summaryrefslogtreecommitdiffstats
path: root/fs/ceph/snap.c
AgeCommit message (Collapse)Author
2013-05-01ceph: use ceph_create_snap_context()Alex Elder
Now that we have a library routine to create snap contexts, use it. This is part of: http://tracker.ceph.com/issues/4857 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-07-30ceph: define snap counts as u32 everywhereAlex Elder
There are two structures in which a count of snapshots are maintained: struct ceph_snap_context { ... u32 num_snaps; ... } and struct ceph_snap_realm { ... u32 num_prior_parent_snaps; /* had prior to parent_since */ ... u32 num_snaps; ... } These fields never take on negative values (e.g., to hold special meaning), and so are really inherently unsigned. Furthermore they take their value from over-the-wire or on-disk formatted 32-bit values. So change their definition to have type u32, and change some spots elsewhere in the code to account for this change. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-05-31introduce SIZE_MAXXi Wang
ULONG_MAX is often used to check for integer overflow when calculating allocation size. While ULONG_MAX happens to work on most systems, there is no guarantee that `size_t' must be the same size as `long'. This patch introduces SIZE_MAX, the maximum value of `size_t', to improve portability and readability for allocation size validation. Signed-off-by: Xi Wang <xi.wang@gmail.com> Acked-by: Alex Elder <elder@dreamhost.com> Cc: David Airlie <airlied@linux.ie> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22ceph: fix overflow check in build_snap_context()Xi Wang
The overflow check for a + n * b should be (n > (ULONG_MAX - a) / b), rather than (n > ULONG_MAX / b - a). Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: Sage Weil <sage@newdream.net>
2011-12-07ceph: use i_ceph_lock instead of i_lockSage Weil
We have been using i_lock to protect all kinds of data structures in the ceph_inode_info struct, including lists of inodes that we need to iterate over while avoiding races with inode destruction. That requires grabbing a reference to the inode with the list lock protected, but igrab() now takes i_lock to check the inode flags. Changing the list lock ordering would be a painful process. However, using a ceph-specific i_ceph_lock in the ceph inode instead of i_lock is a simple mechanical change and avoids the ordering constraints imposed by igrab(). Reported-by: Amon Ott <a.ott@m-privacy.de> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26ceph: only queue capsnap if caps are dirtySage Weil
We used to go into this branch if i_wrbuffer_ref_head was non-zero. This was an ancient check from before we were careful about dealing with all kinds of caps (and not just dirty pages). It is cleaner to only queue a capsnap if there is an actual dirty cap. If we are racing with... something...we will end up here with ci->i_wrbuffer_refs but no dirty caps. Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26ceph: fix snap writeback when racing with writesSage Weil
There are two problems that come up when we try to queue a capsnap while a write is in progress: - The FILE_WR cap is held, but not yet dirty, so we may queue a capsnap with dirty == 0. That will crash later in __ceph_flush_snaps(). Or on the FILE_WR cap if a write is in progress. - We may not have i_head_snapc set, which causes problems pretty quickly. Look to the snaprealm in this case. Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-06-07ceph: use ihold when we already have an inode refSage Weil
We should use ihold whenever we already have a stable inode ref, even when we aren't holding i_lock. This avoids adding new and unnecessary locking dependencies. Signed-off-by: Sage Weil <sage@newdream.net>
2011-05-11ceph: fix list_add in ceph_put_snap_realmHenry C Chang
Signed-off-by: Henry C Chang <henry.cy.chang@gmail.com> Signed-off-by: Sage Weil <sage@newdream.net>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-29fs: don't use igrab() while holding i_lockDave Chinner
Fix the incorrect use of igrab() inside the i_lock in NFS and Ceph‥ If we are already holding the i_lock, we have a reference to the inode so we can safely use ihold() to gain an extra reference. This avoids hangs due to lock recursion on the i_lock now that the inode_lock is gone and igrab() uses the i_lock itself. Signed-off-by: Dave Chinner <dchinner@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: Ryan Mallon <ryan@bluewatersys.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-04ceph: queue cap_snaps once per realmSage Weil
