Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r256724:

Make geom_label(4) resize-aware. This fixes a situation when "gpart resize"
would resize a partition, but label providers - e.g. /dev/gptid/XXX - would
stay the same size.

MFC r256766:

Fix build with gcc by spelling unused format string as "unused" instead of NULL.

Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

- Use int8_t type for the mftrecsz field in g_label_ntfs. char type
used previously caused probe failure on platforms where char is unsigned
(e.g. ARM), as mftrecsz can be negative.

Submitted by: Ilya Bakulin <ilya@bakulin.de>
MFC after: 2 weeks

Comment typo fix.

Is aware of the importance of comments: dim

Fix the buffer-overflow-fixing fixes.

Pointy-hat to: me, for not realizing snprintf() is available in kernel.
Thanks to: jh, for bringing me the good news of snprintf(), Pawel Worach, for
noting that the panic can be provoked in i386 and not in amd64

Introduce glabel labels based on GEOM ident attributes. In this initial
implementation, error on the side of conservatism and only create labels
for GEOMs of classes DISK and MULTIPATH.

Discussed with: trasz
Approved by: silence from freebsd-geom@

g_label_ntfs_taste: Abort taste is recsize == 0

This will avoid a 0-byte read (in g_read_data()) leading to a panic, if
previously read data are erroneous.

Suggested by: John-Mark Gurney <jmg@funkthat.com>

g_label_ntfs.c: Mark structures as __packed

Without this, read data is mis-interpreted. This could trigger a panic,
as was the case on one computer where computed "recsize" was zero,
leading to a call to g_read_page() asking for 0 bytes.

Remove ntfs headers dependency for g_label_ntfs.c by redefining the
used structs and values.

This patch is not targeted for MFC.

Mangle label names containing spaces, non-printable characters '%' or
'"'. Mangling is only done for label names read from file system
metadata. Encoding resembles URL encoding. For example, the space
character becomes %20.

Help by: kib
Discussed with: imp, kib, pjd

- Don't pass geom and provider names as format strings.
- Add __printflike() attributes.
- Remove an extra argument for the g_new_geomf() call in swapongeom_ev().

Reviewed by: pjd

Fix problem with geom_label(4) not recognizing UFS labels on filesystems
extended using growfs(8). The problem here is that geom_label checks if
the filesystem size recorded in UFS superblock is equal to the provider
(i.e. device) size. This check cannot be removed due to backward
compatibility. On the other hand, in most cases growfs(8) cannot set
fs_size in the superblock to match the provider size, because, differently
from newfs(8), it cannot recompute cylinder group sizes.

To fix this problem, add another superblock field, fs_providersize, used
only for this purpose. The geom_label(4) will attach if either fs_size
(filesystem created with newfs(8)) or fs_providersize (filesystem expanded
using growfs(8)) matches the device size.

PR: kern/165962
Reviewed by: mckusick
Sponsored by: FreeBSD Foundation

It seems that it is preferable to keep support for glabel also for
filesystems that we don't support natively.
Revert part of r241636 to do so.

This patch is not targeted for MFC.

Requested by: gleb, jhb

Disconnect non-MPSAFE NTFS from the build in preparation for dropping
GIANT from VFS. This code is particulary broken and fragile and other
in-kernel implementations around, found in other operating systems,
don't really seem clean and solid enough to be imported at all.
If someone wants to reconsider in-kernel NTFS implementation for
inclusion again, a fair effort for completely fixing and cleaning it
up is expected.

In the while NTFS regular users can use FUSE interface and ntfs-3g
port to work with their NTFS partitions.

This is not targeted for MFC.

Revert r235918 for now and add comment explaining the reason for the
size check.

Make g_label(4) ignore provider size when looking for UFS labels.
Without it, it fails to create labels for filesystems resized by
growfs(8).

PR: kern/165962
Submitted by: Olivier Cochard-Labbe <olivier at cochard dot me>

Include sys/sbuf.h directly.

Reviewed by: pjd

When checking existence of providers skip those which are orphaned.

PR: kern/132273
MFC after: 2 week

Some linux distros put mount point into the ext2fs labels, such as '/', or
'/boot', which confuses the devfs code and can cause userland programs to
fail reading /dev/ext2fs directory with weird error code, such as any
program that uses pwlib.

