Commit Graph

228 Commits

Author SHA1 Message Date
Brian Behlendorf 21fd04ec40 Linux 4.12 compat: CURRENT_TIME removed
Linux 4.9 added current_time() as the preferred interface to get
the filesystem time.  CURRENT_TIME was retired in Linux 4.12.

Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #6114
2017-06-09 14:05:15 -07:00
Brian Behlendorf e4cb6ee6a5 Linux 4.12 compat: super_setup_bdi_name()
All filesystems were converted to dynamically allocated BDIs.  The
destruction of backing_dev_info structures is handled as part of
super block destruction.  Refactor the code to abstract away the
details of creating and destroying a BDI.

Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #6089
2017-06-09 14:05:15 -07:00
Chunwei Chen 2094a93e87 Fix loop device becomes read-only
Commit 933ec99 removes read and write from f_op because the vfs layer will
select iter_write or aio_write automatically. However, for Linux <= 4.0,
loop_set_fd will actually check f_op->write and set read-only if not exists.
This patch add them back and use the generic do_sync_{read,write} for
aio_{read,write} and new_sync_{read,write} for {read,write}_iter.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #5776
Closes #5855
2017-06-09 14:05:15 -07:00
Olaf Faaland b4c181dc76 Linux 4.11 compat: iops.getattr and friends
In torvalds/linux@a528d35, there are changes to the getattr family of functions,
struct kstat, and the interface of inode_operations .getattr.

The inode_operations .getattr and simple_getattr() interface changed to:

int (*getattr) (const struct path *, struct dentry *, struct kstat *,
    u32 request_mask, unsigned int query_flags)

The request_mask argument indicates which field(s) the caller intends to use.
Fields the caller has not specified via request_mask may be set in the returned
struct anyway, but their values may be approximate.

The query_flags argument indicates whether the filesystem must update
the attributes from the backing store.

Currently both fields are ignored.  It is possible that getattr-related
functions within zfs could be optimized based on the request_mask.

struct kstat includes new fields:
u32               result_mask;  /* What fields the user got */
u64               attributes;   /* See STATX_ATTR_* flags */
struct timespec   btime;        /* File creation time */

Fields attribute and btime are cleared; the result_mask reflects this.  These
appear to be optional based on simple_getattr() and vfs_getattr() within the
kernel, which take the same approach.

Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes #5875
2017-06-09 14:05:15 -07:00
Chunwei Chen 5070e5311c Retire .write/.read file operations
The .write/.read file operations callbacks can be retired since
support for .read_iter/.write_iter and .aio_read/.aio_write has
been added.  The vfs_write()/vfs_read() entry functions will
select the correct interface for the kernel.  This is desirable
because all VFS write/read operations now rely on common code.

This change also add the generic write checks to make sure that
ulimits are enforced correctly on write.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #5587
Closes #5673
2017-02-03 10:25:37 -08:00
Gvozden Neskovic 9dd467a271 Fix ZFS_AC_KERNEL_SET_CACHED_ACL_USABLE check
Pass `ACL_TYPE_ACCESS` for type parameter of `set_cached_acl()` and
`forget_cached_acl()` to avoid removal of dead code after BUG() in
compile time. Tested on 3.2.0 kernel.

Introduced in 3779913

Reviewed-by: Massimo Maggi <me@massimo-maggi.eu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Closes #5378
2017-02-03 10:25:15 -08:00
Isaac Huang 6ebfe58117 Explicit block device plugging when submitting multiple BIOs
Without plugging, the default 'noop' scheduler will not merge
the BIOs which are part of a large ZIO.

Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Isaac Huang <he.huang@intel.com>
Closes #5181
2017-02-03 10:25:12 -08:00
Tim Chase 39d65926c9 4.10 compat - BIO flag changes and others
[bio] The req_op enum was changed to req_opf.  Update the "Linux 4.8 API"
autotools checks to use an int to determine whether the various REQ_OP
values are defined.  This should work properly on kernels >= 4.8.

[bio] bio_set_op_attrs() is now an inline function and can't be detected
with #ifdef.  Add a configure check to determine whether bio_set_op_attrs()
is defined.  Move the local definition of it from vdev_disk.c to
blkdev_compat.h for consistency with other related compability shims.

