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2013-05-06btrfs: document mount options in Documentation/fs/btrfs.txtEric Sandeen
Document all current btrfs mount options. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-26vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry opJeff Layton
The following set of operations on a NFS client and server will cause server# mkdir a client# cd a server# mv a a.bak client# sleep 30 # (or whatever the dir attrcache timeout is) client# stat . stat: cannot stat `.': Stale NFS file handle Obviously, we should not be getting an ESTALE error back there since the inode still exists on the server. The problem is that the lookup code will call d_revalidate on the dentry that "." refers to, because NFS has FS_REVAL_DOT set. nfs_lookup_revalidate will see that the parent directory has changed and will try to reverify the dentry by redoing a LOOKUP. That of course fails, so the lookup code returns ESTALE. The problem here is that d_revalidate is really a bad fit for this case. What we really want to know at this point is whether the inode is still good or not, but we don't really care what name it goes by or whether the dcache is still valid. Add a new d_op->d_weak_revalidate operation and have complete_walk call that instead of d_revalidate. The intent there is to allow for a "weaker" d_revalidate that just checks to see whether the inode is still good. This is also gives us an opportunity to kill off the FS_REVAL_DOT special casing. [AV: changed method name, added note in porting, fixed confusion re having it possibly called from RCU mode (it won't be)] Cc: NeilBrown <neilb@suse.de> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-01-04f2fs: update f2fs document to reflect SIT/NAT layout correctlyHuajun Li
document to reflect the layout generated by mkfs.f2fs . Signed-off-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-21Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS update from Al Viro: "fscache fixes, ESTALE patchset, vmtruncate removal series, assorted misc stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (79 commits) vfs: make lremovexattr retry once on ESTALE error vfs: make removexattr retry once on ESTALE vfs: make llistxattr retry once on ESTALE error vfs: make listxattr retry once on ESTALE error vfs: make lgetxattr retry once on ESTALE vfs: make getxattr retry once on an ESTALE error vfs: allow lsetxattr() to retry once on ESTALE errors vfs: allow setxattr to retry once on ESTALE errors vfs: allow utimensat() calls to retry once on an ESTALE error vfs: fix user_statfs to retry once on ESTALE errors vfs: make fchownat retry once on ESTALE errors vfs: make fchmodat retry once on ESTALE errors vfs: have chroot retry once on ESTALE error vfs: have chdir retry lookup and call once on ESTALE error vfs: have faccessat retry once on an ESTALE error vfs: have do_sys_truncate retry once on an ESTALE error vfs: fix renameat to retry on ESTALE errors vfs: make do_unlinkat retry once on ESTALE errors vfs: make do_rmdir retry once on ESTALE errors vfs: add a flags argument to user_path_parent ...
2012-12-20Merge branch 'fscache' of ↵Al Viro
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into for-linus
2012-12-20documentation: drop vmtruncateMarco Stornelli
Removed vmtruncate Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20Merge branch 'for-3.8' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd update from Bruce Fields: "Included this time: - more nfsd containerization work from Stanislav Kinsbursky: we're not quite there yet, but should be by 3.9. - NFSv4.1 progress: implementation of basic backchannel security negotiation and the mandatory BACKCHANNEL_CTL operation. See http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues for remaining TODO's - Fixes for some bugs that could be triggered by unusual compounds. Our xdr code wasn't designed with v4 compounds in mind, and it shows. A more thorough rewrite is still a todo. - If you've ever seen "RPC: multiple fragments per record not supported" logged while using some sort of odd userland NFS client, that should now be fixed. - Further work from Jeff Layton on our mechanism for storing information about NFSv4 clients across reboots. - Further work from Bryan Schumaker on his fault-injection mechanism (which allows us to discard selective NFSv4 state, to excercise rarely-taken recovery code paths in the client.) - The usual mix of miscellaneous bugs and cleanup. Thanks to everyone who tested or contributed this cycle." * 'for-3.8' of git://linux-nfs.org/~bfields/linux: (111 commits) nfsd4: don't leave freed stateid hashed nfsd4: free_stateid can use the current stateid nfsd4: cleanup: replace rq_resused count by rq_next_page pointer nfsd: warn on odd reply state in nfsd_vfs_read nfsd4: fix oops on unusual readlike compound nfsd4: disable zero-copy on non-final read ops svcrpc: fix some printks NFSD: Correct the size calculation in fault_inject_write NFSD: Pass correct buffer size to rpc_ntop nfsd: pass proper net to nfsd_destroy() from NFSd kthreads nfsd: simplify service shutdown nfsd: replace boolean nfsd_up flag by users counter nfsd: simplify NFSv4 state init and shutdown nfsd: introduce helpers for generic resources init and shutdown nfsd: make NFSd service structure allocated per net nfsd: make NFSd service boot time per-net nfsd: per-net NFSd up flag introduced nfsd: move per-net startup code to separated function nfsd: pass net to __write_ports() and down nfsd: pass net to nfsd_set_nrthreads() ...
