In this particular instance the allocation occurred in the context
of sys_msync()->...->zpl_putpage() where we must be careful not to
initiate additional I/O.
Signed-off-by: Massimo Maggi <massimo@mmmm.it>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Allow the zfs_txg_timeout variable to be dynamically tuned at run
time. By pulling it down out of the variable declaration it will
be evaluted each time through the loop.
The zfs_txg_timeout variable is now declared extern in a the common
sys/txg.h header rather than locally in dsl_scan.c. This prevents
potential type mismatches if the global variable needs to be used
elsewhere.
Move the module_param() code in to the same source file where
zfs_txg_timeout is declared. This is the most logical location.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Commit c409e4647f introduced a
number of module parameters. This required several types to be
changed to accomidate the required module parameters Linux macros.
Unfortunately, arc.c contained its own extern definition of the
zfs_write_limit_max variable and its type was not updated to be
consistent with its dsl_pool.c counterpart. If the variable had
been properly marked extern in a common header, then gcc would
have generated a warning and this would not have slipped through.
The result of this was that the ARC unconditionally expected
zfs_write_limit_max to be 64-bit. Unfortunately, the largest size
integer module parameter that Linux supports is unsigned long, which
varies in size depending on the host system's native word size. The
effect was that on 32-bit systems, ARC incorrectly performed 64-bit
operations on a 32-bit value by reading the neighboring 32 bits as
the upper 32 bits of the 64-bit value.
We correct that by changing the extern declaration to use the unsigned
long type and move these extern definitions in to the common arc.h
header. This should make ARC correctly treat zfs_write_limit_max as a
32-bit value on 32-bit systems.
Reported-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#749
zfs_immediate_write_sz variable is a tunable, but lacks proper
module_param() instrumentation.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1032
Term 'transaction group' is commonly abbreviated as txg in ZFS sources.
There are some places (Linux specific MODULE_PARAM_DESC() macros)
where it is incorrectly spelled as 'tgx'.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1030
It doesn't make sense for a zvol to use the default system I/O
scheduler because it is a virtual device. Therefore, we change
the default scheduler to 'noop' for zvols provided that the
elevator_change() function is available. This interface has
been available since Linux 2.6.36 and appears in the RHEL 6.x
kernels.
We deliberately do not implement the method for older kernels
because it was racy and could result in system crashes. It's
better to simply manually tune the scheduler for these kernels.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1017
This adds an interface to "punch holes" (deallocate space) in VFS
files. The interface is identical to the Solaris VOP_SPACE interface.
This interface is necessary for TRIM support on file vdevs.
This is implemented using Linux fallocate(FALLOC_FL_PUNCH_HOLE), which
was introduced in 2.6.38. For a brief time before 2.6.38 this was done
using the truncate_range inode operation, which was quickly deprecated.
This patch only supports FALLOC_FL_PUNCH_HOLE.
This adds support for the truncate_range() inode operation to
VOP_SPACE() for file hole punching. This API is deprecated and removed
in 3.5, so it's only useful for old kernels.
On tmpfs, the truncate_range() inode operation translates to
shmem_truncate_range(). Unfortunately, this function expects the end
offset to be inclusive and aligned to the end of a page. If it is not,
the kernel will stop with a BUG_ON().
This patch fixes the issue by adapting to the constraints set forth by
shmem_truncate_range().
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#168
Currently, when processing DISCARD requests, zvol_discard() calls
dmu_free_long_range() with the precise offset and size of the request.
Unfortunately, this is not optimal for requests that are not aligned to
the zvol block boundaries. Indeed, in the case of an unaligned range,
dnode_free_range() will zero out the unaligned parts. Not only is this
useless since we are not freeing any space by doing so, it is also slow
because it translates to a read-modify-write operation.
This patch fixes the issue by rounding up the discard start offset to
the next volume block boundary, and rounding down the discard end
offset to the previous volume block boundary.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1010
This branch is a port of the ztest backwards compatibility
testing option. It includes the original upstream Illumos
patch plus several followup patches to address concerns in
the original change.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The realpath(3) function expects that when a buffer is passed
for the 'resolved_path' that it be at least PATH_MAX in length.
If it's not a buffer overflow may occur.
