Adjust all struct dirent creations (again), this time to use offsetof().

The dirent struct is not packed, so offsetof(dirent, d_name) != sizeof(dirent).
Thus in order not to waste the alignment bytes (which are significant,
on x86_64 at least, sizeof(dirent)==32, but offsetof(...)=26.)

This is also the most portable way to handle things, and should
work just fine in cross-platform code that has a non-zero-sized d_name.

write_overlay: readlink behavior change

Change-Id: I036f3e7f84e4a771846482fe81c2db4c4d718aef
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2754
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

write_overlay: Fix SMAP violation in OverlayInode::Read

Change-Id: I66d852008a4375bb9295bc0238ed6289fb8439d5
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2046
Reviewed-by: Jérôme Duval <jerome.duval@gmail.com>

write_overlay: Read()/Write() with user_memcpy().

NodeMonitor: Added B_WATCH_CHILDREN flag.

* Added a directory argument for notify_{stat/attribute}_changed().
* This allows to watch only a directory, and get the notifications for
all of its files, not just add/remove entry notifications.

add-ons/kernel: add spaces between literals and identifiers

Due to introduction of user-defined suffixes C++11 requires that there
is a space between literal and identifier to avoid ambiguity.

This patch makes the whole kernel build successfully with C++11.

write_overlay: fixed three warnings, I hope correctly.

* warnings about comparison between signed and unsigned integer expressions.

64-bit compilation fixes for write_overlay and intel partitioning system modules.

added a file system call preallocate() as described in #6285, currently unused


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39006 a95241bf-73f2-0310-859d-f6bbb57e9c96

Changed the type of the "op" parameter of the fs_vnode_ops::ioctl() hook and
the _kern_ioctl() syscall from ulong to uint32.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36927 a95241bf-73f2-0310-859d-f6bbb57e9c96

The vnode->private_node holds our object, not vnode itself.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35191 a95241bf-73f2-0310-859d-f6bbb57e9c96

Also return B_NOT_A_DIRECTORY in write_overlay when appropriate.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33035 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement attribute support in write_overlay. It mostly uses the same backends
as the other node operations.
* Differentiate between data and metadata modification, so that changes to
attributes or stat fields (other than size) dont't prevent direct IO relay.
* Suppress child finish notifications when sending subrequests to the
underlaying filesystem. Otherwise the request can be gone by the time we
try to complete it.
* Fix offsets used for IORequest::CopyData().
* Some refactoring.
* Added locking.

With that a write_overlay can be put on attribute enabled filesystems to either
make them writeable or snapshot them. This allows for example for a working
BFS based LiveCD.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32937 a95241bf-73f2-0310-859d-f6bbb57e9c96

We need to notify the request also in the error case.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32915 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement the rest of the IO hook. We now do directly satisfy write requests
by writing them into our buffers and directly satisfy read requests by copying
our buffers, filling any gaps by spawning off subrequests to the underlaying
filesystem.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32900 a95241bf-73f2-0310-859d-f6bbb57e9c96

Enable the IO hook for both attribute and write overlay. Attribute overlay isn't
concerned by it as it does not do file data, it simply passes the hook through.
In the write_overlay case we check for write operations and for modified nodes.
In both cases we return B_NOT_SUPPORTED which will cause a fallback to
synchronous IO. The main problem with the fallback is not that it is synchronous
but that the physical buffers of the request will be mapped and filled page
wise, which makes it slow for various reasons. In any case with this setup all
reads to write_overlay that can go through unmodified now do. This should speed
up CD boot as there is no physical to virtual translation overhead and no limit
to page wise reads. In the best case it should now read 256 blocks at the time
instead of always falling back to 2. My tests show no side effects on creating,
writing or partially modifying nodes so far.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32897 a95241bf-73f2-0310-859d-f6bbb57e9c96

When we truncate or resize the file we need to trim the write_buffers. Otherwise
we waste space, but we also incorrectly fail to update the size for all writes
that do not go beyond the previous file size.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32825 a95241bf-73f2-0310-859d-f6bbb57e9c96