2012-12-20FS-Cache: Provide proper invalidationDavid Howells
Provide a proper invalidation method rather than relying on the netfs retiring the cookie it has and getting a new one. The problem with this is that isn't easy for the netfs to make sure that it has completed/cancelled all its outstanding storage and retrieval operations on the cookie it is retiring. Instead, have the cache provide an invalidation method that will cancel or wait for all currently outstanding operations before invalidating the cache, and will cause new operations to queue up behind that. Whilst invalidation is in progress, some requests will be rejected until the cache can stack a barrier on the operation queue to cause new operations to be deferred behind it. Signed-off-by: David Howells <dhowells@redhat.com>
2012-12-20FS-Cache: Fix operation state management and accountingDavid Howells
Fix the state management of internal fscache operations and the accounting of what operations are in what states. This is done by: (1) Give struct fscache_operation a enum variable that directly represents the state it's currently in, rather than spreading this knowledge over a bunch of flags, who's processing the operation at the moment and whether it is queued or not. This makes it easier to write assertions to check the state at various points and to prevent invalid state transitions. (2) Add an 'operation complete' state and supply a function to indicate the completion of an operation (fscache_op_complete()) and make things call it. The final call to fscache_put_operation() can then check that an op in the appropriate state (complete or cancelled). (3) Adjust the use of object->n_ops, ->n_in_progress, ->n_exclusive to better govern the state of an object: (a) The ->n_ops is now the number of extant operations on the object and is now decremented by fscache_put_operation() only. (b) The ->n_in_progress is simply the number of objects that have been taken off of the object's pending queue for the purposes of being run. This is decremented by fscache_op_complete() only. (c) The ->n_exclusive is the number of exclusive ops that have been submitted and queued or are in progress. It is decremented by fscache_op_complete() and by fscache_cancel_op(). fscache_put_operation() and fscache_operation_gc() now no longer try to clean up ->n_exclusive and ->n_in_progress. That was leading to double decrements against fscache_cancel_op(). fscache_cancel_op() now no longer decrements ->n_ops. That was leading to double decrements against fscache_put_operation(). fscache_submit_exclusive_op() now decides whether it has to queue an op based on ->n_in_progress being > 0 rather than ->n_ops > 0 as the latter will persist in being true even after all preceding operations have been cancelled or completed. Furthermore, if an object is active and there are runnable ops against it, there must be at least one op running. (4) Add a remaining-pages counter (n_pages) to struct fscache_retrieval and provide a function to record completion of the pages as they complete. When n_pages reaches 0, the operation is deemed to be complete and fscache_op_complete() is called. Add calls to fscache_retrieval_complete() anywhere we've finished with a page we've been given to read or allocate for. This includes places where we just return pages to the netfs for reading from the server and where accessing the cache fails and we discard the proposed netfs page. The bugs in the unfixed state management manifest themselves as oopses like the following where the operation completion gets out of sync with return of the cookie by the netfs. This is possible because the cache unlocks and returns all the netfs pages before recording its completion - which means that there's nothing to stop the netfs discarding them and returning the cookie. FS-Cache: Cookie 'NFS.fh' still has outstanding reads ------------[ cut here ]------------ kernel BUG at fs/fscache/cookie.c:519! invalid opcode: 0000 [#1] SMP CPU 1 Modules linked in: cachefiles nfs fscache auth_rpcgss nfs_acl