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
This commit is contained in:
Tim Chase 2016-12-30 16:03:59 -06:00 committed by Brian Behlendorf
parent 3500a14595
commit a5e046eaac
6 changed files with 97 additions and 20 deletions

View File

@ -10,7 +10,7 @@ AC_DEFUN([ZFS_AC_KERNEL_REQ_OP_DISCARD], [
ZFS_LINUX_TRY_COMPILE([
#include <linux/blk_types.h>
],[
enum req_op op __attribute__ ((unused)) = REQ_OP_DISCARD;
int op __attribute__ ((unused)) = REQ_OP_DISCARD;
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_REQ_OP_DISCARD, 1,
@ -25,10 +25,10 @@ AC_DEFUN([ZFS_AC_KERNEL_REQ_OP_SECURE_ERASE], [
ZFS_LINUX_TRY_COMPILE([
#include <linux/blk_types.h>
],[
enum req_op op __attribute__ ((unused)) = REQ_OP_SECURE_ERASE;
int op __attribute__ ((unused)) = REQ_OP_SECURE_ERASE;
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_REQ_OP_SECURE_DISCARD, 1,
AC_DEFINE(HAVE_REQ_OP_SECURE_ERASE, 1,
[REQ_OP_SECURE_ERASE is defined])
],[
AC_MSG_RESULT(no)
@ -41,7 +41,7 @@ AC_DEFUN([ZFS_AC_KERNEL_REQ_OP_FLUSH], [
ZFS_LINUX_TRY_COMPILE([
#include <linux/blk_types.h>
],[
enum req_op op __attribute__ ((unused)) = REQ_OP_FLUSH;
int op __attribute__ ((unused)) = REQ_OP_FLUSH;
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_REQ_OP_FLUSH, 1,
@ -65,3 +65,20 @@ AC_DEFUN([ZFS_AC_KERNEL_BIO_BI_OPF], [
AC_MSG_RESULT(no)
])
])
AC_DEFUN([ZFS_AC_KERNEL_HAVE_BIO_SET_OP_ATTRS], [
AC_MSG_CHECKING([whether bio_set_op_attrs is available])
ZFS_LINUX_TRY_COMPILE([
#include <linux/blk_types.h>
],[
struct bio *bio __attribute__ ((unused)) = NULL;
bio_set_op_attrs(bio, 0, 0);
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_BIO_SET_OP_ATTRS, 1,
[bio_set_op_attrs is available])
],[
AC_MSG_RESULT(no)
])
])

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@ -0,0 +1,22 @@
dnl #
dnl # 4.10 API
dnl #
dnl # NULL inode_operations.readlink implies generic_readlink(), which
dnl # has been made static.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_GENERIC_READLINK_GLOBAL], [
AC_MSG_CHECKING([whether generic_readlink is global])
ZFS_LINUX_TRY_COMPILE([
#include <linux/fs.h>
],[
int i __attribute__ ((unused));
i = generic_readlink(NULL, NULL, 0);
],[
AC_MSG_RESULT([yes])
AC_DEFINE(HAVE_GENERIC_READLINK, 1,
[generic_readlink is global])
],[
AC_MSG_RESULT([no])
])
])

View File

@ -37,6 +37,8 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
ZFS_AC_KERNEL_BLK_QUEUE_HAVE_BLK_PLUG
ZFS_AC_KERNEL_GET_DISK_RO
ZFS_AC_KERNEL_GET_GENDISK
ZFS_AC_KERNEL_HAVE_BIO_SET_OP_ATTRS
ZFS_AC_KERNEL_GENERIC_READLINK_GLOBAL
ZFS_AC_KERNEL_DISCARD_GRANULARITY
ZFS_AC_KERNEL_CONST_XATTR_HANDLER
ZFS_AC_KERNEL_XATTR_HANDLER_NAME