We were forming a dirty list, and then queueing cap_snaps for each realm _and_ its children, regardless of whether the children were already in the dirty list. This meant we did it twice for some realms. Which in turn meant we corrupted mdsc->snap_flush_list when the cap_snap was re-added to the list it was already on, and could trigger an infinite loop. We were also using recursion to do reach all the children, a no-no when stack is limited. Instead, (re)queue any children on the dirty list, avoiding processing anything twice and avoiding any recursion. Signed-off-by: Sage Weil <sage@newdream.net>
2010-10-20ceph: factor out libceph from Ceph file systemYehuda Sadeh
This factors out protocol and low-level storage parts of ceph into a separate libceph module living in net/ceph and include/linux/ceph. This is mostly a matter of moving files around. However, a few key pieces of the interface change as well: - ceph_client becomes ceph_fs_client and ceph_client, where the latter captures the mon and osd clients, and the fs_client gets the mds client and file system specific pieces. - Mount option parsing and debugfs setup is correspondingly broken into two pieces. - The mon client gets a generic handler callback for otherwise unknown messages (mds map, in this case). - The basic supported/required feature bits can be expanded (and are by ceph_fs_client). No functional change, aside from some subtle error handling cases that got cleaned up in the refactoring process. Signed-off-by: Sage Weil <sage@newdream.net>
2010-09-17ceph: only send one flushsnap per cap_snap per mds sessionSage Weil
Sending multiple flushsnap messages is problematic because we ignore the response if the tid doesn't match, and the server may only respond to each one once. It's also a waste. So, skip cap_snaps that are already on the flushing list, unless the caller tells us to resend (because we are reconnecting). Signed-off-by: Sage Weil <sage@newdream.net>
2010-09-16ceph: fix cap_snap and realm splitSage Weil
The cap_snap creation/queueing relies on both the current i_head_snapc _and_ the i_snap_realm pointers being correct, so that the new cap_snap can properly reference the old context and the new i_head_snapc can be updated to reference the new snaprealm's context. To fix this, we: - move inodes completely to the new (split) realm so that i_snap_realm is correct, and - generate the new snapc's _before_ queueing the cap_snaps in ceph_update_snap_trace(). Signed-off-by: Sage Weil <sage@newdream.net>
2010-09-14ceph: correctly set 'follows' in flushsnap messagesSage Weil
The 'follows' should match the seq for the snap context for the given snap cap, which is the context under which we have been dirtying and writing data and metadata. The snapshot that _contains_ those updates thus _follows_ that context's seq #. Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-24ceph: maintain i_head_snapc when any caps are dirty, not just for dataSage Weil
We used to use i_head_snapc to keep track of which snapc the current epoch of dirty data was dirtied under. It is used by queue_cap_snap to set up the cap_snap. However, since we queue cap snaps for any dirty caps, not just for dirty file data, we need to keep a valid i_head_snapc anytime we have dirty|flushing caps. This fixes a NULL pointer deref in queue_cap_snap when writing back dirty caps without data (e.g., snaptest-authwb.sh). Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-22ceph: queue cap snap writeback for realm children on snap updateSage Weil
When a realm is updated, we need to queue writeback on inodes in that realm _and_ its children. Otherwise, if the inode gets cowed on the server, we can get a hang later due to out-of-sync cap/snap state. Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-22ceph: include dirty xattrs state in snapped capsSage Weil
When we snapshot dirty metadata that needs to be written back to the MDS, include dirty xattr metadata. Make the capsnap reference the encoded xattr blob so that it will be written back in the FLUSHSNAP op. Also fix the capsnap creation guard to include dirty auth or file bits, not just tests specific to dirty file data or file writes in progress (this fixes auth metadata writeback). Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17ceph: use ceph_sb_to_client instead of ceph_clientCheng Renquan
ceph_sb_to_client and ceph_client are really identical, we need to dump one; while function ceph_client is confusing with "struct ceph_client", ceph_sb_to_client's definition is more clear; so we'd better switch all call to ceph_sb_to_client. -static inline struct ceph_client *ceph_client(struct super_block *sb) -{ - return sb->s_fs_info; -} Signed-off-by: Cheng Renquan <crquan@gmail.com> Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-03ceph: fix snap realm splitsSage Weil
