle time and slightly higher throughput. Single threaded performance difference was within the noise of microbenchmarks. That is not to say penalty does not exist, the code is larger and more memory accesses required so it will be slightly slower. Cc: linux-kernel@vger.kernel.org Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
ee2ffa0d |
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17-Aug-2010 |
Nick Piggin <npiggin@kernel.dk> |
fs: cleanup files_lock locking fs: cleanup files_lock locking Lock tty_files with a new spinlock, tty_files_lock; provide helpers to manipulate the per-sb files list; unexport the files_lock spinlock. Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
2069601b |
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12-Aug-2010 |
Linus Torvalds <torvalds@linux-foundation.org> |
Revert "fsnotify: store struct file not struct path" This reverts commit 3bcf3860a4ff9bbc522820b4b765e65e4deceb3e (and the accompanying commit c1e5c954020e "vfs/fsnotify: fsnotify_close can delay the final work in fput" that was a horribly ugly hack to make it work at all). The 'struct file' approach not only causes that disgusting hack, it somehow breaks pulseaudio, probably due to some other subtlety with f_count handling. Fix up various conflicts due to later fsnotify work. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
58939473 |
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10-Aug-2010 |
Tony Battersby <tonyb@cybernetics.com> |
vfs: improve comment describing fget_light() Improve the description of fget_light(), which is currently incorrect about needing a prior refcnt (judging by the way it is actually used). Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
c1e5c954 |
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28-Jul-2010 |
Eric Paris <eparis@redhat.com> |
vfs/fsnotify: fsnotify_close can delay the final work in fput fanotify almost works like so: user context calls fsnotify_* function with a struct file. fsnotify takes a reference on the struct path user context goes about it's buissiness at some later point in time the fsnotify listener gets the struct path fanotify listener calls dentry_open() to create a file which userspace can deal with listener drops the reference on the struct path at some later point the listener calls close() on it's new file With the switch from struct path to struct file this presents a problem for fput() and fsnotify_close(). fsnotify_close() is called when the filp has already reached 0 and __fput() wants to do it's cleanup. The solution presented here is a bit odd. If an event is created from a struct file we take a reference on the file. We check however if the f_count was already 0 and if so we take an EXTRA reference EVEN THOUGH IT WAS ZERO. In __fput() (where we know the f_count hit 0 once) we check if the f_count is non-zero and if so we drop that 'extra' ref and return without destroying the file. Signed-off-by: Eric Paris <eparis@redhat.com>
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#
d7065da0 |
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26-May-2010 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of the magic around f_count in aio __aio_put_req() plays sick games with file refcount. What it wants is fput() from atomic context; it's almost always done with f_count > 1, so they only have to deal with delayed work in rare cases when their reference happens to be the last one. Current code decrements f_count and if it hasn't hit 0, everything is fine. Otherwise it keeps a pointer to struct file (with zero f_count!) around and has delayed work do __fput() on it. Better way to do it: use atomic_long_add_unless( , -1, 1) instead of !atomic_long_dec_and_test(). IOW, decrement it only if it's not the last reference, leave refcount alone if it was. And use normal fput() in delayed work. I've made that atomic_long_add_unless call a new helper - fput_atomic(). Drops a reference to file if it's safe to do in atomic (i.e. if that's not the last one), tells if it had been able to do that. aio.c converted to it, __fput() use is gone. req->ki_file *always* contributes to refcount now. And __fput() became static. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
42e49608 |
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05-Mar-2010 |
Wu Fengguang <fengguang.wu@intel.com> |
vfs: take f_lock on modifying f_mode after open time We'll introduce FMODE_RANDOM which will be runtime modified. So protect all runtime modification to f_mode with f_lock to avoid races. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@kernel.org> [2.6.33.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
89068c57 |
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07-Feb-2010 |
Al Viro <viro@zeniv.linux.org.uk> |
Take ima_file_free() to proper place. Hooks: Just Say No. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
385e3ed4 |
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16-Dec-2009 |
Roland Dreier <rdreier@cisco.com> |
alloc_file(): simplify handling of mnt_clone_write() errors When alloc_file() and init_file() were combined, the error handling of mnt_clone_write() was taken into alloc_file() in a somewhat obfuscated way. Since we don't use the error code for anything except warning, we might as well warn directly without an extra variable. Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
73efc468 |
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16-Dec-2009 |
Roland Dreier <rdreier@cisco.com> |