View File

@ -303,20 +303,59 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
#endif /* HAVE_BDEV_LOGICAL_BLOCK_SIZE */
#endif /* HAVE_BDEV_PHYSICAL_BLOCK_SIZE */
#ifndef HAVE_BIO_SET_OP_ATTRS
/*
* 2.6.37 API change
* The WRITE_FLUSH, WRITE_FUA, and WRITE_FLUSH_FUA flags have been
* introduced as a replacement for WRITE_BARRIER. This was done to
* allow richer semantics to be expressed to the block layer. It is
* the block layers responsibility to choose the correct way to
* implement these semantics.
* Kernels without bio_set_op_attrs use bi_rw for the bio flags.
*/
#ifdef WRITE_FLUSH_FUA
#define VDEV_WRITE_FLUSH_FUA WRITE_FLUSH_FUA
#else
#define VDEV_WRITE_FLUSH_FUA WRITE_BARRIER
static inline void
bio_set_op_attrs(struct bio *bio, unsigned rw, unsigned flags)
{
bio->bi_rw |= rw | flags;
}
#endif
/*
* bio_set_flush - Set the appropriate flags in a bio to guarantee
* data are on non-volatile media on completion.
*
* 2.6.X - 2.6.36 API,
* WRITE_BARRIER - Tells the block layer to commit all previously submitted
* writes to stable storage before this one is started and that the current
* write is on stable storage upon completion. Also prevents reordering
* on both sides of the current operation.
*
* 2.6.37 - 4.8 API,
* Introduce WRITE_FLUSH, WRITE_FUA, and WRITE_FLUSH_FUA flags as a
* replacement for WRITE_BARRIER to allow expressing richer semantics
* to the block layer. It's up to the block layer to implement the
* semantics correctly. Use the WRITE_FLUSH_FUA flag combination.
*
* 4.8 - 4.9 API,
* REQ_FLUSH was renamed to REQ_PREFLUSH. For consistency with previous
* ZoL releases, prefer the WRITE_FLUSH_FUA flag set if it's available.
*
* 4.10 API,
* The read/write flags and their modifiers, including WRITE_FLUSH,
* WRITE_FUA and WRITE_FLUSH_FUA were removed from fs.h in
* torvalds/linux@70fd7614 and replaced by direct flag modification
* of the REQ_ flags in bio->bi_opf. Use REQ_PREFLUSH.
*/
static inline void
bio_set_flush(struct bio *bio)
{
#if defined(WRITE_BARRIER) /* < 2.6.37 */
bio_set_op_attrs(bio, 0, WRITE_BARRIER);
#elif defined(WRITE_FLUSH_FUA) /* >= 2.6.37 and <= 4.9 */
bio_set_op_attrs(bio, 0, WRITE_FLUSH_FUA);
#elif defined(REQ_PREFLUSH) /* >= 4.10 */
bio_set_op_attrs(bio, 0, REQ_PREFLUSH);
#else
#error "Allowing the build will cause bio_set_flush requests to be ignored."
"Please file an issue report at: "
"https://github.com/zfsonlinux/zfs/issues/new"
#endif
}
/*
* 4.8 - 4.x API,
* REQ_OP_FLUSH

View File

@ -488,11 +488,6 @@ bio_map_abd_off(struct bio *bio, abd_t *abd, unsigned int size, size_t off)
return (abd_scatter_bio_map_off(bio, abd, size, off));
}
#ifndef bio_set_op_attrs
#define bio_set_op_attrs(bio, rw, flags) \
do { (bio)->bi_rw |= (rw)|(flags); } while (0)
#endif
static inline void
vdev_submit_bio_impl(struct bio *bio)
{
@ -659,7 +654,7 @@ vdev_disk_io_flush(struct block_device *bdev, zio_t *zio)
bio->bi_end_io = vdev_disk_io_flush_completion;
bio->bi_private = zio;
bio->bi_bdev = bdev;
bio_set_op_attrs(bio, 0, VDEV_WRITE_FLUSH_FUA);
bio_set_flush(bio);
vdev_submit_bio(bio);
invalidate_bdev(bdev);

View File

@ -770,7 +770,9 @@ const struct inode_operations zpl_dir_inode_operations = {
};
const struct inode_operations zpl_symlink_inode_operations = {
#ifdef HAVE_GENERIC_READLINK
.readlink = generic_readlink,
#endif
#if defined(HAVE_GET_LINK_DELAYED) || defined(HAVE_GET_LINK_COOKIE)
.get_link = zpl_get_link,
#elif defined(HAVE_FOLLOW_LINK_COOKIE) || defined(HAVE_FOLLOW_LINK_NAMEIDATA)