This is a note to let you know that I've just added the patch titled
cifs: return a single-use cfid if we did not get a lease
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cifs-return-a-single-use-cfid-if-we-did-not-get-a-lease.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8e843bf38f7be0766642a91523cfa65f2b021a8a Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Date: Fri, 17 Feb 2023 13:35:01 +1000
Subject: cifs: return a single-use cfid if we did not get a lease
From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
commit 8e843bf38f7be0766642a91523cfa65f2b021a8a upstream.
If we did not get a lease we can still return a single use cfid to the caller.
The cfid will not have has_lease set and will thus not be shared with any
other concurrent users and will be freed immediately when the caller
drops the handle.
This avoids extra roundtrips for servers that do not support directory leases
where they would first fail to get a cfid with a lease and then fallback
to try a normal SMB2_open()
Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Bharath SM <bharathsm@xxxxxxxxxxxxx>
Reviewed-by: Paulo Alcantara (SUSE) <pc@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/cached_dir.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
--- a/fs/cifs/cached_dir.c
+++ b/fs/cifs/cached_dir.c
@@ -14,6 +14,7 @@
static struct cached_fid *init_cached_dir(const char *path);
static void free_cached_dir(struct cached_fid *cfid);
+static void smb2_close_cached_fid(struct kref *ref);
static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids,
const char *path,
@@ -221,6 +222,7 @@ int open_cached_dir(unsigned int xid, st
}
goto oshr_free;
}
+ cfid->tcon = tcon;
cfid->is_open = true;
o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
@@ -233,7 +235,6 @@ int open_cached_dir(unsigned int xid, st
if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE)
goto oshr_free;
-
smb2_parse_contexts(server, o_rsp,
&oparms.fid->epoch,
oparms.fid->lease_key, &oplock,
@@ -260,7 +261,6 @@ int open_cached_dir(unsigned int xid, st
}
}
cfid->dentry = dentry;
- cfid->tcon = tcon;
cfid->time = jiffies;
cfid->has_lease = true;
@@ -271,7 +271,7 @@ oshr_free:
free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
spin_lock(&cfids->cfid_list_lock);
- if (!cfid->has_lease) {
+ if (rc && !cfid->has_lease) {
if (cfid->on_list) {
list_del(&cfid->entry);
cfid->on_list = false;
@@ -280,6 +280,15 @@ oshr_free:
rc = -ENOENT;
}
spin_unlock(&cfids->cfid_list_lock);
+ if (!rc && !cfid->has_lease) {
+ /*
+ * We are guaranteed to have two references at this point.
+ * One for the caller and one for a potential lease.
+ * Release the Lease-ref so that the directory will be closed
+ * when the caller closes the cached handle.
+ */
+ kref_put(&cfid->refcount, smb2_close_cached_fid);
+ }
if (rc) {
if (cfid->is_open)
SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
@@ -340,6 +349,7 @@ smb2_close_cached_fid(struct kref *ref)
if (cfid->is_open) {
SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
cfid->fid.volatile_fid);
+ atomic_dec(&cfid->tcon->num_remote_opens);
}
free_cached_dir(cfid);
Patches currently in stable-queue which might be from lsahlber@xxxxxxxxxx are
queue-6.2/cifs-improve-checking-of-dfs-links-over-status_object_name_invalid.patch
queue-6.2/cifs-return-a-single-use-cfid-if-we-did-not-get-a-lease.patch
queue-6.2/cifs-fix-mount-on-old-smb-servers.patch
queue-6.2/cifs-check-the-lease-context-if-we-actually-got-a-lease.patch