re-export alloc_file() Commit 3d1e4631 ("get rid of init_file()") removed the export of alloc_file() -- possibly inadvertently, since that commit mainly consisted of deleting the lines between the end of alloc_file() and the start of the code in init_file(). There is in fact one modular use of alloc_file() in the tree, in drivers/infiniband/core/uverbs_main.c, so re-add the export to fix: ERROR: "alloc_file" [drivers/infiniband/core/ib_uverbs.ko] undefined! when CONFIG_INFINIBAND_USER_ACCESS=m. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
0552f879 |
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16-Dec-2009 |
Al Viro <viro@zeniv.linux.org.uk> |
Untangling ima mess, part 1: alloc_file() There are 2 groups of alloc_file() callers: * ones that are followed by ima_counts_get * ones giving non-regular files So let's pull that ima_counts_get() into alloc_file(); it's a no-op in case of non-regular files. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
e81e3f4d |
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04-Dec-2009 |
Eric Paris <eparis@redhat.com> |
fs: move get_empty_filp() deffinition to internal.h All users outside of fs/ of get_empty_filp() have been removed. This patch moves the definition from the include/ directory to internal.h so no new users crop up and removes the EXPORT_SYMBOL. I'd love to see open intents stop using it too, but that's a problem for another day and a smarter developer! Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
2c48b9c4 |
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08-Aug-2009 |
Al Viro <viro@zeniv.linux.org.uk> |
switch alloc_file() to passing struct path ... and have the caller grab both mnt and dentry; kill leak in infiniband, while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
3d1e4631 |
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08-Aug-2009 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of init_file() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
73274127 |
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05-Aug-2009 |
Al Viro <viro@zeniv.linux.org.uk> |
unexport get_empty_filp() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
6c21a7fb |
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22-Oct-2009 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
LSM: imbed ima calls in the security hooks Based on discussions on LKML and LSM, where there are consecutive security_ and ima_ calls in the vfs layer, move the ima_ calls to the existing security_ hooks. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
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#
8d65af78 |
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23-Sep-2009 |
Alexey Dobriyan <adobriyan@gmail.com> |
sysctl: remove "struct file *" argument of ->proc_handler It's unused. It isn't needed -- read or write flag is already passed and sysctl shouldn't care about the rest. It _was_ used in two places at arch/frv for some reason. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
864d7c4c |
|
26-Apr-2009 |
npiggin@suse.de <npiggin@suse.de> |
fs: move mark_files_ro into file_table.c This function walks the s_files lock, and operates primarily on the files in a superblock, so it better belongs here (eg. see also fs_may_remount_ro). [AV: ... and it shouldn't be static after that move] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
96029c4e |
|
26-Apr-2009 |
npiggin@suse.de <npiggin@suse.de> |
fs: introduce mnt_clone_write This patch speeds up lmbench lat_mmap test by about another 2% after the first patch. Before: avg = 462.286 std = 5.46106 After: avg = 453.12 std = 9.58257 (50 runs of each, stddev gives a reasonable confidence) It does this by introducing mnt_clone_write, which avoids some heavyweight operations of mnt_want_write if called on a vfsmount which we know already has a write count; and mnt_want_write_file, which can call mnt_clone_write if the file is open for write. After these two patches, mnt_want_write and mnt_drop_write go from 7% on the profile down to 1.3% (including mnt_clone_write). [AV: mnt_want_write_file() should take file alone and derive mnt from it; not only all callers have that form, but that's the only mnt about which we know that it's already held for write if file is opened for write] Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
a4e49cb6 |
|
08-Mar-2009 |
Tero Roponen <tero.roponen@gmail.com> |
trivial: remove unused variable 'path' in alloc_file() 'struct path' is not used in alloc_file(). Signed-off-by: Tero Roponen <tero.roponen@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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#
68499914 |
|
06-Feb-2009 |
Jonathan Corbet <corbet@lwn.net> |
Rename struct file->f_ep_lock This lock moves out of the CONFIG_EPOLL ifdef and becomes f_lock. For now, epoll remains the only user, but a future patch will use it to protect f_flags as well. Cc: Davide Libenzi <davidel@xmailserver.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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#
6146f0d5 |
|
04-Feb-2009 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
integrity: IMA hooks This patch replaces the generic integrity hooks, for which IMA registered itself, with IMA integrity hooks in the appropriate places directly in the fs directory. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
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#
b6b3fdea |
|
10-Dec-2008 |
Eric Dumazet <dada1@cosmosbay.com> |
filp_cachep can be static in fs/file_table.c Instead of creating the "filp" kmem_cache in vfs_caches_init(), we can do it a litle be later in files_init(), so that filp_cachep is static to fs/file_table.c Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
