Fwd: [PATCH] cifs: change DOS/NT/POSIX mapping of ERRnoresource

[Steve French]

Jeff's argument seems reasonable - any other comments on this (as
Samba client at one point used similar mappings of these rc)


---------- Forwarded message ----------
From: Jeff Layton <jlayton at redhat.com>
Date: Mon, Sep 24, 2012 at 8:33 AM
Subject: [PATCH] cifs: change DOS/NT/POSIX mapping of ERRnoresource
To: smfrench at gmail.com
Cc: linux-cifs at vger.kernel.org


ERRnoresource is an ERRSRV level (aka server-side) error and means "No
resources currently available for request". Currently that maps to POSIX
-ENOBUFS. No NT errors map to it currently.

NT_STATUS_INSUFFICIENT_RESOURCES and NT_STATUS_INSUFF_SERVER_RESOURCES
are also similar in meaning. Currently the client maps those to
ERRnomem, which maps to -ENOMEM in POSIX.

All of these mappings seem to be quite wrong to me and are confusing for
users. All of the above errors indicate problems on the server, not the
client. Reporting -ENOMEM or -ENOBUFS implies that the client is running
out of resources.

This patch changes those mappings. The NT_* errors are changed to map to
the SRV level ERRnoresource. That error is in turn changed to return
-EREMOTEIO which is the only POSIX error I could find that conveys that
something went wrong on the server. While we're at it, change the SMB2
equivalent error to return the same.

Signed-off-by: Jeff Layton <jlayton at redhat.com>
---
 fs/cifs/netmisc.c      | 6 +++---
 fs/cifs/smb2maperror.c | 3 ++-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/fs/cifs/netmisc.c b/fs/cifs/netmisc.c
index e7bab3b..d5ce9e2 100644
--- a/fs/cifs/netmisc.c
+++ b/fs/cifs/netmisc.c
@@ -110,7 +110,7 @@ static const struct smb_to_posix_error
mapping_table_ERRSRV[] = {
        {ERRnoroom, -ENOSPC},
        {ERRrmuns, -EUSERS},
        {ERRtimeout, -ETIME},
-       {ERRnoresource, -ENOBUFS},
+       {ERRnoresource, -EREMOTEIO},
        {ERRtoomanyuids, -EUSERS},
        {ERRbaduid, -EACCES},
        {ERRusempx, -EIO},
@@ -412,7 +412,7 @@ static const struct {
         from NT_STATUS_INSUFFICIENT_RESOURCES to
         NT_STATUS_INSUFF_SERVER_RESOURCES during the session setup } */
        {
-       ERRDOS, ERRnomem, NT_STATUS_INSUFFICIENT_RESOURCES}, {
+       ERRDOS, ERRnoresource, NT_STATUS_INSUFFICIENT_RESOURCES}, {
        ERRDOS, ERRbadpath, NT_STATUS_DFS_EXIT_PATH_FOUND}, {
        ERRDOS, 23, NT_STATUS_DEVICE_DATA_ERROR}, {
        ERRHRD, ERRgeneral, NT_STATUS_DEVICE_NOT_CONNECTED}, {
@@ -682,7 +682,7 @@ static const struct {
        ERRHRD, ERRgeneral, NT_STATUS_NO_USER_SESSION_KEY}, {
        ERRDOS, 59, NT_STATUS_USER_SESSION_DELETED}, {
        ERRHRD, ERRgeneral, NT_STATUS_RESOURCE_LANG_NOT_FOUND}, {
-       ERRDOS, ERRnomem, NT_STATUS_INSUFF_SERVER_RESOURCES}, {
+       ERRDOS, ERRnoresource, NT_STATUS_INSUFF_SERVER_RESOURCES}, {
        ERRHRD, ERRgeneral, NT_STATUS_INVALID_BUFFER_SIZE}, {
        ERRHRD, ERRgeneral, NT_STATUS_INVALID_ADDRESS_COMPONENT}, {
        ERRHRD, ERRgeneral, NT_STATUS_INVALID_ADDRESS_WILDCARD}, {
diff --git a/fs/cifs/smb2maperror.c b/fs/cifs/smb2maperror.c
index eaf5466..494c912 100644
--- a/fs/cifs/smb2maperror.c
+++ b/fs/cifs/smb2maperror.c
@@ -453,7 +453,8 @@ static const struct status_to_posix_error
smb2_error_map_table[] = {
        {STATUS_FILE_INVALID, -EIO, "STATUS_FILE_INVALID"},
        {STATUS_ALLOTTED_SPACE_EXCEEDED, -EIO,
        "STATUS_ALLOTTED_SPACE_EXCEEDED"},
-       {STATUS_INSUFFICIENT_RESOURCES, -EIO, "STATUS_INSUFFICIENT_RESOURCES"},
+       {STATUS_INSUFFICIENT_RESOURCES, -EREMOTEIO,
+                               "STATUS_INSUFFICIENT_RESOURCES"},
        {STATUS_DFS_EXIT_PATH_FOUND, -EIO, "STATUS_DFS_EXIT_PATH_FOUND"},
        {STATUS_DEVICE_DATA_ERROR, -EIO, "STATUS_DEVICE_DATA_ERROR"},
        {STATUS_DEVICE_NOT_CONNECTED, -EIO, "STATUS_DEVICE_NOT_CONNECTED"},
--
1.7.11.4



-- 
Thanks,

Steve