lockd sunrpc Pid: 400, comm: kswapd0 Not tainted 3.1.0-rc7-fsdevel+ #1090 /DG965RY RIP: 0010:[<ffffffffa007050a>] [<ffffffffa007050a>] __fscache_relinquish_cookie+0x170/0x343 [fscache] RSP: 0018:ffff8800368cfb00 EFLAGS: 00010282 RAX: 000000000000003c RBX: ffff880023cc8790 RCX: 0000000000000000 RDX: 0000000000002f2e RSI: 0000000000000001 RDI: ffffffff813ab86c RBP: ffff8800368cfb50 R08: 0000000000000002 R09: 0000000000000000 R10: ffff88003a1b7890 R11: ffff88001df6e488 R12: ffff880023d8ed98 R13: ffff880023cc8798 R14: 0000000000000004 R15: ffff88003b8bf370 FS: 0000000000000000(0000) GS:ffff88003bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000000008ba008 CR3: 0000000023d93000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kswapd0 (pid: 400, threadinfo ffff8800368ce000, task ffff88003b8bf040) Stack: ffff88003b8bf040 ffff88001df6e528 ffff88001df6e528 ffffffffa00b46b0 ffff88003b8bf040 ffff88001df6e488 ffff88001df6e620 ffffffffa00b46b0 ffff88001ebd04c8 0000000000000004 ffff8800368cfb70 ffffffffa00b2c91 Call Trace: [<ffffffffa00b2c91>] nfs_fscache_release_inode_cookie+0x3b/0x47 [nfs] [<ffffffffa008f25f>] nfs_clear_inode+0x3c/0x41 [nfs] [<ffffffffa0090df1>] nfs4_evict_inode+0x2f/0x33 [nfs] [<ffffffff810d8d47>] evict+0xa1/0x15c [<ffffffff810d8e2e>] dispose_list+0x2c/0x38 [<ffffffff810d9ebd>] prune_icache_sb+0x28c/0x29b [<ffffffff810c56b7>] prune_super+0xd5/0x140 [<ffffffff8109b615>] shrink_slab+0x102/0x1ab [<ffffffff8109d690>] balance_pgdat+0x2f2/0x595 [<ffffffff8103e009>] ? process_timeout+0xb/0xb [<ffffffff8109dba3>] kswapd+0x270/0x289 [<ffffffff8104c5ea>] ? __init_waitqueue_head+0x46/0x46 [<ffffffff8109d933>] ? balance_pgdat+0x595/0x595 [<ffffffff8104bf7a>] kthread+0x7f/0x87 [<ffffffff813ad6b4>] kernel_thread_helper+0x4/0x10 [<ffffffff81026b98>] ? finish_task_switch+0x45/0xc0 [<ffffffff813abcdd>] ? retint_restore_args+0xe/0xe [<ffffffff8104befb>] ? __init_kthread_worker+0x53/0x53 [<ffffffff813ad6b0>] ? gs_change+0xb/0xb Signed-off-by: David Howells <dhowells@redhat.com>
2012-12-20Merge tag 'for-3.8-merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull new F2FS filesystem from Jaegeuk Kim: "Introduce a new file system, Flash-Friendly File System (F2FS), to Linux 3.8. Highlights: - Add initial f2fs source codes - Fix an endian conversion bug - Fix build failures on random configs - Fix the power-off-recovery routine - Minor cleanup, coding style, and typos patches" From the Kconfig help text: F2FS is based on Log-structured File System (LFS), which supports versatile "flash-friendly" features. The design has been focused on addressing the fundamental issues in LFS, which are snowball effect of wandering tree and high cleaning overhead. Since flash-based storages show different characteristics according to the internal geometry or flash memory management schemes aka FTL, F2FS and tools support various parameters not only for configuring on-disk layout, but also for selecting allocation and cleaning algorithms. and there's an article by Neil Brown about it on lwn.net: http://lwn.net/Articles/518988/ * tag 'for-3.8-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits) f2fs: fix tracking parent inode number f2fs: cleanup the f2fs_bio_alloc routine f2fs: introduce accessor to retrieve number of dentry slots f2fs: remove redundant call to f2fs_put_page in delete entry f2fs: make use of GFP_F2FS_ZERO for setting gfp_mask f2fs: rewrite f2fs_bio_alloc to make it simpler f2fs: fix a typo in f2fs documentation f2fs: remove unused variable f2fs: move error condition for mkdir at proper place f2fs: remove unneeded initialization f2fs: check read only condition before beginning write out f2fs: remove unneeded memset from init_once f2fs: show error in case of invalid mount arguments f2fs: fix the compiler warning for uninitialized use of variable f2fs: resolve build failures f2fs: adjust kernel coding style f2fs: fix endian conversion bugs reported by sparse f2fs: remove unneeded version.h header file from f2fs.h f2fs: update the f2fs document f2fs: update Kconfig and Makefile ...