d76b0d9b |
|
13-Nov-2008 |
David Howells <dhowells@redhat.com> |
CRED: Use creds in file structs Attach creds to file structs and discard f_uid/f_gid. file_operations::open() methods (such as hppfs_open()) should use file->f_cred rather than current_cred(). At the moment file->f_cred will be current_cred() at this point. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Signed-off-by: James Morris <jmorris@namei.org>
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#
86a264ab |
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13-Nov-2008 |
David Howells <dhowells@redhat.com> |
CRED: Wrap current->cred and a few other accessors Wrap current->cred and a few other accessors to hide their actual implementation. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
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#
b6dff3ec |
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13-Nov-2008 |
David Howells <dhowells@redhat.com> |
CRED: Separate task security context from task_struct Separate the task security context from task_struct. At this point, the security data is temporarily embedded in the task_struct with two pointers pointing to it. Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in entry.S via asm-offsets. With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
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#
233e70f4 |
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31-Oct-2008 |
Al Viro <viro@ZenIV.linux.org.uk> |
saner FASYNC handling on file close As it is, all instances of ->release() for files that have ->fasync() need to remember to evict file from fasync lists; forgetting that creates a hole and we actually have a bunch that *does* forget. So let's keep our lives simple - let __fput() check FASYNC in file->f_flags and call ->fasync() there if it's been set. And lose that crap in ->release() instances - leaving it there is still valid, but we don't have to bother anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
aeb5d727 |
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02-Sep-2008 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH] introduce fmode_t, do annotations Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
516e0cc5 |
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25-Jul-2008 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH] f_count may wrap around make it atomic_long_t; while we are at it, get rid of useless checks in affs, hfs and hpfs - ->open() always has it equal to 1, ->release() - to 0. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
9f3acc31 |
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24-Apr-2008 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH] split linux/file.h Initial splitoff of the low-level stuff; taken to fdtable.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
ad775f5a |
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15-Feb-2008 |
Dave Hansen <haveblue@us.ibm.com> |
[PATCH] r/o bind mounts: debugging for missed calls There have been a few oopses caused by 'struct file's with NULL f_vfsmnts. There was also a set of potentially missed mnt_want_write()s from dentry_open() calls. This patch provides a very simple debugging framework to catch these kinds of bugs. It will WARN_ON() them, but should stop us from having any oopses or mnt_writer count imbalances. I'm quite convinced that this is a good thing because it found bugs in the stuff I was working on as soon as I wrote it. [hch: made it conditional on a debug option. But it's still a little bit too ugly] [hch: merged forced remount r/o fix from Dave and akpm's fix for the fix] Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
4a3fd211 |
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15-Feb-2008 |
Dave Hansen <haveblue@us.ibm.com> |
[PATCH] r/o bind mounts: elevate write count for open()s This is the first really tricky patch in the series. It elevates the writer count on a mount each time a non-special file is opened for write. We used to do this in may_open(), but Miklos pointed out that __dentry_open() is used as well to create filps. This will cover even those cases, while a call in may_open() would not have. There is also an elevated count around the vfs_create() call in open_namei(). See the comments for more details, but we need this to fix a 'create, remount, fail r/w open()' race. Some filesystems forego the use of normal vfs calls to create struct files. Make sure that these users elevate the mnt writer count because they will get __fput(), and we need to make sure they're balanced. Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
aceaf78d |
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15-Feb-2008 |
Dave Hansen <haveblue@us.ibm.com> |
[PATCH] r/o bind mounts: create helper to drop file write access If someone decides to demote a file from r/w to just r/o, they can use this same code as __fput(). NFS does just that, and will use this in the next patch. AV: drop write access in __fput() only after we evict from file list. Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Cc: Erez Zadok <ezk@cs.sunysb.edu> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J Bruce Fields" <bfields@fieldses.org> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
430e285e |
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15-Feb-2008 |
Dave Hansen <haveblue@us.ibm.com> |
[PATCH] fix up new filp allocators Some new uses of get_empty_filp() have crept in; switched to alloc_file() to make sure that pieces of initialization won't be missing. We really need to kill get_empty_filp(). [AV] fixed dentry leak on failure exit in anon_inode_getfd() Cc: Erez Zadok <ezk@cs.sunysb.edu> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J Bruce Fields" <bfields@fieldses.org> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