[bio] The read/write flags and their modifiers, including WRITE_FLUSH,
WRITE_FUA and WRITE_FLUSH_FUA have been removed from fs.h.  Add the new
bio_set_flush() compatibility wrapper to replace VDEV_WRITE_FLUSH_FUA
and set the flags appropriately for each supported kernel version.

[vfs] The generic_readlink() function has been made static.  If .readlink
in inode_operations is NULL, generic_readlink() is used.

[zol typo] Completely unrelated to 4.10 compat, fix a typo in the check
for REQ_OP_SECURE_ERASE so that the proper macro is defined:

    s/HAVE_REQ_OP_SECURE_DISCARD/HAVE_REQ_OP_SECURE_ERASE/

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #5499
2017-02-03 10:25:07 -08:00
Tim Chase 88fa992878 Fix sync behavior for disk vdevs
Prior to b39c22b, which was first generally available in the 0.6.5
release as b39c22b, ZoL never actually submitted synchronous read or write
requests to the Linux block layer.  This means the vdev_disk_dio_is_sync()
function had always returned false and, therefore, the completion in
dio_request_t.dr_comp was never actually used.

In b39c22b, synchronous ZIO operations were translated to synchronous
BIO requests in vdev_disk_io_start().  The follow-on commits 5592404 and
aa159af fixed several problems introduced by b39c22b.  In particular,
5592404 introduced the new flag parameter "wait" to __vdev_disk_physio()
but under ZoL, since vdev_disk_physio() is never actually used, the wait
flag was always zero so the new code had no effect other than to cause
a bug in the use of the dio_request_t.dr_comp which was fixed by aa159af.

The original rationale for introducing synchronous operations in b39c22b
was to hurry certains requests through the BIO layer which would have
otherwise been subject to its unplug timer which would increase the
latency.  This behavior of the unplug timer, however, went away during the
transition of the plug/unplug system between kernels 2.6.32 and 2.6.39.

To handle the unplug timer behavior on 2.6.32-2.6.35 kernels the
BIO_RW_UNPLUG flag is used as a hint to suppress the plugging behavior.

For kernels 2.6.36-2.6.38, the REQ_UNPLUG macro will be available and
ise used for the same purpose.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4858
2017-02-03 10:24:54 -08:00
Chunwei Chen c09af45f7b Use set_cached_acl and forget_cached_acl when possible
Originally, these two function are inline, so their usability is tied to
posix_acl_release. However, since Linux 3.14, they became EXPORT_SYMBOL, so we
can always use them. In this patch, we create an independent test for these
two functions so we can use them when possible.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
2017-02-03 10:24:50 -08:00
Hajo Möller ffcd0c5434 Fix lookup_bdev() on Ubuntu
Ubuntu added support for checking inode permissions to lookup_bdev() in kernel
commit 193fb6a2c94fab8eb8ce70a5da4d21c7d4023bee (merged in 4.4.0-6.21).
Upstream bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1636517

This patch adds a test for Ubuntu's variant of lookup_bdev() to configure and
calls the function in the correct way.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Hajo Möller <dasjoe@gmail.com>
Closes #5336
2017-02-03 10:24:34 -08:00
Brian Behlendorf cbf8713874 Use large stacks when available
While stack size will vary by architecture it has historically defaulted to
8K on x86_64 systems.  However, as of Linux 3.15 the default thread stack
size was increased to 16K.  These kernels are now the default in most non-
enterprise distributions which means we no longer need to assume 8K stacks.

This patch takes advantage of that fact by appropriately reverting stack
conservation changes which were made to ensure stability.  Changes which
may have had a negative impact on performance for certain workloads.  This
also has the side effect of bringing the code slightly more in line with
upstream.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Closes #4059
2017-02-03 10:24:22 -08:00
tuxoko 42dae6d7a6 Linux 3.14 compat: assign inode->set_acl
Linux 3.14 introduces inode->set_acl(). Normally, acl modification will come
from setxattr, which will handle by the acl xattr_handler, and we already
handles that well. However, nfsd will directly calls inode->set_acl or
return error if it doesn't exists.

Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed-by: Massimo Maggi <me@massimo-maggi.eu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #5371
Closes #5375
2017-02-03 10:24:09 -08:00
Brian Behlendorf f85c85ea06 Linux 4.9 compat: inode_change_ok() renamed setattr_prepare()
In torvalds/linux@31051c8 the inode_change_ok() function was
renamed setattr_prepare() and updated to take a dentry ratheri
than an inode.  Update the code to call the setattr_prepare()
and add a wrapper function which call inode_change_ok() for
older kernels.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
2017-02-03 10:24:06 -08:00
Chunwei Chen 670508f080 Linux 4.9 compat: remove iops->{set,get,remove}xattr
In Linux 4.9, torvalds/linux@fd50eca, iops->{set,get,remove}xattr and
generic_{set,get,remove}xattr are removed. xattr operations will directly
go through sb->s_xattr.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
2017-02-03 10:24:00 -08:00
Chunwei Chen 28172e8aa7 Linux 4.9 compat: iops->rename() wants flags
In Linux 4.9, torvalds/linux@2773bf0, iops->rename() and iops->rename2() are
merged together into iops->rename(), it now wants flags.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
2017-02-03 10:23:57 -08:00
DeHackEd dbc95a682c Kernel 4.9 compat: file_operations->aio_fsync removal
Linux kernel commit 723c038475b78 removed this field.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: DHE <git@dehacked.net>
Closes #5393
2017-02-03 10:23:50 -08:00
Brian Behlendorf bf8b4a9fd5 Linux 4.8 compat: Fix removal of bio->bi_rw member
All users of bio->bi_rw have been replaced with compatibility wrappers.
This allows the kernel specific logic to be abstracted away, and for
each of the supported cases to be documented with the wrapper.  The
updated interfaces are as follows:

* void blk_queue_set_write_cache(struct request_queue *, bool, bool)
* boolean_t bio_is_flush(struct bio *)
* boolean_t bio_is_fua(struct bio *)
* boolean_t bio_is_discard(struct bio *)
* boolean_t bio_is_secure_erase(struct bio *)
* VDEV_WRITE_FLUSH_FUA

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #4951
2016-09-09 13:21:10 -07:00
Brian Behlendorf 39a78fe9d4 Linux 4.8 compat: posix_acl_valid()
The posix_acl_valid() function has been updated to require a
user namespace.  Filesystem callers should normally provide the
user_ns from the super block associcated with the ACL; the
zpl_posix_acl_valid() wrapper has been added for this purpose.
See https://github.com/torvalds/linux/commit/0d4d717f for
complete details.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #4922
2016-09-09 13:21:10 -07:00
Brian Behlendorf 68b8d22c6e Linux 4.8 compat: submit_bio()
The rw argument has been removed from submit_bio/submit_bio_wait.
Callers are now expected to set bio->bi_rw instead of passing it
in.  See https://github.com/torvalds/linux/commit/4e49ea4a for
complete details.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4892
Issue #4899
2016-09-09 13:21:09 -07:00
Chunwei Chen 26e2bfa770 Linux 4.7 compat: fix zpl_get_acl returns invalid acl pointer
Starting from Linux 4.7, get_acl will set acl cache pointer to temporary
sentinel value before calling i_op->get_acl. Therefore we can't compare
against ACL_NOT_CACHED and return.

Since from Linux 3.14, get_acl already check the cache for us, so we
disable this in zpl_get_acl.

Linux 4.7 also does set_cached_acl for us so we disable it in zpl_get_acl.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4944
Closes #4946
2016-09-05 16:07:08 -07:00
Brian Behlendorf 97a1bbd4ea Retire HAVE_CURRENT_UMASK and HAVE_POSIX_ACL_CACHING
Remove ZFS_AC_KERNEL_CURRENT_UMASK and ZFS_AC_KERNEL_POSIX_ACL_CACHING
configure checks, all supported kernel provide this functionality.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #4922
2016-09-05 16:07:08 -07:00
Brian Behlendorf 01d9981349 Linux 4.7 compat: handler->set() takes both dentry and inode
Counterpart to fd4c7b7, the same approach was taken to resolve
the compatibility issue.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #4717
Issue #4665
2016-09-05 16:07:08 -07:00
Chunwei Chen 7043281906 Linux 4.7 compat: use iterate_shared for concurrent readdir
Register iterate_shared if it exists so the kernel will used shared
lock and allowing concurrent readdir.

