Would this slow things down much at boot time when you do have e.g. 3
mounts ... would end up serializing a bit more?
On Mon, Jan 17, 2022 at 8:17 PM Ronnie Sahlberg <lsahlber@xxxxxxxxxx> wrote:
>
> RHBZ: 2008434
>
> Some servers, such as Windows2016 have a very low number of concurrent mounts that
> they allow from each client.
> This can be a problem if you have a more than a handful (==3 in this case)
> of cifs entries in your fstab and cause a number of the mounts there to randomly fail.
>
> Add a global mutex and use it to serialize all mount attempts.
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> ---
> fs/cifs/fs_context.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> index e3ed25dc6f3f..7ec35f3f0a5f 100644
> --- a/fs/cifs/fs_context.c
> +++ b/fs/cifs/fs_context.c
> @@ -37,6 +37,8 @@
> #include "rfc1002pdu.h"
> #include "fs_context.h"
>
> +static DEFINE_MUTEX(cifs_mount_mutex);
> +
> static const match_table_t cifs_smb_version_tokens = {
> { Smb_1, SMB1_VERSION_STRING },
> { Smb_20, SMB20_VERSION_STRING},
> @@ -707,10 +709,14 @@ static int smb3_get_tree_common(struct fs_context *fc)
> static int smb3_get_tree(struct fs_context *fc)
> {
> int err = smb3_fs_context_validate(fc);
> + int ret;
>
> if (err)
> return err;
> - return smb3_get_tree_common(fc);
> + mutex_lock(&cifs_mount_mutex);
> + ret = smb3_get_tree_common(fc);
> + mutex_unlock(&cifs_mount_mutex);
> + return ret;
> }
>
> static void smb3_fs_context_free(struct fs_context *fc)
> --
> 2.30.2
>
--
Thanks,
Steve
