diff --git a/Documentation/filesystems/xfs.txt b/Documentation/filesystems/xfs.txt
index 7bff3e4f35df84a9def7507badb42ccdeffef419..3fc0c31a6f5dc5f8ee1220d9bcf8062038297aa5 100644
--- a/Documentation/filesystems/xfs.txt
+++ b/Documentation/filesystems/xfs.txt
@@ -39,6 +39,12 @@ When mounting an XFS filesystem, the following options are accepted.
drive level write caching to be enabled, for devices that
support write barriers.
+ discard
+ Issue command to let the block device reclaim space freed by the
+ filesystem. This is useful for SSD devices, thinly provisioned
+ LUNs and virtual machine images, but may have a performance
+ impact. This option is incompatible with the nodelaylog option.
+
dmapi
Enable the DMAPI (Data Management API) event callouts.
Use with the "mtpt" option.
diff --git a/fs/xfs/linux-2.6/xfs_discard.c b/fs/xfs/linux-2.6/xfs_discard.c
index d61611c88012c8daaab1840f9534983fac62bd2d..244e797dae327a7da95992e23697489397c4bbc1 100644
--- a/fs/xfs/linux-2.6/xfs_discard.c
+++ b/fs/xfs/linux-2.6/xfs_discard.c
@@ -191,3 +191,32 @@ xfs_ioc_trim(
return -XFS_ERROR(EFAULT);
return 0;
}
+
+int
+xfs_discard_extents(
+ struct xfs_mount *mp,
+ struct list_head *list)
+{
+ struct xfs_busy_extent *busyp;
+ int error = 0;
+
+ list_for_each_entry(busyp, list, list) {
+ trace_xfs_discard_extent(mp, busyp->agno, busyp->bno,
+ busyp->length);
+
+ error = -blkdev_issue_discard(mp->m_ddev_targp->bt_bdev,
+ XFS_AGB_TO_DADDR(mp, busyp->agno, busyp->bno),
+ XFS_FSB_TO_BB(mp, busyp->length),
+ GFP_NOFS, 0);
+ if (error && error != EOPNOTSUPP) {
+ xfs_info(mp,
+ "discard failed for extent [0x%llu,%u], error %d",
+ (unsigned long long)busyp->bno,
+ busyp->length,
+ error);
+ return error;
+ }
+ }
+
+ return 0;
+}
diff --git a/fs/xfs/linux-2.6/xfs_discard.h b/fs/xfs/linux-2.6/xfs_discard.h
index e82b6dd3e127707ed0a8e154ab1617da23444a90..344879aea646cfbaf3ac1c57916f9fce5e6a50c2 100644
--- a/fs/xfs/linux-2.6/xfs_discard.h
+++ b/fs/xfs/linux-2.6/xfs_discard.h
@@ -2,7 +2,9 @@
#define XFS_DISCARD_H 1
struct fstrim_range;
+struct list_head;
extern int xfs_ioc_trim(struct xfs_mount *, struct fstrim_range __user *);
+extern int xfs_discard_extents(struct xfs_mount *, struct list_head *);
#endif /* XFS_DISCARD_H */
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index b0aa59e51fd066377d29f92da999dff54b1a1620..98b9c91fcdf1d9d101339aadaea2740e74cb6506 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -110,8 +110,10 @@ mempool_t *xfs_ioend_pool;
#define MNTOPT_GQUOTANOENF "gqnoenforce"/* group quota limit enforcement */
#define MNTOPT_PQUOTANOENF "pqnoenforce"/* project quota limit enforcement */
#define MNTOPT_QUOTANOENF "qnoenforce" /* same as uqnoenforce */
-#define MNTOPT_DELAYLOG "delaylog" /* Delayed loging enabled */
-#define MNTOPT_NODELAYLOG "nodelaylog" /* Delayed loging disabled */
+#define MNTOPT_DELAYLOG "delaylog" /* Delayed logging enabled */
+#define MNTOPT_NODELAYLOG "nodelaylog" /* Delayed logging disabled */
+#define MNTOPT_DISCARD "discard" /* Discard unused blocks */
+#define MNTOPT_NODISCARD "nodiscard" /* Do not discard unused blocks */
/*
* Table driven mount option parser.
