Commit Graph

2136 Commits

Author SHA1 Message Date
glebius
7ee1aa34d4 Allocate pager bufs from UMA instead of 80-ish mutex protected linked list.
o In vm_pager_bufferinit() create pbuf_zone and start accounting on how many
  pbufs are we going to have set.
  In various subsystems that are going to utilize pbufs create private zones
  via call to pbuf_zsecond_create(). The latter calls uma_zsecond_create(),
  and sets a limit on created zone. After startup preallocate pbufs according
  to requirements of all pbuf zones.

  Subsystems that used to have a private limit with old allocator now have
  private pbuf zones: md(4), fusefs, NFS client, smbfs, VFS cluster, FFS,
  swap, vnode pager.

  The following subsystems use shared pbuf zone: cam(4), nvme(4), physio(9),
  aio(4). They should have their private limits, but changing that is out of
  scope of this commit.

o Fetch tunable value of kern.nswbuf from init_param2() and while here move
  NSWBUF_MIN to opt_param.h and eliminate opt_swap.h, that was holding only
  this option.
  Default values aren't touched by this commit, but they probably should be
  reviewed wrt to modern hardware.

This change removes a tight bottleneck from sendfile(2) operation, that
uses pbufs in vnode pager. Other pagers also would benefit from faster
allocation.

Together with:	gallatin
Tested by:	pho
2019-01-15 01:02:16 +00:00
mckusick
e73f4235a2 Move ASSERT_VOP_LOCKED to top of ufs_vinit() as it should be true
when the function is entered.

Suggested by: kib
2018-12-30 06:03:20 +00:00
mckusick
63f92e6bd1 For consistency with FFS2's fifoops2 and both versions of FFS's
vnodeops make FFS1's fifoops1 use ffs_lock. Also delete ffs_reallocblks
from fifoops1 which is needed only for fifoops2 because of its
support for extended attributes that need to allocate blocks.

Suggested by: kib
2018-12-30 05:03:41 +00:00
mckusick
51739d277b When loading an inode from disk, verify that its mode is valid.
If invalid, return EINVAL. Note that inode check-hashes greatly
reduce the chance that these errors will go undetected.

Reported by:  Christopher Krah <krah@protonmail.com>
Reported as:  FS-5-UFS-2: Denial Of Service in nmount-3 (ffs_read)
Reviewed by:  kib
MFC after:    1 week
Sponsored by: Netflix

M    sys/fs/ext2fs/ext2_vnops.c
M    sys/kern/vfs_subr.c
M    sys/ufs/ffs/ffs_snapshot.c
M    sys/ufs/ufs/ufs_vnops.c
2018-12-27 07:18:53 +00:00
kib
c93608ca18 Allocate v_object for the new snapshot vnode.
The vnode is not opened, so it ends up with the malloced buffers otherwise.

Reported and tested by:	pho
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2018-12-23 18:54:09 +00:00
mckusick
bfbf739aad Ensure that the inode check-hash is not left zeroed out in the case where
the check-hash fails. Prior to the fix in -r342133 the inode with the
zeroed out check-hash was written back to disk causing further confusion.

Reported by:  Gary Jennejohn (gj)
Sponsored by: Netflix
2018-12-15 18:49:30 +00:00
mckusick
b27d4425e8 Reorder ffs_verify_dinode_ckhash() so that it checks the inode check-hash
before copying in the inode so that the mode and link-count are not set
if the check-hash fails. This change ensures that the vnode will be properly
unwound and recycled rather than being held in the cache.

Initialize the file mode is zero so that if the loading of the inode
fails (for example because of a check-hash failure), the vnode will be
properly unwound and recycled.

Reported by:  Gary Jennejohn (gj)
Sponsored by: Netflix
2018-12-15 18:35:46 +00:00
mckusick
c376c8363f Must set ip->i_effnlink = ip->i_nlink to avoid a soft updates
"panic: softdep_update_inodeblock: bad link count" when releasing
a partially initialized vnode after an inode check-hash failure.

Reported by:  Gary Jennejohn <gljennjohn@gmail.com>
Reported by:  Peter Holm (pho)
Sponsored by: Netflix
2018-12-15 17:58:42 +00:00
mckusick
830a63af76 Continuing efforts to provide hardening of FFS. This change adds a
check hash to the filesystem inodes. Access attempts to files
associated with an inode with an invalid check hash will fail with
EINVAL (Invalid argument). Access is reestablished after an fsck
is run to find and validate the inodes with invalid check-hashes.
This check avoids a class of filesystem panics related to corrupted
inodes. The hash is done using crc32c.

