(also minor cleanup of pnfs_free_layout())
Signed-off-by: Alexandros Batsakis <batsakis@xxxxxxxxxx>
Conflicts:
fs/nfs/pnfs.c
---
fs/nfs/pnfs.c | 80 +++++++++++++++++++++++++++++++++++++-------------------
1 files changed, 53 insertions(+), 27 deletions(-)
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index b72c013..74cb998 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1,4 +1,4 @@
-/*
+ /*
* linux/fs/nfs/pnfs.c
*
* pNFS functions to call and manage layout drivers.
@@ -60,6 +60,8 @@ static int pnfs_initialized;
static void pnfs_free_layout(struct pnfs_layout_type *lo,
struct nfs4_pnfs_layout_segment *range);
static enum pnfs_try_status pnfs_commit(struct nfs_write_data *data, int sync);
+static inline void lock_current_layout(struct nfs_inode *nfsi);
+static inline void unlock_current_layout(struct nfs_inode *nfsi);
/* Locking:
*
@@ -153,16 +155,17 @@ pnfs_need_layoutcommit(struct nfs_inode *nfsi, struct nfs_open_context *ctx)
{
dprintk("%s: has_layout=%d layoutcommit_ctx=%p ctx=%p\n", __func__,
has_layout(nfsi), nfsi->layout.layoutcommit_ctx, ctx);
- spin_lock(&nfsi->lo_lock);
+
+ lock_current_layout(nfsi);
if (has_layout(nfsi) && !nfsi->layout.layoutcommit_ctx) {
nfsi->layout.layoutcommit_ctx = get_nfs_open_context(ctx);
nfsi->change_attr++;
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
dprintk("%s: Set layoutcommit_ctx=%p\n", __func__,
nfsi->layout.layoutcommit_ctx);
return;
}
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
}
/* Update last_write_offset for layoutcommit.
@@ -175,7 +178,7 @@ pnfs_update_last_write(struct nfs_inode *nfsi, loff_t offset, size_t extent)
{
loff_t end_pos;
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
if (offset < nfsi->layout.pnfs_write_begin_pos)
nfsi->layout.pnfs_write_begin_pos = offset;
end_pos = offset + extent - 1; /* I'm being inclusive */
@@ -187,7 +190,7 @@ pnfs_update_last_write(struct nfs_inode *nfsi, loff_t offset, size_t extent)
(unsigned long) offset ,
(unsigned long) nfsi->layout.pnfs_write_begin_pos,
(unsigned long) nfsi->layout.pnfs_write_end_pos);
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
}
/* Unitialize a mountpoint in a layout driver */
@@ -296,12 +299,27 @@ pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
* pNFS client layout cache
*/
#if defined(CONFIG_SMP)
+#define BUG_ON_LOCKED_LO(lo) \
+ BUG_ON(spin_is_locked(&PNFS_NFS_INODE(lo)->lo_lock))
#define BUG_ON_UNLOCKED_LO(lo) \
BUG_ON(!spin_is_locked(&PNFS_NFS_INODE(lo)->lo_lock))
#else /* CONFIG_SMP */
+#define BUG_ON_LOCKED_LO(lo) do {} while (0)
#define BUG_ON_UNLOCKED_LO(lo) do {} while (0)
#endif /* CONFIG_SMP */
+static inline void lock_current_layout(struct nfs_inode *nfsi)
+{
+ BUG_ON_LOCKED_LO((&nfsi->layout));
+ spin_lock(&nfsi->lo_lock);
+}
+
+static inline void unlock_current_layout(struct nfs_inode *nfsi)
+{
+ BUG_ON_UNLOCKED_LO((&nfsi->layout));
+ spin_unlock(&nfsi->lo_lock);
+}
+
/*
* get and lock nfsi->layout
*/
@@ -310,10 +328,10 @@ get_lock_current_layout(struct nfs_inode *nfsi)
{
struct pnfs_layout_type *lo;
+ lock_current_layout(nfsi);
lo = &nfsi->layout;
- spin_lock(&nfsi->lo_lock);
if (!lo->ld_data) {
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
return NULL;
}
@@ -333,7 +351,12 @@ put_unlock_current_layout(struct pnfs_layout_type *lo)
BUG_ON_UNLOCKED_LO(lo);
BUG_ON(lo->refcount <= 0);
- if (--lo->refcount == 0 && list_empty(&lo->segs)) {
+ lo->refcount--;
+
+ if (lo->refcount > 0)
+ goto out;
+
+ if (list_empty(&lo->segs)) {
struct layoutdriver_io_operations *io_ops =
PNFS_LD_IO_OPS(lo);
@@ -347,7 +370,8 @@ put_unlock_current_layout(struct pnfs_layout_type *lo)
list_del_init(&nfsi->lo_inodes);
spin_unlock(&clp->cl_lock);
}
- spin_unlock(&nfsi->lo_lock);
+out:
+ unlock_current_layout(nfsi);
}
void
@@ -356,7 +380,7 @@ pnfs_layout_release(struct pnfs_layout_type *lo, atomic_t *count,
{
struct nfs_inode *nfsi = PNFS_NFS_INODE(lo);
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
if (range)
pnfs_free_layout(lo, range);
atomic_dec(count);
@@ -375,6 +399,8 @@ pnfs_destroy_layout(struct nfs_inode *nfsi)
};
lo = get_lock_current_layout(nfsi);
+ if (!lo)
+ return;
pnfs_free_layout(lo, &range);