Therefore the passed buffer size is changed from MAXNAMELEN to
MAXPATHLEN. We also take this opertunity to dynamically allocate
the buffer to keep it off the stack.
warning: call to '__realpath_chk_warn' declared with attribute
warning: second argument of realpath must be either NULL or at
least PATH_MAX bytes long buffer [enabled by default]
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Under Linux the following functions are flagged with the
attribute warn_unused_result, this triggers a warning when
ever they are used without checking the return value.
To handle this case we check the result VERIFY(). It's
better to detect this immediately on failure rather than
segfault farther down in the function.
../../cmd/ztest/ztest.c:6033:2: warning:
ignoring return value of 'asprintf', declared with
attribute warn_unused_result [-Wunused-result]
../../cmd/ztest/ztest.c:739:3: warning:
ignoring return value of 'realpath', declared with
attribute warn_unused_result [-Wunused-result]
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The use of tempnam() is racy and it should be avoided in favor of
mkstemp(). According to the Linux tempnam(3) man page.
"Although tempnam() generates names that are difficult to guess,
it is nevertheless possible that between the time that tempnam()
returns a pathname, and the time that the program opens it, another
program might create that pathname using open(2), or create it as
a symbolic link. This can lead to security holes. To avoid such
possibilities, use the open(2) O_EXCL flag to open the pathname.
Or better yet, use mkstemp(3) or tmpfile(3)."
This issue was flagged by gcc.
ztest.o: In function `setup_data_fd': cmd/ztest/ztest.c:5822:
warning: the use of `tempnam' is dangerous, better use `mkstemp'
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
To ensure ztest behaves as similarly as possible to the kernel
implementation of ZFS we attempt to honor the kernel stack limits.
This includes keeping the individual stack frame sizes under 1K
in size. We currently use gcc to detect and enforce this limit.
Therefore to get this building cleanly with full debugging enabled
the stack usage in the following functions has been reduced by
moving the buffer to the heap.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Currently, ztest expects to get 3 and 4 as the file descriptors for
data and random files, respectively. This is quite fragile and breaks
easily if ztest is run with these file descriptors already opened
(e.g. in a complex shell script).
This patch fixes the issue by removing the assumptions on the file
descriptor numbers that open() returns.
For the random file (/dev/urandom), the new code doesn't rely on a
shared file descriptor; instead, it reopens the file in the child.
For the data file, the new code writes the file descriptor number into
a "ZTEST_FD_DATA" environment variable so that it can be recovered
after the execv() call.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
illumos/illumos-gate@ad135b5d64
Illumos changeset: 13700:2889e2596bd6
Note that this is only a partial port of the aforementioned Illumos
changeset.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <gwilson@delphix.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Reviewed by: Dan Kruchinin <dan.kruchinin@gmail.com>
Approved by: Eric Schrock <Eric.Schrock@delphix.com>
Ported to zfsonlinux by: Etienne Dechamps <etienne.dechamps@ovh.net>
This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim. See commit b8d06fc for additional details.
SPL: Fixing allocation for task txg_sync (6093) which
used GFP flags 0x297bda7c with PF_NOFS set
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1002
illumos/illumos-gate@2e2c135528
Illumos changeset: 13780:6da32a929222
3100 zvol rename fails with EBUSY when dirty
Reviewed by: Christopher Siden <chris.siden@delphix.com>
Reviewed by: Adam H. Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Eric Schrock <eric.schrock@delphix.com>
Ported-by: Etienne Dechamps <etienne.dechamps@ovh.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#995
Currently, ztest fails with the following error:
error: Pool 'ztest' has encountered an uncorrectable I/O failure
and the failure mode property for this pool is set to panic.
We know how to fix it (see issue #939), but it may take some time
before we get around to merging the fix, which has some heavy
dependencies.
In the mean time, it is not ideal to be unable to use ztest just
because of a small isolated issue, so this patch works around the
problem by disabling the reguid test. This is just a temporary hack to
keep ztest usable.