Also, use shared lock when doing llseek with SEEK_DATA or SEEK_HOLE
to allow concurrent seeking.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4664
Closes #4665
2016-09-05 16:07:08 -07:00
Chunwei Chen 1aff4bb235 Linux 4.7 compat: replace blk_queue_flush with blk_queue_write_cache
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4665
2016-09-05 16:07:08 -07:00
Chunwei Chen 55b8857346 Linux 4.7 compat: handler->get() takes both dentry and inode
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4665
2016-09-05 16:07:08 -07:00
Chunwei Chen 31dbe4b404 Linux 4.5 compat: Use xattr_handler->name for acl
Linux 4.5 added member "name" to xattr_handler. xattr_handler which matches to
whole name rather than prefix should use "name" instead of "prefix".
Otherwise, kernel will return with EINVAL when it tries to resolve handlers.

Also, we remove the strcmp checks when xattr_handler has name, because
xattr_resolve_name will do the check for us.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4549
Closes #4537
2016-05-01 18:17:57 -04:00
Brian Behlendorf 9842008fc0 Linux 4.5 compat: xattr list handler
The registered xattr .list handler was simplified in the 4.5 kernel
to only perform a permission check.  Given a dentry for the file it
must return a boolean indicating if the name is visible.  This
differs slightly from the previous APIs which also required the
function to copy the name in to the provided list and return its
size.  That is now all the responsibility of the caller.

This should be straight forward change to make to ZoL since we've
always required the caller to make the copy.  However, this was
slightly complicated by the need to support 3 older APIs.  Yes,
between 2.6.32 and 4.5 there are 4 versions of this interface!

Therefore, while the functional change in this patch is small it
includes significant cleanup to make the code understandable and
maintainable.  These changes include:

- Improved configure checks for .list, .get, and .set interfaces.
  - Interfaces checked from newest to oldest.
  - Strict checking for each possible known interface.
  - Configure fails when no known interface is available.
  - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency
    with similar iops and fops configure checks.

- POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to
  move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}.
  Compatibility wrapper were added for old kernels.

- ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing
  ZPL_XATTR_{GET|SET} WRAPPERs.  Only the inode is guaranteed to be
  a valid pointer, passing NULL for the 'list' and 'name' variables
  is allowed and must be checked for.  All .list functions were
  updated to use the wrapper to aid readability.

- zpl_xattr_filldir() updated to use the .list function for its
  permission check which is consistent with the updated Linux 4.5
  interface.  If a .list function is registered it should return 0
  to indicate a name should be skipped, if there is no registered
  function the name will be added.

- Additional documentation from xattr(7) describing the correct
  behavior for each namespace was added before the relevant handlers.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Issue #4228
2016-01-29 09:52:13 -08:00
Brian Behlendorf b3c9e2caf5 Linux 4.5 compat: get_link() / put_link()
The follow_link() interface was retired in favor of get_link().
In the process of phasing in get_link() the Linux kernel went
through two different versions.  The first of which depended
on put_link() and the final version on a delayed done function.

- Improved configure checks for .follow_link, .get_link, .put_link.
  - Interfaces checked from newest to oldest.
  - Strict checking for each possible known interface.
  - Configure fails when no known interface is available.

- Both versions .get_link are detected and supported as well
  two previous versions of .follow_link.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Issue #4228
2016-01-29 09:52:13 -08:00
Kamil Domański 65d65b7a8d Skip GPL-only symbols test when cross-compiling
Signed-off-by: Kamil Domański <kamil@domanski.co>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4107
2015-12-23 17:29:34 -08:00
Chunwei Chen 15126e5d08 Linux 4.4 compat: xattr operations takes xattr_handler
The xattr_hander->{list,get,set} were changed to take a xattr_handler,
and handler_flags argument was removed and should be accessed by
handler->flags.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4021
2015-12-04 14:59:10 -08:00
Chunwei Chen e909a45d22 Linux 4.4 compat: make_request_fn returns blk_qc_t
As part of block polling support in Linux 4.4, make_request_fn should
return a cookie value of type blk_qc_t. For now, we make zvol_request
always return BLK_QC_T_NONE until we assess whether and how we want
to support block polling.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4021
2015-12-04 14:58:32 -08:00
Brian Behlendorf 057b87c00a Fix synchronous behavior in __vdev_disk_physio()
Commit b39c22b set the READ_SYNC and WRITE_SYNC flags for a bio
based on the ZIO_PRIORITY_* flag passed in.  This had the unnoticed
side-effect of making the vdev_disk_io_start() synchronous for
certain I/Os.