2012-12-18docs: update documentation about /proc/<pid>/fdinfo/<fd> fanotify outputCyrill Gorcunov
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: James Bottomley <jbottomley@parallels.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Matthew Helsley <matt.helsley@gmail.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18docs: add documentation about /proc/<pid>/fdinfo/<fd> outputCyrill Gorcunov
[akpm@linux-foundation.org: tweak documentation] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: James Bottomley <jbottomley@parallels.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Matthew Helsley <matt.helsley@gmail.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18/proc/pid/status: add "Seccomp" fieldKees Cook
It is currently impossible to examine the state of seccomp for a given process. While attaching with gdb and attempting "call prctl(PR_GET_SECCOMP,...)" will work with some situations, it is not reliable. If the process is in seccomp mode 1, this query will kill the process (prctl not allowed), if the process is in mode 2 with prctl not allowed, it will similarly be killed, and in weird cases, if prctl is filtered to return errno 0, it can look like seccomp is disabled. When reviewing the state of running processes, there should be a way to externally examine the seccomp mode. ("Did this build of Chrome end up using seccomp?" "Did my distro ship ssh with seccomp enabled?") This adds the "Seccomp" line to /proc/$pid/status. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: James Morris <jmorris@namei.org> Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18procfs: add VmFlags field in smaps outputCyrill Gorcunov
During c/r sessions we've found that there is no way at the moment to fetch some VMA associated flags, such as mlock() and madvise(). This leads us to a problem -- we don't know if we should call for mlock() and/or madvise() after restore on the vma area we're bringing back to life. This patch intorduces a new field into "smaps" output called VmFlags, where all set flags associated with the particular VMA is shown as two letter mnemonics. [ Strictly speaking for c/r we only need mlock/madvise bits but it has been said that providing just a few flags looks somehow inconsistent. So all flags are here now. ] This feature is made available on CONFIG_CHECKPOINT_RESTORE=n kernels, as other applications may start to use these fields. The data is encoded in a somewhat awkward two letters mnemonic form, to encourage userspace to be prepared for fields being added or removed in the future. [a.p.zijlstra@chello.nl: props to use for_each_set_bit] [sfr@canb.auug.org.au: props to use array instead of struct] [akpm@linux-foundation.org: overall redesign and simplification] [akpm@linux-foundation.org: remove unneeded braces per sfr, avoid using bloaty for_each_set_bit()] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18fat: provide option for setting timezone offsetJan Kara
So far FAT either offsets time stamps by sys_tz.minuteswest or leaves them as they are (when tz=UTC mount option is used). However in some cases it is useful if one can specify time stamp offset on his own (e.g. when time zone of the camera connected is different from time zone of the computer, or when HW clock is in UTC and thus sys_tz.minuteswest == 0). So provide a mount option time_offset= which allows user to specify offset in minutes that should be applied to time stamps on the filesystem. akpm: this code would work incorrectly when used via `mount -o remount', because cached inodes would not be updated. But fatfs's fat_remount() is basically a no-op anyway. Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 update from Ted Ts'o: "There are two major features for this merge window. The first is inline data, which allows small files or directories to be stored in the in-inode extended attribute area. (This requires that the file system use inodes which are at least 256 bytes or larger; 128 byte inodes do not have any room for in-inode xattrs.) The second new feature is SEEK_HOLE/SEEK_DATA support. This is enabled by the extent status tree patches, and this infrastructure will be used to further optimize ext4 in the future. Beyond that, we have the usual collection of code cleanups and bug fixes." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (63 commits) ext4: zero out inline data using memset() instead of empty_zero_page ext4: ensure Inode flags consistency are checked at build time ext4: Remove CONFIG_EXT4_FS_XATTR ext4: remove unused variable from ext4_ext_in_cache() ext4: remove redundant initialization in ext4_fill_super() ext4: remove redundant code in ext4_alloc_inode() ext4: use sync_inode_metadata() when syncing inode metadata ext4: enable ext4 inline support ext4: let fallocate handle inline data correctly ext4: let ext4_truncate handle inline data correctly ext4: evict inline data out if we need to strore xattr in inode ext4: let fiemap work with inline data ext4: let ext4_rename handle inline dir ext4: let empty_dir handle inline dir ext4: let ext4_delete_entry() handle inline data ext4: make ext4_delete_entry generic ext4: let ext4_find_entry handle inline data ext4: create a new function search_dir ext4: let ext4_readdir handle inline data ext4: let add_dir_entry handle inline data properly ...