@@ -355,6 +357,10 @@ xfs_parseargs(
mp->m_flags |= XFS_MOUNT_DELAYLOG;
} else if (!strcmp(this_char, MNTOPT_NODELAYLOG)) {
mp->m_flags &= ~XFS_MOUNT_DELAYLOG;
+ } else if (!strcmp(this_char, MNTOPT_DISCARD)) {
+ mp->m_flags |= XFS_MOUNT_DISCARD;
+ } else if (!strcmp(this_char, MNTOPT_NODISCARD)) {
+ mp->m_flags &= ~XFS_MOUNT_DISCARD;
} else if (!strcmp(this_char, "ihashsize")) {
xfs_warn(mp,
"ihashsize no longer used, option is deprecated.");
@@ -388,6 +394,13 @@ xfs_parseargs(
return EINVAL;
}
+ if ((mp->m_flags & XFS_MOUNT_DISCARD) &&
+ !(mp->m_flags & XFS_MOUNT_DELAYLOG)) {
+ xfs_warn(mp,
+ "the discard option is incompatible with the nodelaylog option");
+ return EINVAL;
+ }
+
#ifndef CONFIG_XFS_QUOTA
if (XFS_IS_QUOTA_RUNNING(mp)) {
xfs_warn(mp, "quota support not available in this kernel.");
@@ -488,6 +501,7 @@ xfs_showargs(
{ XFS_MOUNT_FILESTREAMS, "," MNTOPT_FILESTREAM },
{ XFS_MOUNT_GRPID, "," MNTOPT_GRPID },
{ XFS_MOUNT_DELAYLOG, "," MNTOPT_DELAYLOG },
+ { XFS_MOUNT_DISCARD, "," MNTOPT_DISCARD },
{ 0, NULL }
};
static struct proc_xfs_info xfs_info_unset[] = {
diff --git a/fs/xfs/xfs_ag.h b/fs/xfs/xfs_ag.h
index da0a561ffba2abc2ed277992f21f44c1a38dbc54..8d52ba4c87e54314f5106bd19bc92a3626a3f2da 100644
--- a/fs/xfs/xfs_ag.h
+++ b/fs/xfs/xfs_ag.h
@@ -187,6 +187,8 @@ struct xfs_busy_extent {
xfs_agnumber_t agno;
xfs_agblock_t bno;
xfs_extlen_t length;
+ unsigned int flags;
+#define XFS_ALLOC_BUSY_DISCARDED 0x01 /* undergoing a discard op. */
};
/*
diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index acdced86413ce0d90e5fb07ac7ea08005727a2e4..721db22c6ec9e29bd4448d01eb6c0caf2486bb3e 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -2608,6 +2608,18 @@ xfs_alloc_busy_update_extent(
xfs_agblock_t bbno = busyp->bno;
xfs_agblock_t bend = bbno + busyp->length;
+ /*
+ * This extent is currently being discarded. Give the thread
+ * performing the discard a chance to mark the extent unbusy
+ * and retry.
+ */
+ if (busyp->flags & XFS_ALLOC_BUSY_DISCARDED) {
+ spin_unlock(&pag->pagb_lock);
+ delay(1);
+ spin_lock(&pag->pagb_lock);
+ return false;
+ }
+
/*
* If there is a busy extent overlapping a user allocation, we have
* no choice but to force the log and retry the search.
@@ -2813,7 +2825,8 @@ restart:
* If this is a metadata allocation, try to reuse the busy
* extent instead of trimming the allocation.
*/
- if (!args->userdata) {
+ if (!args->userdata &&
+ !(busyp->flags & XFS_ALLOC_BUSY_DISCARDED)) {
if (!xfs_alloc_busy_update_extent(args->mp, args->pag,
busyp, fbno, flen,
false))
@@ -2979,10 +2992,16 @@ xfs_alloc_busy_clear_one(
kmem_free(busyp);
}
+/*
+ * Remove all extents on the passed in list from the busy extents tree.
+ * If do_discard is set skip extents that need to be discarded, and mark
+ * these as undergoing a discard operation instead.