put_unlock_current_layout(lo);
}
@@ -652,7 +678,7 @@ pnfs_return_layout_barrier(struct nfs_inode *nfsi,
struct pnfs_layout_segment *lseg;
bool ret = false;
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
list_for_each_entry (lseg, &nfsi->layout.segs, fi_list) {
if (!should_free_lseg(lseg, range))
continue;
@@ -666,7 +692,7 @@ pnfs_return_layout_barrier(struct nfs_inode *nfsi,
}
if (atomic_read(&nfsi->layout.lgetcount))
ret = true;
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
dprintk("%s:Return %d\n", __func__, ret);
return ret;
@@ -756,7 +782,7 @@ _pnfs_return_layout(struct inode *ino, struct nfs4_pnfs_layout_segment *range,
/* unlock w/o put rebalanced by eventual call to
* pnfs_layout_release
*/
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
if (pnfs_return_layout_barrier(nfsi, &arg)) {
dprintk("%s: waiting\n", __func__);
@@ -887,7 +913,7 @@ static int pnfs_wait_schedule(void *word)
*
* Note: If successful, nfsi->lo_lock is taken and the caller
* must put and unlock current_layout by using put_unlock_current_layout()
- * when the returned layout is released.
+ * directly or pnfs_layout_release() when the returned layout is released.
*/
static struct pnfs_layout_type *
get_lock_alloc_layout(struct inode *ino)
@@ -922,7 +948,7 @@ get_lock_alloc_layout(struct inode *ino)
struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
/* must grab the layout lock before the client lock */
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
spin_lock(&clp->cl_lock);
if (list_empty(&nfsi->lo_inodes))
@@ -1038,10 +1064,10 @@ void drain_layoutreturns(struct pnfs_layout_type *lo)
while (atomic_read(&lo->lretcount)) {
struct nfs_inode *nfsi = PNFS_NFS_INODE(lo);
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
dprintk("%s: waiting\n", __func__);
wait_event(nfsi->lo_waitq, (atomic_read(&lo->lretcount) == 0));
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
}
}
@@ -1080,13 +1106,13 @@ pnfs_update_layout(struct inode *ino,
/* Check to see if the layout for the given range already exists */
lseg = pnfs_has_layout(lo, &arg, take_ref, !take_ref);
if (lseg && !lseg->valid) {
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
if (take_ref)
put_lseg(lseg);
for (;;) {
prepare_to_wait(&nfsi->lo_waitq, &__wait,
TASK_KILLABLE);
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
lseg = pnfs_has_layout(lo, &arg, take_ref, !take_ref);
if (!lseg || lseg->valid)
break;
@@ -1099,7 +1125,7 @@ pnfs_update_layout(struct inode *ino,
result = -ERESTARTSYS;
break;
}
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
schedule();
}
finish_wait(&nfsi->lo_waitq, &__wait);
@@ -1136,7 +1162,7 @@ pnfs_update_layout(struct inode *ino,
/* Matching dec is done in .rpc_release (on non-error paths) */
atomic_inc(&lo->lgetcount);
/* Lose lock, but not reference, match this with pnfs_layout_release */
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
result = get_layout(ino, ctx, &arg, lsegpp, lo);
out:
@@ -1286,7 +1312,7 @@ pnfs_layout_process(struct nfs4_pnfs_layoutget *lgp)
*lgp->lsegpp = lseg;
}
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
pnfs_insert_layout(lo, lseg);
if (res->return_on_close) {
@@ -1297,7 +1323,7 @@ pnfs_layout_process(struct nfs4_pnfs_layoutget *lgp)
/* Done processing layoutget. Set the layout stateid */
pnfs_set_layout_stateid(lo, &res->stateid);
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
out:
return status;
}
@@ -2212,7 +2238,7 @@ pnfs_layoutcommit_inode(struct inode *inode, int sync)
if (!data)
return -ENOMEM;
- spin_lock(&nfsi->lo_lock);
+ lock_current_layout(nfsi);
if (!nfsi->layout.layoutcommit_ctx)
goto out_unlock;
@@ -2233,7 +2259,7 @@ pnfs_layoutcommit_inode(struct inode *inode, int sync)
nfsi->layout.layoutcommit_ctx = NULL;
/* release lock on pnfs layoutcommit attrs */
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
data->is_sync = sync;
status = pnfs4_proc_layoutcommit(data);
@@ -2242,7 +2268,7 @@ out:
return status;
out_unlock:
pnfs_layoutcommit_free(data);
- spin_unlock(&nfsi->lo_lock);
+ unlock_current_layout(nfsi);
goto out;
}
--
1.6.2.5
--
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