Take into account that we may look up "." or ".." and we must obviously not set
the parent directory in those cases. Also, when updating the parent directory
we need to update the ".." dirent if we already populated it with a different
value before.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32823 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement TODO: Check for non-empty directories before removing an entry. This
fixes #4358, there changing the Tracker preferences causes some default
directories to be created, like "home" and "config", which were previously
simply killing off the real ones.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32822 a95241bf-73f2-0310-859d-f6bbb57e9c96

If we create new nodes or modify existing ones, especially directories, we must
ensure that these nodes are never put. As they keep all changes in memory,
putting them and consequently freeing them destroys the modifications without
a way to get them back from the underlaying filesystem. In case a created node
was put but still had its entry in the parent directory this could also lead
to the situation where an invalid node was requested from the underlaying
filesystem, leading to #4347.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32815 a95241bf-73f2-0310-859d-f6bbb57e9c96

Removed just a bit too much in r30927.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30932 a95241bf-73f2-0310-859d-f6bbb57e9c96

We need to update the name and parent directory when renaming/moving.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30930 a95241bf-73f2-0310-859d-f6bbb57e9c96

* When removing entries properly call remove_vnode().
* Move notifications around so they are sent at the right time.
* Use notify_entry_moved() instead of generating a removal and creation
notification.
* Allow replacing entries.
* Added a TODO regarding non-empty directories.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30929 a95241bf-73f2-0310-859d-f6bbb57e9c96

Make reading the write_overlay more efficient. Instead of always reading the
original file and then overwriting it with what we have in memory, just linearly
fill the buffer, closing gaps between our buffers with original file content as
needed.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30927 a95241bf-73f2-0310-859d-f6bbb57e9c96

Only use read_pages() when we need to. Otherwise we bypass the cache of the
upper layer, degrading performance qutie a bit.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30925 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement read/write_pages using Read()/Write(), io will follow later.
* Create a file cache for created overlay nodes. It is unused and disabled, but
causes a vnode cache to be created. This is required for mapping a file, which
in turn is required for executables to be loaded. With that copied or newly
created executables should work on top of write_overlay. Will think about and
implement a more direct way of getting that cache later today.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30910 a95241bf-73f2-0310-859d-f6bbb57e9c96

Write can be called without cookie (in the CreateSymlink() case for example).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30907 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement O_APPEND.
* Also make set_flags available for setting it. O_NONBLOCK is ignored as in BFS.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30903 a95241bf-73f2-0310-859d-f6bbb57e9c96

Apply r30890, adding a missing put_vnode() on error, to write_overlay as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30899 a95241bf-73f2-0310-859d-f6bbb57e9c96

Move the B_UNSUPPORTED return into the macro. No functional change.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30897 a95241bf-73f2-0310-859d-f6bbb57e9c96

We don't want to use the OVERLAY_CALL macro for can_page() as it returns a bool
and not a status_t. In case of virtual files it would have wrongly returned
B_UNSUPPORTED, resulting in true instead of false.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30895 a95241bf-73f2-0310-859d-f6bbb57e9c96

Fix leaking the old entry name when renaming actually succeeds.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30891 a95241bf-73f2-0310-859d-f6bbb57e9c96

Removed the fs_vnode_ops::create_dir() parameter for returning the ID of the
newly created dir. The VFS really doesn't need it and for some file systems
it might not be easy to get by. Several file systems (e.g. rootfs and fat)
were ignoring the parameter anyway.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29719 a95241bf-73f2-0310-859d-f6bbb57e9c96

Ensure that our stat buffer is available when opening. Otherwise reads could
fail and the O_TRUNC might be overwritten as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29520 a95241bf-73f2-0310-859d-f6bbb57e9c96

* This should mostly complete the write_overlay.
* Fix memory leaks here and there.
* Virtualize the dirent list.
* Handle "." and ".." ourselfs as at least iso9660 cannot really know them in
the readdir call and therefore returns different values than on lookup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29458 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implemented create/create dir/create symlink and remove/remove dir in the
write_overlay and add the necessary infrastructure for it.
* Fix setting permissions through write stat.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29268 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implemented write stat.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29260 a95241bf-73f2-0310-859d-f6bbb57e9c96