The snap realm split was checking i_snap_realm, not the list_head, to determine if an inode belonged in the new realm. The check always failed, which meant we always moved the inode, corrupting the old realm's list and causing various crashes. Also wait to release old realm reference to avoid possibility of use after free. Signed-off-by: Sage Weil <sage@newdream.net>
2010-04-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: use separate class for ceph sockets' sk_lock ceph: reserve one more caps space when doing readdir ceph: queue_cap_snap should always queue dirty context ceph: fix dentry reference leak in dcache readdir ceph: decode v5 of osdmap (pool names) [protocol change] ceph: fix ack counter reset on connection reset ceph: fix leaked inode ref due to snap metadata writeback race ceph: fix snap context reference leaks ceph: allow writeback of snapped pages older than 'oldest' snapc ceph: fix dentry rehashing on virtual .snap dir
2010-04-13ceph: queue_cap_snap should always queue dirty contextSage Weil
This simplifies the calling convention, and fixes a bug where we queue a capsnap with a context other than i_head_snapc (the one that matches the dirty pages). The result was a BUG at fs/ceph/caps.c:2178 on writeback completion when a capsnap matching the writeback snapc could not be found. Signed-off-by: Sage Weil <sage@newdream.net>
2010-04-01ceph: fix leaked inode ref due to snap metadata writeback raceSage Weil
We create a ceph_cap_snap if there is dirty cap metadata (for writeback to mds) OR dirty pages (for writeback to osd). It is thus possible that the metadata has been written back to the MDS but the OSD data has not when the cap_snap is created. This results in a cap_snap with dirty(caps) == 0. The problem is that cap writeback to the MDS isn't necessary, and a FLUSHSNAP cap op gets no ack from the MDS. This leaves the cap_snap attached to the inode along with its inode reference. Fix the problem by dropping the cap_snap if it becomes 'complete' (all pages written out) and dirty(caps) == 0 in ceph_put_wrbuffer_cap_refs(). Also, BUG() in __ceph_flush_snaps() if we encounter a cap_snap with dirty(caps) == 0. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-23ceph: fix snap rebuild conditionSage Weil
We were rebuilding the snap context when it was not necessary (i.e. when the realm seq hadn't changed _and_ the parent seq was still older), which caused page snapc pointers to not match the realm's snapc pointer (even though the snap context itself was identical). This confused begin_write and put it into an endless loop. The correct logic is: rebuild snapc if _my_ realm seq changed, or if my parent realm's seq is newer than mine (and thus mine needs to be rebuilt too). Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: add missing locking to protect i_snap_realm_item during splitSage Weil
All ci->i_snap_realm_item/realm->inodes_with_caps manipulation should be protected by realm->inodes_with_caps_lock. This bug would have only bit us in a rare race with a realm split (during some snap creations). Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-23ceph: drop messages on unregistered mds sessions; cleanupSage Weil
Verify the mds session is currently registered before handling incoming messages. Clean up message handlers to pull mds out of session->s_mds instead of less trustworthy src field. Clean up con_{get,put} debug output. Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-16ceph: use rbtree for snap_realmsSage Weil
Switch from radix tree to rbtree for snap realms. This is much more appropriate given that realm keys are few and far between. Signed-off-by: Sage Weil <sage@newdream.net>
2009-12-21ceph: hex dump corrupt server data to KERN_DEBUGSage Weil
Also, print fsid using standard format, NOT hex dump. Signed-off-by: Sage Weil <sage@newdream.net>
2009-11-21ceph: remove useless IS_ERR checksSage Weil
ceph_lookup_snap_realm either returns a valid pointer or NULL; there is no need to check IS_ERR(result). Reported-by: Julia Lawall <julia@diku.dk> Signed-off-by: Sage Weil <sage@newdream.net>
2009-10-06ceph: snapshot managementSage Weil
Ceph snapshots rely on client cooperation in determining which operations apply to which snapshots, and appropriately flushing snapshotted data and metadata back to the OSD and MDS clusters. Because snapshots apply to subtrees of the file hierarchy and can be created at any time, there is a fair bit of bookkeeping required to make this work. Portions of the hierarchy that belong to the same set of snapshots are described by a single 'snap realm.' A 'snap context' describes the set of snapshots that exist for a given file or directory. Signed-off-by: Sage Weil <sage@newdream.net>