The reguid test will be enabled again when the proper fix is merged.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#997
Currently, in several instances (but not all), ztest generates vdev
file paths using a statement similar to this:
snprintf(path, sizeof (path), ztest_dev_template, ...);
This worked fine until 40b84e7aec, which
changed path to be a pointer to the heap instead of an array allocated
on the stack. Before this change, sizeof(path) would return the size of
the array; now, it returns the size of the pointer instead.
As a result, the aforementioned sprintf statement uses the wrong size
and truncates the vdev file path to the first 4 or 8 bytes (depending
on the architecture). Typically, with default settings, the file path
will become "/tmp/zt" instead of "/test/ztest.XXX".
This issue only exists in ztest_vdev_attach_detach() and
ztest_fault_inject(), which explains why ztest doesn't fail right away.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #989
Currently, for unknown reasons, VOP_CLOSE() is a no-op in userspace.
This causes file descriptor leaks. This is especially problematic with
long ztest runs, since zpool.cache is opened repeatedly and never
closed, resulting in resource exhaustion (EMFILE errors).
This patch fixes the issue by making VOP_CLOSE() do what it is supposed
to do.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #989
Currently, thread_create(), when called in userspace, creates a
joinable (i.e. not detached thread). This is the pthread default.
Unfortunately, this does not reproduce kthreads behavior (kthreads
are always detached). In addition, this contradicts the original
Solaris code which creates userspace threads in detached mode.
These joinable threads are never joined, which leads to a leakage of
pthread thread objects ("zombie threads"). This in turn results in
excessive ressource consumption, and possible ressource exhaustion in
extreme cases (e.g. long ztest runs).
This patch fixes the issue by creating userspace threads in detached
mode. The only exception is ztest worker threads which are meant to be
joinable.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #989
As of Linux 2.6.36 an elevator_change() interface was added.
This commit updates vdev_elevator_switch() to use this interface
when available, otherwise it falls back to the usermodehelper
method.
Original-patch-by: foobarz <sysop@xeon.(none)>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#906
Currently, mkfs.ext2 on zconfig.sh zvols tries to use a 8K blocksize,
probably because by default zvol exposes an optimal I/O size of 8K.
Unfortunately, a ext2 blocksize of 8K is not supported by the kernel,
so the resulting filesystem is unmountable.
This patch fixes the issue by making sure the blocksize is 4K. We have
to use -F to force it else mkfs.ext2 won't allow us to use a blocksize
smaller than the optimal I/O size.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#979
In order to implement synchronous NFS metadata semantics ZFS
needs to provide the .commit_metadata hook. All it takes there
is to make sure changes are committed to ZIL. Fortunately
zfs_fsync() does just that, so simply calling it from
zpl_commit_metadata() does the trick.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#969
Previously we returned ERR_PTR(-ENOENT) which the rest of the kernel
doesn't expect and as such we can oops.
Signed-off-by: Chris Wedgwood <cw@f00f.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#949Closes#931Closes#789Closes#743Closes#730
This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim. See commit b8d06fca08
for additional details.
SPL: Fixing allocation for task txg_sync (6093) which
used GFP flags 0x297bda7c with PF_NOFS set
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #973
Introduced by commit 44867b6d6e.
We should of course check to ensure best isn't NULL before
attempting to dereference it.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#974
The goal of this change is to make 'zpool import' prefer to use
the peristent /dev/mapper or /dev/disk/by-* paths. These are far
preferable to the devices in /dev/ whos names are not persistent
and are determined by the order in which a device is detected.
This patch improves things by changing the default search path from
just to the top level /dev/ directory to (in order):
/dev/disk/by-vdev - Custom rules, use first if they exist
/dev/disk/zpool - Custom rules, use first if they exist
/dev/mapper - Use multipath devices before components
/dev/disk/by-uuid - Single unique entry and persistent
/dev/disk/by-id - May be multiple entries and persistent
/dev/disk/by-path - Encodes physical location and persistent
/dev/disk/by-label - Custom persistent labels
/dev - UNSAFE device names will change
The default search path can be overriden by setting the
ZPOOL_IMPORT_PATH environment variable. This must be a colon
delimited list of paths which are searched for vdevs. If the
'zpool import -d' option is specified only those listed paths
will be searched.
Finally, when multiple paths to the same device are found. If one
of the paths is an exact match for the path used last time to import
the pool it will be used. When there are no exact matches the
prefered path will be determined by the provided search order.