2012-12-14Merge branch 'core-efi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 EFI update from Peter Anvin: "EFI tree, from Matt Fleming. Most of the patches are the new efivarfs filesystem by Matt Garrett & co. The balance are support for EFI wallclock in the absence of a hardware-specific driver, and various fixes and cleanups." * 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) efivarfs: Make efivarfs_fill_super() static x86, efi: Check table header length in efi_bgrt_init() efivarfs: Use query_variable_info() to limit kmalloc() efivarfs: Fix return value of efivarfs_file_write() efivarfs: Return a consistent error when efivarfs_get_inode() fails efivarfs: Make 'datasize' unsigned long efivarfs: Add unique magic number efivarfs: Replace magic number with sizeof(attributes) efivarfs: Return an error if we fail to read a variable efi: Clarify GUID length calculations efivarfs: Implement exclusive access for {get,set}_variable efivarfs: efivarfs_fill_super() ensure we clean up correctly on error efivarfs: efivarfs_fill_super() ensure we free our temporary name efivarfs: efivarfs_fill_super() fix inode reference counts efivarfs: efivarfs_create() ensure we drop our reference on inode on error efivarfs: efivarfs_file_read ensure we free data in error paths x86-64/efi: Use EFI to deal with platform wall clock (again) x86/kernel: remove tboot 1:1 page table creation code x86, efi: 1:1 pagetable mapping for virtual EFI calls x86, mm: Include the entire kernel memory map in trampoline_pgd ...
2012-12-12Merge tag 'for-linus-v3.8-rc1' of git://oss.sgi.com/xfs/xfsLinus Torvalds
Pull xfs update from Ben Myers: "There is plenty going on, including the cleanup of xfssyncd, metadata verifiers, CRC infrastructure for the log, tracking of inodes with speculative allocation, a cleanup of xfs_fs_subr.c, fixes for XFS_IOC_ZERO_RANGE, and important fix related to log replay (only update the last_sync_lsn when a transaction completes), a fix for deadlock on AGF buffers, documentation and comment updates, and a few more cleanups and fixes. Details: - remove the xfssyncd mess - only update the last_sync_lsn when a transaction completes - zero allocation_args on the kernel stack - fix AGF/alloc workqueue deadlock - silence uninitialised f.file warning - Update inode alloc comments - Update mount options documentation - report projid32bit feature in geometry call - speculative preallocation inode tracking - fix attr tree double split corruption - fix broken error handling in xfs_vm_writepage - drop buffer io reference when a bad bio is built - add more attribute tree trace points - growfs infrastructure changes for 3.8 - fs/xfs/xfs_fs_subr.c die die die - add CRC infrastructure - add CRC checks to the log - Remove description of nodelaylog mount option from xfs.txt - inode allocation should use unmapped buffers - byte range granularity for XFS_IOC_ZERO_RANGE - fix direct IO nested transaction deadlock - fix stray dquot unlock when reclaiming dquots - fix sparse reported log CRC endian issue" Fix up trivial conflict in fs/xfs/xfs_fsops.c due to the same patch having been applied twice (commits eaef854335ce and 1375cb65e87b: "xfs: growfs: don't read garbage for new secondary superblocks") with later updates to the affected code in the XFS tree. * tag 'for-linus-v3.8-rc1' of git://oss.sgi.com/xfs/xfs: (78 commits) xfs: fix sparse reported log CRC endian issue xfs: fix stray dquot unlock when reclaiming dquots xfs: fix direct IO nested transaction deadlock. xfs: byte range granularity for XFS_IOC_ZERO_RANGE xfs: inode allocation should use unmapped buffers. xfs: Remove the description of nodelaylog mount option from xfs.txt xfs: add CRC checks to the log xfs: add CRC infrastructure xfs: convert buffer verifiers to an ops structure. xfs: connect up write verifiers to new buffers xfs: add pre-write metadata buffer verifier callbacks xfs: add buffer pre-write callback xfs: Add verifiers to dir2 data readahead. xfs: add xfs_da_node verification xfs: factor and verify attr leaf reads xfs: factor dir2 leaf read xfs: factor out dir2 data block reading xfs: factor dir2 free block reading xfs: verify dir2 block format buffers xfs: factor dir2 block read operations ...