This in turn resulted in vdev_disk_io_start() being able to
re-dispatch zio's which would result in a RCU stalls when a disk
was removed from the system.  Additionally, this could negatively
impact performance and explains the performance regressions reported
in both #3829 and #3780.

This patch resolves the issue by making the blocking behavior
dependent on a 'wait' flag being passed rather than overloading
the passed bio flags.

Finally, the WRITE_SYNC and READ_SYNC behavior is restricted to
non-rotational devices where there is no benefit to queuing to
aggregate the I/O.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #3652
Issue #3780
Issue #3785
Issue #3817
Issue #3821
Issue #3829
Issue #3832
Issue #3870
2015-09-29 15:27:14 -07:00
Lukas Wunner c1013eb7ba Linux 4.3 compat: bio_end_io_t / BIO_UPTODATE
Commit torvalds/linux@4246a0b63b
("block: add a bi_error field to struct bio") dropped the error
argument from bio_endio in favor of newly introduced bio->bi_error.
This also replaces bio->bi_flags value BIO_UPTODATE.

bio_endio was a 3 argument function until Linux 2.6.24, which made it
a 2 argument function, and now the prototype has changed yet again to
a 1 argument function. Support for pre 2.6.24 kernels was already
dropped with 37f9dac592 ("zvol processing should use struct bio")
which assumed the 2 argument version in zvol_request(). Remaining code
to support the 3 argument version is hereby removed.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Issue #3799
2015-09-29 15:27:14 -07:00
Richard Yao 8198d18ca7 Reintroduce IO accounting on zvols on Linux 3.19+
zfsonlinux/zfs@e20cd6f7a8 caused us to
lose IO accounting on zvols. When I originally wrote that last year, the
symbols we needed to maintain IO accounting were GPL exported, but
torvalds/linux@394ffa503b provided
suitable symbols for restoring this functionality 4 months later.  We
can call them to restore the IO accounting on Linux 3.19 and later as
well as any older kernels where that patch is backported.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3741
2015-09-09 09:29:24 -07:00
Richard Yao d60328645d Remove blk_queue_nonrot() autotools check
This autotools check was never needed because we can check for the
existence of QUEUE_FLAG_NONROT in the kernel headers.

Also, the comment in config/kernel-blk-queue-nonrot.m4 is incorrect.
This was a Linux 2.6.28 API change, not a Linux 2.6.27 API change.

Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:25 -04:00
Richard Yao d677203a9b Remove blk_queue_discard() autotools check
This autotools check was never needed because we can check for the
existence of QUEUE_FLAG_DISCARD in the kernel headers.

Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:25 -04:00
Richard Yao 7d6e2adb4e Remove blk_rq_bytes()/blk_rq_sectors autotools checks
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao f952eaa7ec Remove blk_rq_pos() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao f8c56b405d Remove blk_fetch_request() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao e8c6be131c Remove blk_requeue_request() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao dd6f9fe61b Remove blk_end_request() autotools check.
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 65f340e725 Remove rq_is_sync() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 9ddf9b8e15 Remove rq_for_each_segment() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 37f9dac592 zvol processing should use struct bio
Internally, zvols are files exposed through the block device API. This
is intended to reduce overhead when things require block devices.
However, the ZoL zvol code emulates a traditional block device in that
it has a top half and a bottom half. This is an unnecessary source of
overhead that does not exist on any other OpenZFS platform does this.
This patch removes it. Early users of this patch reported double digit
performance gains in IOPS on zvols in the range of 50% to 80%.

Comments in the code suggest that the current implementation was done to
obtain IO merging from Linux's IO elevator. However, the DMU already
does write merging while arc_read() should implicitly merge read IOs
because only 1 thread is permitted to fetch the buffer into ARC. In
addition, commercial ZFSOnLinux distributions report that regular files
are more performant than zvols under the current implementation, and the
main consumers of zvols are VMs and iSCSI targets, which have their own
elevators to merge IOs.

