Allow manual discards from userspace using the FITRIM ioctl.  This is not
intended to be run during normal workloads, as the freepsace btree walks
can cause large performance degradation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
This commit is contained in:
Christoph Hellwig 2011-01-07 13:02:04 +00:00 коммит произвёл Alex Elder
Родитель c58efdb442
Коммит a46db60834
7 изменённых файлов: 259 добавлений и 12 удалений

Просмотреть файл

@ -98,6 +98,7 @@ xfs-y += $(addprefix $(XFS_LINUX)/, \
kmem.o \
xfs_aops.o \
xfs_buf.o \
xfs_discard.o \
xfs_export.o \
xfs_file.o \
xfs_fs_subr.o \

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@ -0,0 +1,191 @@
/*
* Copyright (C) 2010 Red Hat, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_sb.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_quota.h"
#include "xfs_trans.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_inode.h"
#include "xfs_alloc.h"
#include "xfs_error.h"
#include "xfs_discard.h"
#include "xfs_trace.h"
STATIC int
xfs_trim_extents(
struct xfs_mount *mp,
xfs_agnumber_t agno,
xfs_fsblock_t start,
xfs_fsblock_t len,
xfs_fsblock_t minlen,
__uint64_t *blocks_trimmed)
{
struct block_device *bdev = mp->m_ddev_targp->bt_bdev;
struct xfs_btree_cur *cur;
struct xfs_buf *agbp;
struct xfs_perag *pag;
int error;
int i;
pag = xfs_perag_get(mp, agno);
error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agbp);
if (error || !agbp)
goto out_put_perag;
cur = xfs_allocbt_init_cursor(mp, NULL, agbp, agno, XFS_BTNUM_CNT);
/*
* Force out the log. This means any transactions that might have freed
* space before we took the AGF buffer lock are now on disk, and the
* volatile disk cache is flushed.
*/
xfs_log_force(mp, XFS_LOG_SYNC);
/*
* Look up the longest btree in the AGF and start with it.
*/
error = xfs_alloc_lookup_le(cur, 0,
XFS_BUF_TO_AGF(agbp)->agf_longest, &i);
if (error)
goto out_del_cursor;
/*
* Loop until we are done with all extents that are large
* enough to be worth discarding.
*/
while (i) {
xfs_agblock_t fbno;
xfs_extlen_t flen;
error = xfs_alloc_get_rec(cur, &fbno, &flen, &i);
if (error)
goto out_del_cursor;
XFS_WANT_CORRUPTED_GOTO(i == 1, out_del_cursor);
ASSERT(flen <= XFS_BUF_TO_AGF(agbp)->agf_longest);
/*
* Too small? Give up.
*/
if (flen < minlen) {
trace_xfs_discard_toosmall(mp, agno, fbno, flen);
goto out_del_cursor;
}
/*
* If the extent is entirely outside of the range we are
* supposed to discard skip it. Do not bother to trim
* down partially overlapping ranges for now.
*/
if (XFS_AGB_TO_FSB(mp, agno, fbno) + flen < start ||
XFS_AGB_TO_FSB(mp, agno, fbno) >= start + len) {
trace_xfs_discard_exclude(mp, agno, fbno, flen);
goto next_extent;
}
/*
* If any blocks in the range are still busy, skip the
* discard and try again the next time.
*/
if (xfs_alloc_busy_search(mp, agno, fbno, flen)) {
trace_xfs_discard_busy(mp, agno, fbno, flen);
goto next_extent;
}
trace_xfs_discard_extent(mp, agno, fbno, flen);
error = -blkdev_issue_discard(bdev,
XFS_AGB_TO_DADDR(mp, agno, fbno),
XFS_FSB_TO_BB(mp, flen),
GFP_NOFS, 0);
if (error)
goto out_del_cursor;
*blocks_trimmed += flen;
next_extent:
error = xfs_btree_decrement(cur, 0, &i);
if (error)
goto out_del_cursor;
}
out_del_cursor:
xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
xfs_buf_relse(agbp);
out_put_perag:
xfs_perag_put(pag);
return error;
}
int
xfs_ioc_trim(
struct xfs_mount *mp,
struct fstrim_range __user *urange)
{
struct request_queue *q = mp->m_ddev_targp->bt_bdev->bd_disk->queue;
unsigned int granularity = q->limits.discard_granularity;
struct fstrim_range range;
xfs_fsblock_t start, len, minlen;
xfs_agnumber_t start_agno, end_agno, agno;
__uint64_t blocks_trimmed = 0;
int error, last_error = 0;
if (!capable(CAP_SYS_ADMIN))
return -XFS_ERROR(EPERM);
if (copy_from_user(&range, urange, sizeof(range)))
return -XFS_ERROR(EFAULT);
/*
* Truncating down the len isn't actually quite correct, but using
* XFS_B_TO_FSB would mean we trivially get overflows for values
* of ULLONG_MAX or slightly lower. And ULLONG_MAX is the default
* used by the fstrim application. In the end it really doesn't
* matter as trimming blocks is an advisory interface.
*/
start = XFS_B_TO_FSBT(mp, range.start);
len = XFS_B_TO_FSBT(mp, range.len);
minlen = XFS_B_TO_FSB(mp, max_t(u64, granularity, range.minlen));
start_agno = XFS_FSB_TO_AGNO(mp, start);
if (start_agno >= mp->m_sb.sb_agcount)
return -XFS_ERROR(EINVAL);
end_agno = XFS_FSB_TO_AGNO(mp, start + len);
if (end_agno >= mp->m_sb.sb_agcount)
end_agno = mp->m_sb.sb_agcount - 1;
for (agno = start_agno; agno <= end_agno; agno++) {
error = -xfs_trim_extents(mp, agno, start, len, minlen,
&blocks_trimmed);
if (error)
last_error = error;
}
if (last_error)
return last_error;
range.len = XFS_FSB_TO_B(mp, blocks_trimmed);
if (copy_to_user(urange, &range, sizeof(range)))
return -XFS_ERROR(EFAULT);
return 0;
}