2012-12-11f2fs: fix a typo in f2fs documentationHuajun Li
In f2fs_fs.h, one f2fs inode contains 923 data block pointers, while f2fs documentation says it is 929. Fix this inconsistence. Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
2012-12-11f2fs: update the f2fs documentJaegeuk Kim
I moved the f2fs-tools.git into kernel.org. And I added a new mailing list, linux-f2fs-devel@lists.sourceforge.net. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11f2fs: add documentJaegeuk Kim
This adds a document describing the mount options, proc entries, usage, and design of Flash-Friendly File System, namely F2FS. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-10ext4: Remove CONFIG_EXT4_FS_XATTRTao Ma
Ted has sent out a RFC about removing this feature. Eric and Jan confirmed that both RedHat and SUSE enable this feature in all their product. David also said that "As far as I know, it's enabled in all Android kernels that use ext4." So it seems OK for us. And what's more, as inline data depends its implementation on xattr, and to be frank, I don't run any test again inline data enabled while xattr disabled. So I think we should add inline data and remove this config option in the same release. [ The savings if you disable CONFIG_EXT4_FS_XATTR is only 27k, which isn't much in the grand scheme of things. Since no one seems to be testing this configuration except for some automated compile farms, on balance we are better removing this config option, and so that it is effectively always enabled. -- tytso ] Cc: David Brown <davidb@codeaurora.org> Cc: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-26xfs: Remove the description of nodelaylog mount option from xfs.txtSatoru Takeuchi
nodelaylog mount option is removed by commit 93b8a585. But there still be the description about it in the xfs document. This patch removes it. Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-26nfsd4: delay filling in write iovec array till after xdr decodingJ. Bruce Fields
Our server rejects compounds containing more than one write operation. It's unclear whether this is really permitted by the spec; with 4.0, it's possibly OK, with 4.1 (which has clearer limits on compound parameters), it's probably not OK. No client that we're aware of has ever done this, but in theory it could be useful. The source of the limitation: we need an array of iovecs to pass to the write operation. In the worst case that array of iovecs could have hundreds of elements (the maximum rwsize divided by the page size), so it's too big to put on the stack, or in each compound op. So we instead keep a single such array in the compound argument. We fill in that array at the time we decode the xdr operation. But we decode every op in the compound before executing any of them. So once we've used that array we can't decode another write. If we instead delay filling in that array till the time we actually perform the write, we can reuse it. Another option might be to switch to decoding compound ops one at a time. I considered doing that, but it has a number of other side effects, and I'd rather fix just this one problem for now. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-11-16mm, oom: reintroduce /proc/pid/oom_adjDavid Rientjes
This is mostly a revert of 01dc52ebdf47 ("oom: remove deprecated oom_adj") from Davidlohr Bueso. It reintroduces /proc/pid/oom_adj for backwards compatibility with earlier kernels. It simply scales the value linearly when /proc/pid/oom_score_adj is written. The major difference is that its scheduled removal is no longer included in Documentation/feature-removal-schedule.txt. We do warn users with a single printk, though, to suggest the more powerful and supported /proc/pid/oom_score_adj interface. Reported-by: Artem S. Tashkinov <t.artem@lycos.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-10nfsd4: update documentation on 4.1 progressJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-11-08nfsd4: implement backchannel_ctl operationJ. Bruce Fields