Rename the trace output as well.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29256 a95241bf-73f2-0310-859d-f6bbb57e9c96

Split overlay filesystem into attribute_overlay and write_overlay.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29255 a95241bf-73f2-0310-859d-f6bbb57e9c96

Preparing to split the overlay filesystem into an attribute_overlay and write_overlay module.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29253 a95241bf-73f2-0310-859d-f6bbb57e9c96

add-ons/kernel: add spaces between literals and identifiers

Due to introduction of user-defined suffixes C++11 requires that there
is a space between literal and identifier to avoid ambiguity.

This patch makes the whole kernel build successfully with C++11.

write_overlay: fixed three warnings, I hope correctly.

* warnings about comparison between signed and unsigned integer expressions.

64-bit compilation fixes for write_overlay and intel partitioning system modules.

added a file system call preallocate() as described in #6285, currently unused


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39006 a95241bf-73f2-0310-859d-f6bbb57e9c96

Changed the type of the "op" parameter of the fs_vnode_ops::ioctl() hook and
the _kern_ioctl() syscall from ulong to uint32.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36927 a95241bf-73f2-0310-859d-f6bbb57e9c96

The vnode->private_node holds our object, not vnode itself.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35191 a95241bf-73f2-0310-859d-f6bbb57e9c96

Also return B_NOT_A_DIRECTORY in write_overlay when appropriate.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33035 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement attribute support in write_overlay. It mostly uses the same backends
as the other node operations.
* Differentiate between data and metadata modification, so that changes to
attributes or stat fields (other than size) dont't prevent direct IO relay.
* Suppress child finish notifications when sending subrequests to the
underlaying filesystem. Otherwise the request can be gone by the time we
try to complete it.
* Fix offsets used for IORequest::CopyData().
* Some refactoring.
* Added locking.

With that a write_overlay can be put on attribute enabled filesystems to either
make them writeable or snapshot them. This allows for example for a working
BFS based LiveCD.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32937 a95241bf-73f2-0310-859d-f6bbb57e9c96

We need to notify the request also in the error case.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32915 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement the rest of the IO hook. We now do directly satisfy write requests
by writing them into our buffers and directly satisfy read requests by copying
our buffers, filling any gaps by spawning off subrequests to the underlaying
filesystem.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32900 a95241bf-73f2-0310-859d-f6bbb57e9c96

Enable the IO hook for both attribute and write overlay. Attribute overlay isn't
concerned by it as it does not do file data, it simply passes the hook through.
In the write_overlay case we check for write operations and for modified nodes.
In both cases we return B_NOT_SUPPORTED which will cause a fallback to
synchronous IO. The main problem with the fallback is not that it is synchronous
but that the physical buffers of the request will be mapped and filled page
wise, which makes it slow for various reasons. In any case with this setup all
reads to write_overlay that can go through unmodified now do. This should speed
up CD boot as there is no physical to virtual translation overhead and no limit
to page wise reads. In the best case it should now read 256 blocks at the time
instead of always falling back to 2. My tests show no side effects on creating,
writing or partially modifying nodes so far.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32897 a95241bf-73f2-0310-859d-f6bbb57e9c96

When we truncate or resize the file we need to trim the write_buffers. Otherwise
we waste space, but we also incorrectly fail to update the size for all writes
that do not go beyond the previous file size.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32825 a95241bf-73f2-0310-859d-f6bbb57e9c96

Take into account that we may look up "." or ".." and we must obviously not set
the parent directory in those cases. Also, when updating the parent directory
we need to update the ".." dirent if we already populated it with a different
value before.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32823 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implement TODO: Check for non-empty directories before removing an entry. This
fixes #4358, there changing the Tracker preferences causes some default
directories to be created, like "home" and "config", which were previously
simply killing off the real ones.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32822 a95241bf-73f2-0310-859d-f6bbb57e9c96