Note this check-hash is for the inode itself and not any of its
indirect blocks. Check-hash validation may be extended to also
cover indirect block pointers, but that will be a separate (and
more costly) feature.

Check hashes are added only to UFS2 and not to UFS1 as UFS1 is
primarily used in embedded systems with small memories and low-powered
processors which need as light-weight a filesystem as possible.

Reviewed by:  kib
Tested by:    Peter Holm
Sponsored by: Netflix
2018-12-11 22:14:37 +00:00
mjg
7e31d1de7e Remove unused argument to priv_check_cred.
Patch mostly generated with cocinnelle:

@@
expression E1,E2;
@@

- priv_check_cred(E1,E2,0)
+ priv_check_cred(E1,E2)

Sponsored by:	The FreeBSD Foundation
2018-12-11 19:32:16 +00:00
mckusick
a394bed4ee If the vfs.ffs.dotrimcons sysctl option is enabled while a file
deletion is active, specifically after a call to ffs_blkrelease_start()
but before the call to ffs_blkrelease_finish(), ffs_blkrelease_start()
will have handed out SINGLETON_KEY rather than starting a collection
sequence. Thus if we get a SINGLETON_KEY passed to ffs_blkrelease_finish(),
we just return rather than trying to finish the nonexistent sequence.

Reported by:  Warner Losh (imp@)
Sponsored by: Netflix
2018-12-06 01:04:56 +00:00
mckusick
2c9178edde Normally when an attempt is made to mount a UFS/FFS filesystem whose
superblock has a check-hash error, an error message noting the
superblock check-hash failure is printed and the mount fails. The
administrator then runs fsck to repair the filesystem and when
successful, the filesystem can once again be mounted.

This approach fails if the filesystem in question is a root filesystem
from which you are trying to boot. Here, the loader fails when trying
to access the filesystem to get the kernel to boot. So it is necessary
to allow the loader to ignore the superblock check-hash error and make
a best effort to read the kernel. The filesystem may be suffiently
corrupted that the read attempt fails, but there is no harm in trying
since the loader makes no attempt to write to the filesystem.

Once the kernel is loaded and starts to run, it attempts to mount its
root filesystem. Once again, failure means that it breaks to its prompt
to ask where to get its root filesystem. Unless you have an alternate
root filesystem, you are stuck.

Since the root filesystem is initially mounted read-only, it is
safe to make an attempt to mount the root filesystem with the failed
superblock check-hash. Thus, when asked to mount a root filesystem
with a failed superblock check-hash, the kernel prints a warning
message that the root filesystem superblock check-hash needs repair,
but notes that it is ignoring the error and proceeding. It does
mark the filesystem as needing an fsck which prevents it from being
enabled for writing until fsck has been run on it. The net effect
is that the reboot fails to single user, but at least at that point
the administrator has the tools at hand to fix the problem.

Reported by:    Rick Macklem (rmacklem@)
Discussed with: Warner Losh (imp@)
Sponsored by:   Netflix
2018-12-06 00:09:39 +00:00
mckusick
be83b5d4e3 Move the check for the filesystem having been run on a kernel that
predates metadata check hashes so that it is done before deciding
whether to compute a check-hash of the superblock.

Reported by:  Rick Macklem <rmacklem@uoguelph.ca>
Sponsored by: Netflix
2018-11-26 00:58:07 +00:00
mckusick
3216726186 Calculate updated superblock check-hash before writing it into the snapshot.
This corrects a bug that prevented snapshots from being mounted due to a
superblock check-hash failure.

Reported by:  Brennan Vincent <brennan@umanwizard.com>
Tested by:    Peter Holm (pho@)
Sponsored by: Netflix
2018-11-25 18:01:15 +00:00
markj
d08f717585 Ensure that directory entry padding bytes are zeroed.
Directory entries must be padded to maintain alignment; in many
filesystems the padding was not initialized, resulting in stack
memory being copied out to userspace.  With the ino64 work there
are also some explicit pad fields in struct dirent.  Add a subroutine
to clear these bytes and use it in the in-tree filesystems.  The
NFS client is omitted for now as it was fixed separately in r340787.

Reported by:	Thomas Barabosch, Fraunhofer FKIE
Reviewed by:	kib
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
2018-11-23 22:24:59 +00:00
kib
7d33ec3750 Add d_off support for multiple filesystems.
The d_off field has been added to the dirent structure recently.
Currently filesystems don't support this feature.  Support has been
added and tested for zfs, ufs, ext2fs, fdescfs, msdosfs and unionfs.
A stub implementation is available for cd9660, nandfs, udf and
pseudofs but hasn't been tested.