fc9b52cd |
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08-Feb-2008 |
Harvey Harrison <harvey.harrison@gmail.com> |
fs: remove fastcall, it is always empty [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
cfdaf9e5 |
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19-Oct-2007 |
Matthias Kaehlcke <matthias.kaehlcke@gmail.com> |
fs/file_table.c: use list_for_each_entry() instead of list_for_each() fs/file_table.c: use list_for_each_entry() instead of list_for_each() in fs_may_remount_ro() Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
ce8d2cdf |
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17-Oct-2007 |
Dave Hansen <haveblue@us.ibm.com> |
r/o bind mounts: filesystem helpers for custom 'struct file's Why do we need r/o bind mounts? This feature allows a read-only view into a read-write filesystem. In the process of doing that, it also provides infrastructure for keeping track of the number of writers to any given mount. This has a number of uses. It allows chroots to have parts of filesystems writable. It will be useful for containers in the future because users may have root inside a container, but should not be allowed to write to somefilesystems. This also replaces patches that vserver has had out of the tree for several years. It allows security enhancement by making sure that parts of your filesystem read-only (such as when you don't trust your FTP server), when you don't want to have entire new filesystems mounted, or when you want atime selectively updated. I've been using the following script to test that the feature is working as desired. It takes a directory and makes a regular bind and a r/o bind mount of it. It then performs some normal filesystem operations on the three directories, including ones that are expected to fail, like creating a file on the r/o mount. This patch: Some filesystems forego the vfs and may_open() and create their own 'struct file's. This patch creates a couple of helper functions which can be used by these filesystems, and will provide a unified place which the r/o bind mount code may patch. Also, rename an existing, static-scope init_file() to a less generic name. Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
4975e45f |
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17-Oct-2007 |
Denis Cheng <crquan@gmail.com> |
fs: use kmem_cache_zalloc instead Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
52d9f3b4 |
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17-Oct-2007 |
Peter Zijlstra <a.p.zijlstra@chello.nl> |
lib: percpu_counter_sum_positive s/percpu_counter_sum/&_positive/ Because its consitent with percpu_counter_read* Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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e63340ae |
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08-May-2007 |
Randy Dunlap <randy.dunlap@oracle.com> |
header cleaning: don't include smp_lock.h when not used Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
0f7fc9e4 |
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08-Dec-2006 |
Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> |
[PATCH] VFS: change struct file to use struct path This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
609d7fa9 |
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02-Oct-2006 |
Eric W. Biederman <ebiederm@xmission.com> |
[PATCH] file: modify struct fown_struct to use a struct pid File handles can be requested to send sigio and sigurg to processes. By tracking the destination processes using struct pid instead of pid_t we make the interface safe from all potential pid wrap around problems. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
577c4eb0 |
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27-Sep-2006 |
Theodore Ts'o <tytso@mit.edu> |
[PATCH] inode-diet: Move i_cdev into a union Move the i_cdev pointer in struct inode into a union. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
6ab3d562 |
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30-Jun-2006 |
Jörn Engel <joern@wohnheim.fh-wedel.de> |
Remove obsolete #include <linux/config.h> Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
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#
0216bfcf |
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23-Jun-2006 |
Mingming Cao <cmm@us.ibm.com> |
[PATCH] percpu counter data type changes to suppport more than 2**31 ext3 free blocks counter The percpu counter data type are changed in this set of patches to support more users like ext3 who need more than 32 bit to store the free blocks total in the filesystem. - Generic perpcu counters data type changes. The size of the global counter and local counter were explictly specified using s64 and s32. The global counter is changed from long to s64, while the local counter is changed from long to s32, so we could avoid doing 64 bit update in most cases. - Users of the percpu counters are updated to make use of the new percpu_counter_init() routine now taking an additional parameter to allow users to pass the initial value of the global counter. Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
5a6b7951 |
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23-Mar-2006 |
Benjamin LaHaise <bcrl@linux.intel.com> |