If we create new nodes or modify existing ones, especially directories, we must
ensure that these nodes are never put. As they keep all changes in memory,
putting them and consequently freeing them destroys the modifications without
a way to get them back from the underlaying filesystem. In case a created node
was put but still had its entry in the parent directory this could also lead
to the situation where an invalid node was requested from the underlaying
filesystem, leading to #4347.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32815 a95241bf-73f2-0310-859d-f6bbb57e9c96

Removed just a bit too much in r30927.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30932 a95241bf-73f2-0310-859d-f6bbb57e9c96

We need to update the name and parent directory when renaming/moving.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30930 a95241bf-73f2-0310-859d-f6bbb57e9c96

* When removing entries properly call remove_vnode().
* Move notifications around so they are sent at the right time.
* Use notify_entry_moved() instead of generating a removal and creation
notification.
* Allow replacing entries.
* Added a TODO regarding non-empty directories.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30929 a95241bf-73f2-0310-859d-f6bbb57e9c96

Make reading the write_overlay more efficient. Instead of always reading the
original file and then overwriting it with what we have in memory, just linearly
fill the buffer, closing gaps between our buffers with original file content as
needed.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30927 a95241bf-73f2-0310-859d-f6bbb57e9c96

Only use read_pages() when we need to. Otherwise we bypass the cache of the
upper layer, degrading performance qutie a bit.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30925 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement read/write_pages using Read()/Write(), io will follow later.
* Create a file cache for created overlay nodes. It is unused and disabled, but
causes a vnode cache to be created. This is required for mapping a file, which
in turn is required for executables to be loaded. With that copied or newly
created executables should work on top of write_overlay. Will think about and
implement a more direct way of getting that cache later today.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30910 a95241bf-73f2-0310-859d-f6bbb57e9c96

Write can be called without cookie (in the CreateSymlink() case for example).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30907 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implement O_APPEND.
* Also make set_flags available for setting it. O_NONBLOCK is ignored as in BFS.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30903 a95241bf-73f2-0310-859d-f6bbb57e9c96

Apply r30890, adding a missing put_vnode() on error, to write_overlay as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30899 a95241bf-73f2-0310-859d-f6bbb57e9c96

Move the B_UNSUPPORTED return into the macro. No functional change.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30897 a95241bf-73f2-0310-859d-f6bbb57e9c96

We don't want to use the OVERLAY_CALL macro for can_page() as it returns a bool
and not a status_t. In case of virtual files it would have wrongly returned
B_UNSUPPORTED, resulting in true instead of false.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30895 a95241bf-73f2-0310-859d-f6bbb57e9c96

Fix leaking the old entry name when renaming actually succeeds.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30891 a95241bf-73f2-0310-859d-f6bbb57e9c96

Removed the fs_vnode_ops::create_dir() parameter for returning the ID of the
newly created dir. The VFS really doesn't need it and for some file systems
it might not be easy to get by. Several file systems (e.g. rootfs and fat)
were ignoring the parameter anyway.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29719 a95241bf-73f2-0310-859d-f6bbb57e9c96

Ensure that our stat buffer is available when opening. Otherwise reads could
fail and the O_TRUNC might be overwritten as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29520 a95241bf-73f2-0310-859d-f6bbb57e9c96

* This should mostly complete the write_overlay.
* Fix memory leaks here and there.
* Virtualize the dirent list.
* Handle "." and ".." ourselfs as at least iso9660 cannot really know them in
the readdir call and therefore returns different values than on lookup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29458 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implemented create/create dir/create symlink and remove/remove dir in the
write_overlay and add the necessary infrastructure for it.
* Fix setting permissions through write stat.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29268 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implemented write stat.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29260 a95241bf-73f2-0310-859d-f6bbb57e9c96

Rename the trace output as well.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29256 a95241bf-73f2-0310-859d-f6bbb57e9c96

Split overlay filesystem into attribute_overlay and write_overlay.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29255 a95241bf-73f2-0310-859d-f6bbb57e9c96

Preparing to split the overlay filesystem into an attribute_overlay and write_overlay module.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29253 a95241bf-73f2-0310-859d-f6bbb57e9c96