This means you can still import a pool and force specific names by
providing the -d <path> option. And the prefered names will persist
as long as those paths exist on your system.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#965
This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim. See commit b8d06fca08
for additional details.
SPL: Fixing allocation for task txg_sync (6093) which
used GFP flags 0x297bda7c with PF_NOFS set
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
When zfs_replay_write() replays TX_WRITE records from ZIL
it calls zpl_write_common() to perform the actual write.
zpl_write_common() returns the number of bytes written
(similar to write() system call) or an (negative) error.
However, the code expects the positive return value to be
a residual counter. Thus when zpl_write_common() successfully
completes it is mistakenly considered to be a partial write and
the error code delivered further. At this point the ZIL processing
is aborted with famous "ZFS replay transaction error 5" error
message given to the message buffer.
The fix is to compare the zpl_write_commmon() return value with
the buffer size and flag error only when they disagree.
Signed-off-by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#933
Commit 2b2861362f accidentally
introduced this issue by only conditionally registering the
commit callback in the async case.
The error handing code for the dmu_tx_assign() failure case
relied on there always being a registered commit callback to
clear the PG_writeback bit. Since that is no longer strictly
true for the synchronous case we must explicitly invoke the
callback.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#961
Without this fix the zdb printouts of ZIL data blocks look full of FF
due to printf() handling its arguments as int by default.
Here is the output before the fix
TX_WRITE len 4136, txg 1093817, seq 149231
foid 4242, offset 0, length f68
G FFFFFF8EFFFFFF87FFFFFF91FFFFFFCC 1c
FFFFFFAFFFFFFFC9FFFFFFBAZ FFFFFFC3
And the same after the fix
TX_WRITE len 4136, txg 1093817, seq 149231
foid 4242, offset 0, length f68
G 8E8791CC 1cAFC9BAZ C3
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#962
When replaying an unlink/remove operation via zfs_rmdir() the object
being removed will be instantiated by a call to zfs_dirent_lock().
This means that there is a single reference protecting the object.
Right before the call to zfs_inode_update() this reference is dropped
which may cause the object to be destroyed. This will result in a
NULL dereference as shown by the stack trace is issue #782.
This likely isn't an issue during normal operation because there is
always an additional reference held on the object by the VFS.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#782
Under certain circumstances the following functions may be called
in a context where KM_SLEEP is unsafe and can result in a deadlocked
system. To avoid this problem the unconditional KM_SLEEPs are
converted to KM_PUSHPAGEs. This will prevent them from attempting
to initiate any I/O during direct reclaim.
This change was originally part of cd5ca4b but was reverted by
330fe01. It always should have had its own commit for exactly
this reason.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
When the taskq code was originally written it seemed like a good
idea to simply map TQ_SLEEP to KM_SLEEP. Unfortunately, this
assumed that the TQ_* flags would never confict with any of the
Linux GFP_* flags. When adding the TQ_PUSHPAGE support in commit
cd5ca4b this invariant was accidentally broken.
Therefore to support TQ_PUSHPAGE, which is needed for Linux, and
prevent any further confusion I have removed this direct mapping.
The TQ_SLEEP, TQ_NOSLEEP, and TQ_PUSHPAGE are no longer defined
in terms of their KM_* counterparts. Instead a simple mapping
function is introduce to convert TQ_* -> KM_* where needed.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #171
This reverts commit cd5ca4b2f8
due to conflicts in the higher TQ_ bits which caused incorrect
behavior.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This reverts commit 395350c85d which
accidentally introduced issue #955.
Pools using AF drives which were originally created with a sector
size of 512 bytes will now be correctly detected to have physical
sector size of 4096. This is desirable for a new pool, however for
an existing pool abruptly changing the sector size causes problems.
For this reason, this change is being reverted until the additional
logic can be added to detect the existing pool case. Existing
pools must use the ashift size stored in the label regardless of
what the disk reports. This is critical for compatibility.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #955
Delay executing exportfs command until its results are actually
required.
Signed-off-by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Gunnar Beutner <gunnar@beutner.name>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
spl_config.h.in is a generated file: remove and .gitignore it
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