Motivation for this feature: our usecase is for a userspace nfs server
(nfs-ganesha) with zfs.  At the moment we cache direntry offsets by
calling lseek once per entry, with this patch we can get the offset
directly from getdirentries(2) calls which provides a significant
speedup.

Submitted by:	Jack Halford <jack@gandi.net>
Reviewed by:	mckusick, pfg, rmacklem (previous versions)
Sponsored by:	Gandi.net
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D17917
2018-11-14 14:18:35 +00:00
mckusick
80199cdcb4 In preparation for adding inode check-hashes, clean up and
document the libufs interface for fetching and storing inodes.
The undocumented getino / putino interface has been replaced
with a new getinode / putinode interface.

Convert the utilities that had been using the undocumented
interface to use the new documented interface.

No functional change (as for now the libufs library does not
do inode check-hashes).

Reviewed by:  kib
Tested by:    Peter Holm
Sponsored by: Netflix
2018-11-13 21:40:56 +00:00
brooks
7698ed5201 Make vop_symlink take a const target path.
This will enable callers to take const paths as part of syscall
decleration improvements.

Where doing so is easy and non-distruptive carry the const through
implementations. In UFS the value is passed to an interface that must
take non-const values. In ZFS, const poisoning would touch code shared
with upstream and it's not worth adding diffs.

Bump __FreeBSD_version for external API consumers.

Reviewed by:	kib (prior version)
Obtained from:	CheriBSD
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D17805
2018-11-02 14:42:36 +00:00
kib
de9d57cf38 Implement O_BENEATH and AT_BENEATH.
Flags prevent open(2) and *at(2) vfs syscalls name lookup from
escaping the starting directory.  Supposedly the interface is similar
to the same proposed Linux flags.

Reviewed by:	jilles (code, previous version of manpages), 0mp (manpages)
Discussed with:	allanjude, emaste, jonathan
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D17547
2018-10-25 22:16:34 +00:00
mckusick
ce1bca43e9 Continuing efforts to provide hardening of FFS, this change adds a
check hash to the superblock. If a check hash fails when an attempt
is made to mount a filesystem, the mount fails with EINVAL (Invalid
argument). This avoids a class of filesystem panics related to
corrupted superblocks. The hash is done using crc32c.

Check hases are added only to UFS2 and not to UFS1 as UFS1 is primarily
used in embedded systems with small memories and low-powered processors
which need as light-weight a filesystem as possible.

Reviewed by:  kib
Tested by:    Peter Holm
Sponsored by: Netflix
2018-10-23 21:10:06 +00:00
kib
1d18e5f10a Correct panic messages.
Reviewed by:	mckusick
Sponsored by:	The FreeBSD Foundation
Approved by:	re (rgrimes)
MFC after:	1 week
2018-09-22 17:05:49 +00:00
kib
610ca65f57 Fix state of dquot-less vnodes after failed quotaoff.
UFS quotaoff iterates over all mp vnodes, and derefences and clears
the pointers to corresponding dquots. If SU work items transiently
reference some of dquots,quotaoff() would eventually fail, but all
processed vnodes are already stripped from dquots.  The state is
problematic, since quotas are left enabled, but there is no dquots
where blocks and inodes can be accounted.  The result is assertion
failures and NULL pointer dereferences.

Fix it by suspending writes around quotaoff() call.  Since the
filesystem is synced, no dandling references to dquots from SU
workitems can left behind, which means that quotaoff succeeds.

The complication there is that quotaoff VFS op is performed with the
mount point busied, while to suspend, we need to start write on the
mp.  If vn_start_write() is called on busied mp, system might deadlock
against parallel unmount request.  Handle this by unbusy-ing mp before
starting write, which in turn requires changing the quotaoff()
interface to return with the mount point not busied, same as was done
for quotaon().

Reviewed by:	mckusick
Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
Approved by:	re (gjb)
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D17208
2018-09-19 14:36:57 +00:00
kib
eb43bb633e Do not upgrade the vnode lock to call getinoquota().
Doing so can deadlock when the thread already owns another vnode lock,
e.g. during a rename, as was demonstrated by the reporter.  In fact,
there seems to be no need to force the call to getinoquota() always,
because vn_open() locks vnode exclusively, and this is the most
important case.  To add to the point, directories where the dirent is
added or removed, are locked exclusively as well.