[PATCH] get_empty_filp tweaks, inline epoll_init_file() Eliminate a handful of cache references by keeping current in a register instead of reloading (helps x86) and avoiding the overhead of a function call. Inlining eventpoll_init_file() saves 24 bytes. Also reorder file initialization to make writes occur more sequentially. Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
529bf6be |
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07-Mar-2006 |
Dipankar Sarma <dipankar@in.ibm.com> |
[PATCH] fix file counting I have benchmarked this on an x86_64 NUMA system and see no significant performance difference on kernbench. Tested on both x86_64 and powerpc. The way we do file struct accounting is not very suitable for batched freeing. For scalability reasons, file accounting was constructor/destructor based. This meant that nr_files was decremented only when the object was removed from the slab cache. This is susceptible to slab fragmentation. With RCU based file structure, consequent batched freeing and a test program like Serge's, we just speed this up and end up with a very fragmented slab - llm22:~ # cat /proc/sys/fs/file-nr 587730 0 758844 At the same time, I see only a 2000+ objects in filp cache. The following patch I fixes this problem. This patch changes the file counting by removing the filp_count_lock. Instead we use a separate percpu counter, nr_files, for now and all accesses to it are through get_nr_files() api. In the sysctl handler for nr_files, we populate files_stat.nr_files before returning to user. Counting files as an when they are created and destroyed (as opposed to inside slab) allows us to correctly count open files with RCU. Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
16f7e0fe |
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11-Jan-2006 |
Randy Dunlap <rdunlap@infradead.org> |
[PATCH] capable/capability.h (fs/) fs: Use <linux/capability.h> where capable() is used. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
095975da |
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08-Jan-2006 |
Nick Piggin <nickpiggin@yahoo.com.au> |
[PATCH] rcu file: use atomic primitives Use atomic_inc_not_zero for rcu files instead of special case rcuref. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
2109a2d1 |
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07-Nov-2005 |
Pekka J Enberg <penberg@cs.Helsinki.FI> |
[PATCH] mm: rename kmem_cache_s to kmem_cache This patch renames struct kmem_cache_s to kmem_cache so we can start using it instead of kmem_cache_t typedef. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
2f512016 |
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30-Oct-2005 |
Eric Dumazet <dada1@cosmosbay.com> |
[PATCH] reduce sizeof(struct file) Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead in a memory location that is not anymore used at call_rcu(&f->f_rcuhead, file_free_rcu) time, to reduce the size of this critical kernel object. The trick I used is to move f_rcuhead and f_list in an union called f_u The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list becomes f_u.f_list Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
ab2af1f5 |
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09-Sep-2005 |
Dipankar Sarma <dipankar@in.ibm.com> |
[PATCH] files: files struct with RCU Patch to eliminate struct files_struct.file_lock spinlock on the reader side and use rcu refcounting rcuref_xxx api for the f_count refcounter. The updates to the fdtable are done by allocating a new fdtable structure and setting files->fdt to point to the new structure. The fdtable structure is protected by RCU thereby allowing lock-free lookup. For fd arrays/sets that are vmalloced, we use keventd to free them since RCU callbacks can't sleep. A global list of fdtable to be freed is not scalable, so we use a per-cpu list. If keventd is already handling the current cpu's work, we use a timer to defer queueing of that work. Since the last publication, this patch has been re-written to avoid using explicit memory barriers and use rcu_assign_pointer(), rcu_dereference() premitives instead. This required that the fd information is kept in a separate structure (fdtable) and updated atomically. Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
2832e936 |
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06-Sep-2005 |
Eric Dumazet <dada1@cosmosbay.com> |
[PATCH] remove file.f_maxcount struct file cleanup: f_maxcount has an unique value (INT_MAX). Just use the hard-wired value. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
0eeca283 |
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12-Jul-2005 |
Robert Love <rml@novell.com> |
[PATCH] inotify inotify is intended to correct the deficiencies of dnotify, particularly its inability to scale and its terrible user interface: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a system call that returns a fd, not SIGIO. You get a single fd, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. Inotify is currently used by Beagle (a desktop search infrastructure), Gamin (a FAM replacement), and other projects. See Documentation/filesystems/inotify.txt. Signed-off-by: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
af4d2ecb |
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23-Jun-2005 |
Kirill Korotaev <dev@sw.ru> |
[PATCH] Fix of bogus file max limit messages This patch fixes incorrect and bogus kernel messages that file-max limit reached when the allocation fails Signed-Off-By: Kirill Korotaev <dev@sw.ru> Signed-Off-By: Denis Lunev <den@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
1da177e4 |
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16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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