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@ -0,0 +1,8 @@
#ifndef XFS_DISCARD_H
#define XFS_DISCARD_H 1
struct fstrim_range;
extern int xfs_ioc_trim(struct xfs_mount *, struct fstrim_range __user *);
#endif /* XFS_DISCARD_H */

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@ -39,6 +39,7 @@
#include "xfs_dfrag.h"
#include "xfs_fsops.h"
#include "xfs_vnodeops.h"
#include "xfs_discard.h"
#include "xfs_quota.h"
#include "xfs_inode_item.h"
#include "xfs_export.h"
@ -1294,6 +1295,8 @@ xfs_file_ioctl(
trace_xfs_file_ioctl(ip);
switch (cmd) {
case FITRIM:
return xfs_ioc_trim(mp, arg);
case XFS_IOC_ALLOCSP:
case XFS_IOC_FREESP:
case XFS_IOC_RESVSP:

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@ -1759,6 +1759,39 @@ DEFINE_LOG_RECOVER_INO_ITEM(xfs_log_recover_inode_recover);
DEFINE_LOG_RECOVER_INO_ITEM(xfs_log_recover_inode_cancel);
DEFINE_LOG_RECOVER_INO_ITEM(xfs_log_recover_inode_skip);
DECLARE_EVENT_CLASS(xfs_discard_class,
TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno,
xfs_agblock_t agbno, xfs_extlen_t len),
TP_ARGS(mp, agno, agbno, len),
TP_STRUCT__entry(
__field(dev_t, dev)
__field(xfs_agnumber_t, agno)
__field(xfs_agblock_t, agbno)
__field(xfs_extlen_t, len)
),
TP_fast_assign(
__entry->dev = mp->m_super->s_dev;
__entry->agno = agno;
__entry->agbno = agbno;
__entry->len = len;
),
TP_printk("dev %d:%d agno %u agbno %u len %u\n",
MAJOR(__entry->dev), MINOR(__entry->dev),
__entry->agno,
__entry->agbno,
__entry->len)
)
#define DEFINE_DISCARD_EVENT(name) \
DEFINE_EVENT(xfs_discard_class, name, \
TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno, \
xfs_agblock_t agbno, xfs_extlen_t len), \
TP_ARGS(mp, agno, agbno, len))
DEFINE_DISCARD_EVENT(xfs_discard_extent);
DEFINE_DISCARD_EVENT(xfs_discard_toosmall);
DEFINE_DISCARD_EVENT(xfs_discard_exclude);
DEFINE_DISCARD_EVENT(xfs_discard_busy);
#endif /* _TRACE_XFS_H */
#undef TRACE_INCLUDE_PATH

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@ -41,10 +41,6 @@
#define XFSA_FIXUP_BNO_OK 1
#define XFSA_FIXUP_CNT_OK 2
static int
xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
xfs_agblock_t bno, xfs_extlen_t len);
/*
* Prototypes for per-ag allocation routines
*/
@ -94,7 +90,7 @@ xfs_alloc_lookup_ge(
* Lookup the first record less than or equal to [bno, len]
* in the btree given by cur.
*/
STATIC int /* error */
int /* error */
xfs_alloc_lookup_le(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
@ -127,7 +123,7 @@ xfs_alloc_update(
/*
* Get the data from the pointed-to record.
*/
STATIC int /* error */
int /* error */
xfs_alloc_get_rec(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t *bno, /* output: starting block of extent */
@ -2615,7 +2611,7 @@ restart:
* will require a synchronous transaction, but it can still be
* used to distinguish between a partial or exact match.
*/
static int
int
xfs_alloc_busy_search(
struct xfs_mount *mp,
xfs_agnumber_t agno,

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@ -19,6 +19,7 @@
#define __XFS_ALLOC_H__
struct xfs_buf;
struct xfs_btree_cur;
struct xfs_mount;
struct xfs_perag;
struct xfs_trans;
@ -118,16 +119,16 @@ xfs_alloc_longest_free_extent(struct xfs_mount *mp,
struct xfs_perag *pag);
#ifdef __KERNEL__
void
xfs_alloc_busy_insert(xfs_trans_t *tp,
xfs_agnumber_t agno,
xfs_agblock_t bno,
xfs_extlen_t len);
xfs_alloc_busy_insert(struct xfs_trans *tp, xfs_agnumber_t agno,
xfs_agblock_t bno, xfs_extlen_t len);
void
xfs_alloc_busy_clear(struct xfs_mount *mp, struct xfs_busy_extent *busyp);
int
xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
xfs_agblock_t bno, xfs_extlen_t len);
#endif /* __KERNEL__ */
/*
@ -205,4 +206,18 @@ xfs_free_extent(
xfs_fsblock_t bno, /* starting block number of extent */
xfs_extlen_t len); /* length of extent */
int /* error */
xfs_alloc_lookup_le(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat); /* success/failure */
int /* error */
xfs_alloc_get_rec(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t *bno, /* output: starting block of extent */
xfs_extlen_t *len, /* output: length of extent */
int *stat); /* output: success/failure */
#endif /* __XFS_ALLOC_H__ */