Reported by:	bwidawsk
Tested by:	bwidawsk, pho (as part of the larger patch)
Sponsored by:	The FreeBSD Foundation
Approved by:	re (gjb)
MFC after:	1 week
2018-09-17 19:38:43 +00:00
mckusick
a81473809a The Call For Testing had no reports of operational problems and
found that performance was no worse and usually better when running
with TRIM consolidation. Performance improvement was most noticable
when multiple large files are released in a short period of time.

Thus, TRIM consolidation is being enabled by default. Should
operational problems be found, it can be disabled using the command
`sysctl vfs.ffs.dotrimcons=0'. This variable can also be set as a
tunable if early disabling is necessary.

Approved by:  re (gjb)
Sponsored by: Netflix
2018-09-06 23:28:35 +00:00
markm
d8723e8b03 Remove the Yarrow PRNG algorithm option in accordance with due notice
given in random(4).

This includes updating of the relevant man pages, and no-longer-used
harvesting parameters.

Ensure that the pseudo-unit-test still does something useful, now also
with the "other" algorithm instead of Yarrow.

PR:		230870
Reviewed by:	cem
Approved by:	so(delphij,gtetlow)
Approved by:	re(marius)
Differential Revision:	https://reviews.freebsd.org/D16898
2018-08-26 12:51:46 +00:00
mckusick
411de280b9 Proper spelling of consolidation.
Submitted by: Dimitry Andric
2018-08-23 22:35:14 +00:00
mckusick
a91193512d TRIM consolodation is supposed to be off by default 2018-08-20 21:19:21 +00:00
mckusick
34b26921fe For traditional disks, the filesystem attempts to allocate the
blocks of a file as contiguously as possible. Since the filesystem
does not know how large a file will grow when it is first being
written, it initially places the file in a set of blocks in which
it currently fits. As it grows, it is relocated to areas with
larger contiguous blocks.  In this way it saves its large contiguous
sets of blocks for the files that need them and thus avoids
unnecessaily fragmenting its disk space.

We used to skip reallocating the blocks of a file into a contiguous
sequence if the underlying flash device requested BIO_DELETE
notifications, because devices that benefit from BIO_DELETE also
benefit from not moving the data. However, in the algorithm described
above that reallocates the blocks, the destination for the data is
usually moved before the data is written to the initially allocated
location. So we rarely suffer the penalty of extra writes.  With
the addition of the consolodation of contiguous blocks into single
BIO_DELETE operations, having fewer but larger contiguous blocks
reduces the number of (slow and expensive) BIO_DELETE operations.
So when doing BIO_DELETE consolodation, we do block reallocation.

Reviewed by:  kib
Tested by:    Peter Holm
Sponsored by: Netflix
2018-08-19 17:19:20 +00:00
mckusick
e602de7470 Add consolodation of TRIM / BIO_DELETE commands to the UFS/FFS filesystem.
When deleting files on filesystems that are stored on flash-memory
(solid-state) disk drives, the filesystem notifies the underlying
disk of the blocks that it is no longer using. The notification
allows the drive to avoid saving these blocks when it needs to
flash (zero out) one of its flash pages. These notifications of
no-longer-being-used blocks are referred to as TRIM notifications.
In FreeBSD these TRIM notifications are sent from the filesystem
to the drive using the BIO_DELETE command.

Until now, the filesystem would send a separate message to the drive
for each block of the file that was deleted. Each Gigabyte of file
size resulted in over 3000 TRIM messages being sent to the drive.
This burst of messages can overwhelm the drive's task queue causing
multiple second delays for read and write requests.

This implementation collects runs of contiguous blocks in the file
and then consolodates them into a single BIO_DELETE command to the
drive. The BIO_DELETE command describes the run of blocks as a
single large block being deleted. Each Gigabyte of file size can
result in as few as two BIO_DELETE commands and is typically less
than ten.  Though these larger BIO_DELETE commands take longer to
run, they do not clog the drive task queue, so read and write
commands can intersperse effectively with them.

Though this new feature has been throughly reviewed and tested, it
is being added disabled by default so as to minimize the possibility
of disrupting the upcoming 12.0 release. It can be enabled by running
``sysctl vfs.ffs.dotrimcons=1''. Users are encouraged to test it.
If no problems arise, we will consider requesting that it be enabled
by default for 12.0.

