diff options
| author | Pavel Shilovsky <pshilov@microsoft.com> | 2019-01-23 18:15:52 -0800 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2019-03-05 18:10:01 -0600 |
| commit | 9a1c67e8d5dad143d5166dac1ee6776f433dac00 (patch) | |
| tree | 3af988a600e442519eb6cee59b8dec7499b1c3e5 /fs/cifs/smb2ops.c | |
| parent | 97ea499883cc0566b1fafdc12ca49d0926aab332 (diff) | |
CIFS: Adjust MTU credits before reopening a file
Currently we adjust MTU credits before sending an IO request
and after reopening a file. This approach doesn't allow the
reopen routine to use existing credits that are not needed
for IO. Reorder credit adjustment and reopening a file to
use credits available to the client more efficiently. Also
unwrap complex if statement into few pieces to improve
readability.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs/smb2ops.c')
| -rw-r--r-- | fs/cifs/smb2ops.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 6f1a5f504c02..085e91436da7 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -222,6 +222,38 @@ smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size, return rc; } +static int +smb2_adjust_credits(struct TCP_Server_Info *server, + struct cifs_credits *credits, + const unsigned int payload_size) +{ + int new_val = DIV_ROUND_UP(payload_size, SMB2_MAX_BUFFER_SIZE); + + if (!credits->value || credits->value == new_val) + return 0; + + if (credits->value < new_val) { + WARN_ONCE(1, "request has less credits (%d) than required (%d)", + credits->value, new_val); + return -ENOTSUPP; + } + + spin_lock(&server->req_lock); + + if (server->reconnect_instance != credits->instance) { + spin_unlock(&server->req_lock); + cifs_dbg(VFS, "trying to return %d credits to old session\n", + credits->value - new_val); + return -EAGAIN; + } + + server->credits += credits->value - new_val; + spin_unlock(&server->req_lock); + wake_up(&server->request_q); + credits->value = new_val; + return 0; +} + static __u64 smb2_get_next_mid(struct TCP_Server_Info *server) { @@ -3678,6 +3710,7 @@ struct smb_version_operations smb21_operations = { .get_credits_field = smb2_get_credits_field, .get_credits = smb2_get_credits, .wait_mtu_credits = smb2_wait_mtu_credits, + .adjust_credits = smb2_adjust_credits, .get_next_mid = smb2_get_next_mid, .revert_current_mid = smb2_revert_current_mid, .read_data_offset = smb2_read_data_offset, @@ -3775,6 +3808,7 @@ struct smb_version_operations smb30_operations = { .get_credits_field = smb2_get_credits_field, .get_credits = smb2_get_credits, .wait_mtu_credits = smb2_wait_mtu_credits, + .adjust_credits = smb2_adjust_credits, .get_next_mid = smb2_get_next_mid, .revert_current_mid = smb2_revert_current_mid, .read_data_offset = smb2_read_data_offset, @@ -3881,6 +3915,7 @@ struct smb_version_operations smb311_operations = { .get_credits_field = smb2_get_credits_field, .get_credits = smb2_get_credits, .wait_mtu_credits = smb2_wait_mtu_credits, + .adjust_credits = smb2_adjust_credits, .get_next_mid = smb2_get_next_mid, .revert_current_mid = smb2_revert_current_mid, .read_data_offset = smb2_read_data_offset, |