Some minor refactoring allows us to register zfs_request() as our
->make_request() handler in place of the generic_make_request()
function. This eliminates the layer of code that broke IO requests on
zvols into a top half and a bottom half. This has several benefits:

1. No per zvol spinlocks.
2. No redundant IO elevator processing.
3. Interrupts are disabled only when actually necessary.
4. No redispatching of IOs when all taskq threads are busy.
5. Linux's page out routines will properly block.
6. Many autotools checks become obsolete.

An unfortunate consequence of eliminating the layer that
generic_make_request() is that we no longer calls the instrumentation
hooks for block IO accounting. Those hooks are GPL-exported, so we
cannot call them ourselves and consequently, we lose the ability to do
IO monitoring via iostat.  Since zvols are internally files mapped as
block devices, this should be okay. Anyone who is willing to accept the
performance penalty for the block IO layer's accounting could use the
loop device in between the zvol and its consumer. Alternatively, perf
and ftrace likely could be used. Also, tools like latencytop will still
work. Tools such as latencytop sometimes provide a better view of
performance bottlenecks than the traditional block IO accounting tools
do.

Lastly, if direct reclaim occurs during spacemap loading and swap is on
a zvol, this code will deadlock. That deadlock could already occur with
sync=always on zvols. Given that swap on zvols is not yet production
ready, this is not a blocker.

Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:30:24 -04:00
Richard Yao 97771edaca Remove blk_queue_io_opt() autotools check
This is needed for supporting kernels earlier than 2.6.30. Support for
those kernels was dropped, so we can safely remove this check.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-09-01 09:33:18 -07:00
Richard Yao 3c119330a6 Remove blk_queue_physical_block_size() autotools check
This is needed for supporting kernels earlier than 2.6.30. Support for
those kernels was dropped, so we can safely remove this check.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-09-01 09:33:18 -07:00
Brian Behlendorf 278bee9319 Linux 3.18 compat: Snapshot auto-mounting
Re-factor the .zfs/snapshot auto-mouting code to take in to account
changes made to the upstream kernels.  And to lay the groundwork for
enabling access to .zfs snapshots via NFS clients.  This patch makes
the following core improvements.

* All actively auto-mounted snapshots are now tracked in two global
trees which are indexed by snapshot name and objset id respectively.
This allows for fast lookups of any auto-mounted snapshot regardless
without needing access to the parent dataset.

* Snapshot entries are added to the tree in zfsctl_snapshot_mount().
However, they are now removed from the tree in the context of the
unmount process.  This eliminates the need complicated error logic
in zfsctl_snapshot_unmount() to handle unmount failures.

* References are now taken on the snapshot entries in the tree to
ensure they always remain valid while a task is outstanding.

* The MNT_SHRINKABLE flag is set on the snapshot vfsmount_t right
after the auto-mount succeeds.  This allows to kernel to unmount
idle auto-mounted snapshots if needed removing the need for the
zfsctl_unmount_snapshots() function.

* Snapshots in active use will not be automatically unmounted.  As
long as at least one dentry is revalidated every zfs_expire_snapshot/2
seconds the auto-unmount expiration timer will be extended.

* Commit torvalds/linux@bafc9b7 caused snapshots auto-mounted by ZFS
to be immediately unmounted when the dentry was revalidated.  This
was a consequence of ZFS invaliding all snapdir dentries to ensure that
negative dentries didn't mask new snapshots.  This patch modifies the
behavior such that only negative dentries are invalidated.  This solves
the issue and may result in a performance improvement.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3589
Closes #3344
Closes #3295
Closes #3257
Closes #3243
Closes #3030
Closes #2841
2015-08-31 13:54:39 -07:00
Chunwei Chen 17888ae30d Add compatibility layer for {kmap,kunmap}_atomic
Starting from linux-2.6.37, {kmap,kunmap}_atomic takes 1 argument instead of 2.
We use zfs_{kmap,kunmap}_atomic as wrappers and always take 2 argument, but
ignore the 2nd for newer kernel.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-08-24 10:13:25 -07:00
Chris Dunlop 302f31ffc7 Linux 4.1 compat: configure bdi_setup_and_register()
Pull struct backing_dev_info off the stack: by linux-4.1 it's grown
past our 1024 byte stack frame warning limit resulting in an incorrect
configure result.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Closes #3671
2015-08-18 16:43:04 -07:00