Reviewed by:  kib
Tested by:    Peter Holm
Sponsored by: Netflix
2018-08-19 16:56:42 +00:00
mckusick
3b4b479fff Replace the TRIM consolodation framework originally added in -r337396
driven by problems found with the algorithms being tested for TRIM
consolodation.

Reported by:  Peter Holm
Suggested by: kib
Reviewed by:  kib
Sponsored by: Netflix
2018-08-18 22:21:59 +00:00
mckusick
8a71ad7c3d Revert -r337396. It is being replaced with a revised interface that
resulted from testing and further reviews.
2018-08-18 21:21:06 +00:00
jamie
94a36bb7c1 Put jail(2) under COMPAT_FREEBSD11. It has been the "old" way of creating
jails since FreeBSD 7.

Along with the system call, put the various security.jail.allow_foo and
security.jail.foo_allowed sysctls partly under COMPAT_FREEBSD11 (or
BURN_BRIDGES).  These sysctls had two disparate uses: on the system side,
they were global permissions for jails created via jail(2) which lacked
fine-grained permission controls; inside a jail, they're read-only
descriptions of what the current jail is allowed to do.  The first use
is obsolete along with jail(2), but keep them for the second-read-only use.

Differential Revision:	D14791
2018-08-16 18:40:16 +00:00
mckusick
e7f491b70c Put in place the framework for consolodating contiguous blocks into
a smaller number of larger TRIM requests. The hope had been to have
the full TRIM consolodation in place for 12.0, but the algorithms
are still under development and need further testing. With this
framework in place it will be possible to easily add TRIM consolodation
once the optimal strategy has been found.

The only functional change with this patch is the elimination of TRIM
requests for blocks that are freed before they have been likely to
have been written.

Reviewed by: kib
Discussed with: Warner Losh and Chuck Silvers
Sponsored by: Netflix
2018-08-06 21:09:11 +00:00
kib
6babc396a9 Avoid assertion in /dev/ufssuspend when the suspend ioctl is
(incorrectly) called while another suspension is already active.

PR:	230220
Reported by:	dexuan
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2018-08-01 19:06:55 +00:00
asomers
b3776cb8de Make timespecadd(3) and friends public
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.

Our kernel currently defines two-argument versions of timespecadd and
timespecsub.  NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions.  Solaris also defines a three-argument version, but
only in its kernel.  This revision changes our definition to match the
common three-argument version.

Bump _FreeBSD_version due to the breaking KPI change.

Discussed with:	cem, jilles, ian, bde
Differential Revision:	https://reviews.freebsd.org/D14725
2018-07-30 15:46:40 +00:00
mckusick
9be123d7f3 Add needed locking for um_flags added in -r335808.
While here document required locking details in ufsmount structure.

Reported by: kib
Reviewed by: kib
2018-07-17 04:43:58 +00:00
cem
289d156e0e ffs_syncvnode: Remove unhelpful print
It can occur during ordinary use of softupdates, or perhaps if writes to the
underlying media fail (causing bufs to be redirtied).  Either way, it is not
particularly actionable.

Reviewed by:	imp, kib
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D16258
2018-07-14 15:45:11 +00:00
mckusick
658dc4c073 Import commit from NetBSD with checkin message:
Avoid Undefined Behavior in ffs_clusteracct()

    Change the type of 'bit' variable from int to unsigned int and use unsigned
    values consistently.

    sys/ufs/ffs/ffs_subr.c:336:10, shift exponent -1 is negative

    Detected with Kernel Undefined Behavior Sanitizer.

    Reported by <Harry Pantazis>

Submitted by: Pedro Giffuni
2018-07-07 19:11:43 +00:00
mckusick
e7f8a661a2 Create um_flags in the ufsmount structure to hold flags for a UFS filesystem.
Convert integer structure flags to use um_flags:

	int	um_candelete;			/* devvp supports TRIM */
	int	um_writesuspended;		/* suspension in progress */

become:

#define UM_CANDELETE		0x00000001	/* devvp supports TRIM */
#define UM_WRITESUSPENDED	0x00000002	/* suspension in progress */

This is in preparation for adding other flags to indicate forcible
unmount in progress after a disk failure and possibly forcible
downgrade to read-only.

No functional change intended.

Sponsored by:	Netflix
2018-06-29 22:24:41 +00:00
imp
2ed7d0a436 Use buf + strategy rather than bypassing geom_vfs layer
The reference counting that's done in the geom_vfs layer to prevent
delivery of requests to defunct devices only works if all requests go
through that layer. UFS was bypassing that layer for BIO_DELETE requests,
sending them to the geom_consumer directly with g_io_request. Allocate
a buf, fill it in, and call strategy on it instead.

