From: Olga Kornievskaia <kolga@xxxxxxxxxx>
In 4.1+, the server is allowed to set a flag
NFS4_RESULT_PRESERVE_UNLINKED in reply to the OPEN, that tells
the client that it does not need to do a silly rename of an
opened file when it's being removed.
Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
---
fs/nfs/dir.c | 10 ++++++++--
fs/nfs/nfs4proc.c | 2 ++
include/linux/nfs_fs.h | 1 +
include/uapi/linux/nfs4.h | 1 +
4 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 00b222e48d6f..4225d9463ba6 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1404,7 +1404,12 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
if (flags & LOOKUP_REVAL)
goto out_force;
out:
- return (inode->i_nlink == 0) ? -ESTALE : 0;
+ if (inode->i_nlink > 0 || (inode->i_nlink == 0 &&
+ test_bit(NFS_INO_PRESERVE_UNLINKED,
+ &NFS_I(inode)->flags)))
+ return 0;
+ else
+ return -ESTALE;
out_force:
if (flags & LOOKUP_RCU)
return -ECHILD;
@@ -2315,7 +2320,8 @@ int nfs_unlink(struct inode *dir, struct dentry *dentry)
trace_nfs_unlink_enter(dir, dentry);
spin_lock(&dentry->d_lock);
- if (d_count(dentry) > 1) {
+ if (d_count(dentry) > 1 && !test_bit(NFS_INO_PRESERVE_UNLINKED,
+ &NFS_I(d_inode(dentry))->flags)) {
spin_unlock(&dentry->d_lock);
/* Start asynchronous writeout of the inode */
write_inode_now(d_inode(dentry), 0);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2fbe04d12e44..2cbade53c8d3 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3073,6 +3073,8 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
set_bit(NFS_STATE_POSIX_LOCKS, &state->flags);
if (opendata->o_res.rflags & NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK)
set_bit(NFS_STATE_MAY_NOTIFY_LOCK, &state->flags);
+ if (opendata->o_res.rflags & NFS4_OPEN_RESULT_PRESERVE_UNLINKED)
+ set_bit(NFS_INO_PRESERVE_UNLINKED, &NFS_I(state->inode)->flags);
dentry = opendata->dentry;
if (d_really_is_negative(dentry)) {
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 7a134e4c03e8..ea58d96354a9 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -290,6 +290,7 @@ struct nfs4_copy_state {
#define NFS_INO_STALE (1) /* possible stale inode */
#define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
#define NFS_INO_INVALIDATING (3) /* inode is being invalidated */
+#define NFS_INO_PRESERVE_UNLINKED (4) /* preserve file if removed while open */
#define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
#define NFS_INO_FSCACHE_LOCK (6) /* FS-Cache cookie management lock */
#define NFS_INO_FORCE_READDIR (7) /* force readdirplus */
diff --git a/include/uapi/linux/nfs4.h b/include/uapi/linux/nfs4.h
index 800bb0ffa6e6..14acfe5300b7 100644
--- a/include/uapi/linux/nfs4.h
+++ b/include/uapi/linux/nfs4.h
@@ -46,6 +46,7 @@
#define NFS4_OPEN_RESULT_CONFIRM 0x0002
#define NFS4_OPEN_RESULT_LOCKTYPE_POSIX 0x0004
#define NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK 0x0020
+#define NFS4_OPEN_RESULT_PRESERVE_UNLINKED 0x0008
#define NFS4_SHARE_ACCESS_MASK 0x000F
#define NFS4_SHARE_ACCESS_READ 0x0001
--
2.27.0