+ */
void
xfs_alloc_busy_clear(
struct xfs_mount *mp,
- struct list_head *list)
+ struct list_head *list,
+ bool do_discard)
{
struct xfs_busy_extent *busyp, *n;
struct xfs_perag *pag = NULL;
@@ -2999,7 +3018,10 @@ xfs_alloc_busy_clear(
agno = busyp->agno;
}
- xfs_alloc_busy_clear_one(mp, pag, busyp);
+ if (do_discard && busyp->length)
+ busyp->flags = XFS_ALLOC_BUSY_DISCARDED;
+ else
+ xfs_alloc_busy_clear_one(mp, pag, busyp);
}
if (pag) {
diff --git a/fs/xfs/xfs_alloc.h b/fs/xfs/xfs_alloc.h
index 240ad288f2f99d7b6805591460846ce6a4c905b8..06aa8217452b511811b631fa50be303bba6dc56b 100644
--- a/fs/xfs/xfs_alloc.h
+++ b/fs/xfs/xfs_alloc.h
@@ -140,7 +140,8 @@ 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 list_head *list);
+xfs_alloc_busy_clear(struct xfs_mount *mp, struct list_head *list,
+ bool do_discard);
int
xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index 7d56e88a3f0eb6c671e863c4977d2f47a500b830..c7755d5a5fbe967ed58bb04ffcc0d47d082a87e4 100644
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -29,6 +29,7 @@
#include "xfs_mount.h"
#include "xfs_error.h"
#include "xfs_alloc.h"
+#include "xfs_discard.h"
/*
* Perform initial CIL structure initialisation. If the CIL is not
@@ -361,18 +362,28 @@ xlog_cil_committed(
int abort)
{
struct xfs_cil_ctx *ctx = args;
+ struct xfs_mount *mp = ctx->cil->xc_log->l_mp;
xfs_trans_committed_bulk(ctx->cil->xc_log->l_ailp, ctx->lv_chain,
ctx->start_lsn, abort);
xfs_alloc_busy_sort(&ctx->busy_extents);
- xfs_alloc_busy_clear(ctx->cil->xc_log->l_mp, &ctx->busy_extents);
+ xfs_alloc_busy_clear(mp, &ctx->busy_extents,
+ (mp->m_flags & XFS_MOUNT_DISCARD) && !abort);
spin_lock(&ctx->cil->xc_cil_lock);
list_del(&ctx->committing);
spin_unlock(&ctx->cil->xc_cil_lock);
xlog_cil_free_logvec(ctx->lv_chain);
+
+ if (!list_empty(&ctx->busy_extents)) {
+ ASSERT(mp->m_flags & XFS_MOUNT_DISCARD);
+
+ xfs_discard_extents(mp, &ctx->busy_extents);
+ xfs_alloc_busy_clear(mp, &ctx->busy_extents, false);
+ }
+
kmem_free(ctx);
}
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 19af0ab0d0c6c6c1cab862016dbe258263e39d31..3d68bb267c5fc064279c5545cf2039974c89fa7b 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -224,6 +224,7 @@ typedef struct xfs_mount {
#define XFS_MOUNT_FS_SHUTDOWN (1ULL << 4) /* atomic stop of all filesystem
operations, typically for
disk errors in metadata */
+#define XFS_MOUNT_DISCARD (1ULL << 5) /* discard unused blocks */
#define XFS_MOUNT_RETERR (1ULL << 6) /* return alignment errors to
user */
#define XFS_MOUNT_NOALIGN (1ULL << 7) /* turn off stripe alignment
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index d1f24858ccc4d365db467f8bdbe222ef4511d354..7c7bc2b786bd47d6ec89e31bcf966f6dc5121ec1 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -609,7 +609,7 @@ xfs_trans_free(
struct xfs_trans *tp)
{
xfs_alloc_busy_sort(&tp->t_busy);
- xfs_alloc_busy_clear(tp->t_mountp, &tp->t_busy);
+ xfs_alloc_busy_clear(tp->t_mountp, &tp->t_busy, false);
atomic_dec(&tp->t_mountp->m_active_trans);
xfs_trans_free_dqinfo(tp);