Strip any leading slashes before feeding the label to the geom_label code.

Sponsored by: Sippy Software, Inc.

MFC after: 1 week

Add some FEATURE macros for various GEOM classes.

No FreeBSD version bump, the userland application to query the features will
be committed last and can serve as an indication of the availablility if
needed.

Sponsored by: Google Summer of Code 2010
Submitted by: kibab
Reviewed by: silence on geom@ during 2 weeks
X-MFC after: to be determined in last commit with code from this project

- Report an error when a label with invalid name is attempted to be
created with glabel(8).
- Fix a typo in an error message.
- Fix comment typos.

Approved by: pjd

g_label: fix possible NULL pointer dereference

in case glabel debug level is >= 1 and gp->provider list is empty
for some reason

Found by: clang static analyzer
MFC after: 4 days

Provide a set of sysctls and tunables to disable device node creation
for specific "kinds" of disk labels - for example, GPT UUIDs. Reason
for this is that sometimes, other GEOM classes attach to these device
nodes instead of the proper ones - e.g. they attach to /dev/gptid/XXX
instead of /dev/ada0p2, which is annoying.

Reviewed by: pjd (earlier version)
MFC after: 1 month

If provider is open for writing when we taste it, skip it for classes that
depend on on-disk metadata. This was we won't attach to providers that are used
by other classes. For example we don't want to configure partitions on da0 if
it is part of gmirror, what we really want is partitions on mirror/foo.

During regular work it works like this: if provider is open for writing a class
receives the spoiled event from GEOM and detaches, once provider is closed the
taste event is send again and class can rediscover its metadata if it is still
there. This doesn't work that way when new class arrives, because GEOM gives
all existing providers for it to taste, also those open for writing. Classes
have to decided on their own if they want to deal with such providers (eg.
geom_dev) or not (classes modified by this commit).

Reported by: des, Oliver Lehmann <lehmann@ans-netz.de>
Tested by: des, Oliver Lehmann <lehmann@ans-netz.de>
Discussed with: phk, marcel
Reviewed by: marcel
MFC after: 3 days

Fix tabs, slightly improve comments.

Approved by: gnn (mentor) (original)
Noticed by: stas

Add support for labels derived from GPT metadata.

Approved by: gnn (mentor)
Reviewed by: pjd
PR: 128398
Submitted by: Marius Nuennerich < marius at nuenneri.ch >

Crank the debug level necessary to display the "Label foo is removed"
and "Label for provider ..." messages up from 0 to 1.

Create GEOM labels from UFS IDs, e.g. /dev/ufsid/49c97b1faa2adc43. UFS IDs
are always present and can be used to identify file systems (useful if
hardware devices move often).

Actually-by: pjd
Approved by: gnn (mentor)

- Use the correct argument when determining the buffer size.

PR: kern/131575
MFC after: 2 days

o s/resiserfs_sb/reiserfs_sb/.

Submitted by: Ighighi

Remove trailing spaces.

Fix detecting of UFS1 label when mediasize%fragsize != 0.

Submitted by: Stanislav Sedov
PR: kern/84637
MFC after: 1 week

Handle MSDOS file systems properly. Before the change file systems
created on Windows XP (and others maybe) were not detected.
We detected only those created with newfs_msdos(8).

Submitted by: Tobias Reifenberger <treif@mayn.de>
style(9)ified by: pjd

Verify if a label doesn't point to the parent directory.

We need to check if file system size is equal to provider's size, because
sysinstall(8) still bogusly puts first partition at offset 0 instead of 16,
so glabel/ufs will find file system on slice instead of partition.

Before sysinstall is fixed, we must keep this code, which means that we
wont't be able to detect UFS file systems created with 'newfs -s ...'.

PS. bsdlabel(8) creates partitions properly.

MFC after: 3 days

Inform when label disappears.

MFC after: 3 days

- Do not depend on fact that file system covers entire provider.
It won't work for file systems created with -s option.
Use better file system verfication.
- Add myself to the copyright.

MFC after: 3 days

This function returns nothing.

If provider's sector size prevents reading SBLOCKSIZE bytes return
immediatelly.

Remove trailing spaces.

Style cleanups.

X-MFC-after: Already MFCed to RELENG_6 by accident.

Don't pass error value pointer to g_read_data(9) at all if we don't
have any use of it.