Submitted by: Chuck Silvers
Reviewed by: scottl, imp, kirk
Sponsored by: Netflix
Differential: https://reviews.freebsd.org/D15456
2018-06-26 00:39:38 +00:00
mmacy
e452eba561 ufs: remove cgbno variable where unused 2018-05-19 19:30:42 +00:00
mckusick
4b68405396 Fix warning found by Coverity.
CID 1009353:  Error handling issues  (CHECKED_RETURN)
2018-05-16 23:42:02 +00:00
kib
57921f916a Detect and optimize reads from the hole on UFS.
- Create getblkx(9) variant of getblk(9) which can return error.
- Add GB_NOSPARSE flag for getblk()/getblkx() which requests that BMAP
  was performed before the buffer is created, and EJUSTRETURN returned
  in case the requested block does not exist.
- Make ffs_read() use GB_NOSPARSE to avoid instantiating buffer (and
  allocating the pages for it), copying from zero_region instead.

The end result is less page allocations and buffer recycling when a
hole is read, which is important for some benchmarks.

Requested and reviewed by:	jeff
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D14917
2018-05-13 09:47:28 +00:00
mckusick
50d7ca2454 Renumber soft-update types starting at 1 instead of 0 to avoid confusion
of zero'ed memory appearing to have a valid soft-update type.

Also correct some comments.

Reviewed by: kib
2018-04-05 00:32:01 +00:00
emaste
61bad5ab72 Revert r313780 (UFS_ prefix) 2018-03-17 12:59:55 +00:00
emaste
e23f2eb452 Prefix UFS symbols with UFS_ to reduce namespace pollution
Followup to r313780.  Also prefix ext2's and nandfs's versions with
EXT2_ and NANDFS_.

Reported by:	kib
Reviewed by:	kib, mckusick
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D9623
2018-03-17 01:48:27 +00:00
mckusick
ea7d671565 This change is some refactoring of Mark Johnston's changes in r329375
to fix the memory leak that I introduced in r328426. Instead of
trying to clear up the possible memory leak in all the clients, I
ensure that it gets cleaned up in the source (e.g., ffs_sbget ensures
that memory is always freed if it returns an error).

The original change in r328426 was a bit sparse in its description.
So I am expanding on its description here (thanks cem@ and rgrimes@
for your encouragement for my longer commit messages).

In preparation for adding check hashing to superblocks, r328426 is
a refactoring of the code to get the reading/writing of the superblock
into one place. Unlike the cylinder group reading/writing which
ends up in two places (ffs_getcg/ffs_geom_strategy in the kernel
and cgget/cgput in libufs), I have the core superblock functions
just in the kernel (ffs_sbfetch/ffs_sbput in ffs_subr.c which is
already imported into utilities like fsck_ffs as well as libufs to
implement sbget/sbput). The ffs_sbfetch and ffs_sbput functions
take a function pointer to do the actual I/O for which there are
four variants:

    ffs_use_bread / ffs_use_bwrite for the in-kernel filesystem

    g_use_g_read_data / g_use_g_write_data for kernel geom clients

    ufs_use_sa_read for the standalone code (stand/libsa/ufs.c
	but not stand/libsa/ufsread.c which is size constrained)

    use_pread / use_pwrite for libufs

Uses of these interfaces are in the UFS filesystem, geoms journal &
label, libsa changes, and libufs. They also permeate out into the
filesystem utilities fsck_ffs, newfs, growfs, clri, dump, quotacheck,
fsirand, fstyp, and quot. Some of these utilities should probably be
converted to directly use libufs (like dumpfs was for example), but
there does not seem to be much win in doing so.

Tested by: Peter Holm (pho@)
2018-03-02 04:34:53 +00:00
cem
d0850a5df2 ffs: softdep_disk_write_complete: Quiesce spurious Coverity warning
Coverity cannot determine that handle_written_indirdep() does not access
uninitialized 'sbp' when flags argument is zero.

So, simply move the initialization slightly sooner to silence the warning.

No functional change.

Reported by:	Coverity
Sponsored by:	Dell EMC Isilon
2018-03-01 00:29:52 +00:00
mckusick
0057f01722 Use a more straight-forward approach to relaxing the location
restraints when validating one of the backup superblocks.
2018-02-26 00:34:56 +00:00
mckusick
6baa29ff24 Relax the location restraints when validating one of the
backup superblocks.
2018-02-24 03:33:46 +00:00