5.10-stable review patch. If anyone has any objections, please let me know.
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From: J. Bruce Fields bfields@redhat.com
[ Upstream commit b840be2f00c0bc00d993f8f76e251052b83e4382 ]
As in the v4 case, it doesn't work well to block waiting for a lock on an nfs filesystem.
As in the v4 case, that means we're depending on the client to poll. It's probably incorrect to depend on that, but I *think* clients do poll in practice. In any case, it's an improvement over hanging the lockd thread indefinitely as we currently are.
Signed-off-by: J. Bruce Fields bfields@redhat.com Acked-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/lockd/svclock.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index a7b4c51667ada..e9b85d8fd5fe7 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -31,6 +31,7 @@ #include <linux/lockd/nlm.h> #include <linux/lockd/lockd.h> #include <linux/kthread.h> +#include <linux/exportfs.h>
#define NLMDBG_FACILITY NLMDBG_SVCLOCK
@@ -470,18 +471,24 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, struct nlm_cookie *cookie, int reclaim) { struct nlm_block *block = NULL; + struct inode *inode = nlmsvc_file_inode(file); int error; int mode; + int async_block = 0; __be32 ret;
dprintk("lockd: nlmsvc_lock(%s/%ld, ty=%d, pi=%d, %Ld-%Ld, bl=%d)\n", - nlmsvc_file_inode(file)->i_sb->s_id, - nlmsvc_file_inode(file)->i_ino, + inode->i_sb->s_id, inode->i_ino, lock->fl.fl_type, lock->fl.fl_pid, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end, wait);
+ if (inode->i_sb->s_export_op->flags & EXPORT_OP_SYNC_LOCKS) { + async_block = wait; + wait = 0; + } + /* Lock file against concurrent access */ mutex_lock(&file->f_mutex); /* Get existing block (in case client is busy-waiting) @@ -542,7 +549,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, */ if (wait) break; - ret = nlm_lck_denied; + ret = async_block ? nlm_lck_blocked : nlm_lck_denied; goto out; case FILE_LOCK_DEFERRED: if (wait)