Suggested by: pjd

Check for g_read_data(9) errors properly:

o The only indication of error condition is NULL value returned by
the function;

o value pointed to by error argument is undefined in the case when
operation completes successfully.

Discussed with: phk

We do nothing with returned error value, so just remove it.

Check value returned by g_read_data(9), otherwise we can end in panic(9)
if read error happens.

MFC after: 1 week

Add checking for File record magic.

Verify length of the data to read as well.

Verify offset before reading.

MFC after: 2 days

Add NTFS labeling function.

Reviewed by:pjd

Verify if we can actually read the data at given offset.

Reported by: Martin <nakal@nurfuerspam.de>

Back-out the change from revision 1.14 and allow for '/' in labels again.

Convinced by: green, Gavin Atkinson, dougb, gordon
MFC after: 1 day

Provide more complete "How to add a new file system to glabel." list.

MFC after: 1 week

Add code for Ext2FS and ReiserFS labels recognition.

Submitted by: Stanislav Sedov <stas@310.ru>
PR: kern/84638
MFC after: 1 week

Avoid creating directories in devfs by changing all '/' in labels to '_'.

Idea from: Stanislav Sedov <stas@310.ru>
MFC after: 3 days

The size of a filesystem may be less than the size of the provider it
resides on. Fix the special case of the filesystem fragment size not
evenly dividing the size of the provider. Fixing the general case
probably requires better superblock validation (left as an exercise to
the reader).

- Add md_provsize field to metadata, which will help with
shared-last-sector problem.
After this change, even if there is more than one provider with the same
last sector, the proper one will be chosen based on its size.
It still doesn't fix the 'c' partition problem (when da0s1 can be confused
with da0s1c) and situation when 'a' partition starts at offset 0
(then da0s1a can be confused with da0s1 and da0s1c). One can use '-h'
option there, when creating device or avoid sharing last sector.
Actually, when providers share the same last sector and their size is equal,
they provide exactly the same data, so the name (da0s1, da0s1a, da0s1c)
isn't important at all.
- Provide backward compatibility.
- Update copyright's year.

MFC after: 1 week

merge from geom_vol_ffs.c rev 1.14 (avoid unaligned I/O requests)

Only allow for unloading when there are no geoms in LABEL GEOM class.
We have to use our own destroy_geom method, because default one, which
is a part of geom_slice is broken.
MT5 candidate.

PR: kern/72467
Submitted by: Vladimir Novoseltsev

This is not needed anymore, it is forced in GEOM now.
Actually, it can even cause some problems, because GEOM requires sectorsize
to be more than 0 on first access, not on provider creation, so we can skip
valid providers by doing this check here.

Reported by: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
Sven Willenberger <sven@dmv.com>

Allow to configure debug level from /boot/loader.conf.

Skip providers with not defined sector size.

Reported by: kuriyama

Do not use g_wither_geom(9). I doesn't work in the way which is expected
here anymore (after g_wither_washer() was introduced), i.e. geom and consumer
will not be immediately destroyed if possible.

Tag all geom classes in the tree with a version number.

Remove unused macro.

Decrease log level of one debug message, so there is no hole (level 2
wasn't used at all).

Add missing argument.

Properly free resources if g_access() fails.

- Add 'stop' command, which works just like 'destroy' command, but sounds
less dangerous.
- Update manual pages and extend examples.
- Bump versions.

Introduce GEOM_LABEL class.
This class is used for detecting volume labels on file systems:
UFS, MSDOSFS (FAT12, FAT16, FAT32) and ISO9660.
It also provide native labelization (there is no need for file system).

g_label_ufs.c is based on geom_vol_ffs from Gordon Tetlow.
g_label_msdos.c and g_label_iso9660.c are probably hacks, I just found
where volume labels are stored and I use those offsets here,
but with this class it should be easy to do it as it should be done by
someone who know how.
Implementing volume labels detection for other file systems also should
be trivial.

New providers are created in those directories:
/dev/ufs/ (UFS1, UFS2)
/dev/msdosfs/ (FAT12, FAT16, FAT32)
/dev/iso9660/ (ISO9660)
/dev/label/ (native labels, configured with glabel(8))

Manual page cleanups and some comments inside were submitted by
Simon L. Nielsen, who was, as always, very helpful. Thanks!