diff options
Diffstat (limited to '0223-change-get_real_filename-implementation-to-use-ENOAT.patch')
| -rw-r--r-- | 0223-change-get_real_filename-implementation-to-use-ENOAT.patch | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/0223-change-get_real_filename-implementation-to-use-ENOAT.patch b/0223-change-get_real_filename-implementation-to-use-ENOAT.patch new file mode 100644 index 0000000..a533388 --- /dev/null +++ b/0223-change-get_real_filename-implementation-to-use-ENOAT.patch @@ -0,0 +1,123 @@ +From 36b0bd86321436a951f225fcf2e921390ed8dc33 Mon Sep 17 00:00:00 2001 +From: Michael Adam <obnox@samba.org> +Date: Thu, 20 Jun 2019 13:09:37 +0200 +Subject: [PATCH 223/255] change get_real_filename implementation to use + ENOATTR instead of ENOENT + +get_real_filename is implemented as a virtual extended attribute to help +Samba implement the case-insensitive but case preserving SMB protocol +more efficiently. It is implemented as a getxattr call on the parent directory +with the virtual key of "get_real_filename:<entryname>" by looking for a +spelling with different case for the provided file/dir name (<entryname>) +and returning this correct spelling as a result if the entry is found. +Originally (05aaec645a6262d431486eb5ac7cd702646cfcfb), the +implementation used the ENOENT errno to return the authoritative answer +that <entryname> does not exist in any case folding. + +Now this implementation is actually a violation or misuse of the defined +API for the getxattr call which returns ENOENT for the case that the dir +that the call is made against does not exist and ENOATTR (or the synonym +ENODATA) for the case that the xattr does not exist. + +This was not a problem until the gluster fuse-bridge was changed +to do map ENOENT to ESTALE in 59629f1da9dca670d5dcc6425f7f89b3e96b46bf, +after which we the getxattr call for get_real_filename returned an +ESTALE instead of ENOENT breaking the expectation in Samba. + +It is an independent problem that ESTALE should not leak out to user +space but is intended to trigger retries between fuse and gluster. +But nevertheless, the semantics seem to be incorrect here and should +be changed. + +This patch changes the implementation of the get_real_filename virtual +xattr to correctly return ENOATTR instead of ENOENT if the file/directory +being looked up is not found. + +The Samba glusterfs_fuse vfs module which takes advantage of the +get_real_filename over a fuse mount will receive a corresponding change +to map ENOATTR to ENOENT. Without this change, it will still work +correctly, but the performance optimization for nonexisting files is +lost. On the other hand side, this change removes the distinction +between the old not-implemented case and the implemented case. +So Samba changed to treat ENOATTR like ENOENT will not work correctly +any more against old servers that don't implement get_real_filename. +I.e. existing files will be reported as non-existing + +Backport of https://review.gluster.org/c/glusterfs/+/22925 + +Change-Id: I971b427ab8410636d5d201157d9af70e0d075b67 +fixes: bz#1724089 +Signed-off-by: Michael Adam <obnox@samba.org> +Reviewed-on: https://code.engineering.redhat.com/gerrit/175012 +Tested-by: RHGS Build Bot <nigelb@redhat.com> +Reviewed-by: Atin Mukherjee <amukherj@redhat.com> +--- + xlators/cluster/dht/src/dht-common.c | 8 ++++---- + xlators/storage/posix/src/posix-inode-fd-ops.c | 4 ++-- + 2 files changed, 6 insertions(+), 6 deletions(-) + +diff --git a/xlators/cluster/dht/src/dht-common.c b/xlators/cluster/dht/src/dht-common.c +index 9a6ea5b..219b072 100644 +--- a/xlators/cluster/dht/src/dht-common.c ++++ b/xlators/cluster/dht/src/dht-common.c +@@ -4618,7 +4618,7 @@ dht_getxattr_get_real_filename_cbk(call_frame_t *frame, void *cookie, + + LOCK(&frame->lock); + { +- if (local->op_errno == ENODATA || local->op_errno == EOPNOTSUPP) { ++ if (local->op_errno == EOPNOTSUPP) { + /* Nothing to do here, we have already found + * a subvol which does not have the get_real_filename + * optimization. If condition is for simple logic. +@@ -4627,7 +4627,7 @@ dht_getxattr_get_real_filename_cbk(call_frame_t *frame, void *cookie, + } + + if (op_ret == -1) { +- if (op_errno == ENODATA || op_errno == EOPNOTSUPP) { ++ if (op_errno == EOPNOTSUPP) { + /* This subvol does not have the optimization. + * Better let the user know we don't support it. + * Remove previous results if any. +@@ -4655,7 +4655,7 @@ dht_getxattr_get_real_filename_cbk(call_frame_t *frame, void *cookie, + goto post_unlock; + } + +- if (op_errno == ENOENT) { ++ if (op_errno == ENOATTR) { + /* Do nothing, our defaults are set to this. + */ + goto unlock; +@@ -4723,7 +4723,7 @@ dht_getxattr_get_real_filename(call_frame_t *frame, xlator_t *this, loc_t *loc, + cnt = local->call_cnt = layout->cnt; + + local->op_ret = -1; +- local->op_errno = ENOENT; ++ local->op_errno = ENOATTR; + + for (i = 0; i < cnt; i++) { + subvol = layout->list[i].xlator; +diff --git a/xlators/storage/posix/src/posix-inode-fd-ops.c b/xlators/storage/posix/src/posix-inode-fd-ops.c +index c949f68..ea3b69c 100644 +--- a/xlators/storage/posix/src/posix-inode-fd-ops.c ++++ b/xlators/storage/posix/src/posix-inode-fd-ops.c +@@ -2954,7 +2954,7 @@ posix_xattr_get_real_filename(call_frame_t *frame, xlator_t *this, loc_t *loc, + (void)sys_closedir(fd); + + if (!found) +- return -ENOENT; ++ return -ENOATTR; + + ret = dict_set_dynstr(dict, (char *)key, found); + if (ret) { +@@ -3422,7 +3422,7 @@ posix_getxattr(call_frame_t *frame, xlator_t *this, loc_t *loc, + if (ret < 0) { + op_ret = -1; + op_errno = -ret; +- if (op_errno == ENOENT) { ++ if (op_errno == ENOATTR) { + gf_msg_debug(this->name, 0, + "Failed to get " + "real filename (%s, %s)", +-- +1.8.3.1 + |