This operation is mandatory for servers to implement. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-11-02xfs: Update mount options documentationCarlos Maiolino
Once inode64 is the default allocation mode now, kernel documentation should be updated to match this behaviour. Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-30efivarfs: Add documentation for the EFI variable filesystemMatt Fleming
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2012-10-13Merge branch 'for-3.7' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd update from J Bruce Fields: "Another relatively quiet cycle. There was some progress on my remaining 4.1 todo's, but a couple of them were just of the form "check that we do X correctly", so didn't have much affect on the code. Other than that, a bunch of cleanup and some bugfixes (including an annoying NFSv4.0 state leak and a busy-loop in the server that could cause it to peg the CPU without making progress)." * 'for-3.7' of git://linux-nfs.org/~bfields/linux: (46 commits) UAPI: (Scripted) Disintegrate include/linux/sunrpc UAPI: (Scripted) Disintegrate include/linux/nfsd nfsd4: don't allow reclaims of expired clients nfsd4: remove redundant callback probe nfsd4: expire old client earlier nfsd4: separate session allocation and initialization nfsd4: clean up session allocation nfsd4: minor free_session cleanup nfsd4: new_conn_from_crses should only allocate nfsd4: separate connection allocation and initialization nfsd4: reject bad forechannel attrs earlier nfsd4: enforce per-client sessions/no-sessions distinction nfsd4: set cl_minorversion at create time nfsd4: don't pin clientids to pseudoflavors nfsd4: fix bind_conn_to_session xdr comment nfsd4: cast readlink() bug argument NFSD: pass null terminated buf to kstrtouint() nfsd: remove duplicate init in nfsd4_cb_recall nfsd4: eliminate redundant nfs4_free_stateid fs/nfsd/nfs4idmap.c: adjust inconsistent IS_ERR and PTR_ERR ...
2012-10-10Merge tag 'nfs-for-3.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates from Trond Myklebust: "Features include: - Remove CONFIG_EXPERIMENTAL dependency from NFSv4.1 Aside from the issues discussed at the LKS, distros are shipping NFSv4.1 with all the trimmings. - Fix fdatasync()/fsync() for the corner case of a server reboot. - NFSv4 OPEN access fix: finally distinguish correctly between open-for-read and open-for-execute permissions in all situations. - Ensure that the TCP socket is closed when we're in CLOSE_WAIT - More idmapper bugfixes - Lots of pNFS bugfixes and cleanups to remove unnecessary state and make the code easier to read. - In cases where a pNFS read or write fails, allow the client to resume trying layoutgets after two minutes of read/write- through-mds. - More net namespace fixes to the NFSv4 callback code. - More net namespace fixes to the NFSv3 locking code. - More NFSv4 migration preparatory patches. Including patches to detect network trunking in both NFSv4 and NFSv4.1 - pNFS block updates to optimise LAYOUTGET calls." * tag 'nfs-for-3.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (113 commits) pnfsblock: cleanup nfs4_blkdev_get NFS41: send real read size in layoutget NFS41: send real write size in layoutget NFS: track direct IO left bytes NFSv4.1: Cleanup ugliness in pnfs_layoutgets_blocked() NFSv4.1: Ensure that the layout sequence id stays 'close' to the current NFSv4.1: Deal with seqid wraparound in the pNFS return-on-close code NFSv4 set open access operation call flag in nfs4_init_opendata_res NFSv4.1: Remove the dependency on CONFIG_EXPERIMENTAL NFSv4 reduce attribute requests for open reclaim NFSv4: nfs4_open_done first must check that GETATTR decoded a file type NFSv4.1: Deal with wraparound when updating the layout "barrier" seqid NFSv4.1: Deal with wraparound issues when updating the layout stateid NFSv4.1: Always set the layout stateid if this is the first layoutget NFSv4.1: Fix another refcount issue in pnfs_find_alloc_layout NFSv4: don't put ACCESS in OPEN compound if O_EXCL NFSv4: don't check MAY_WRITE access bit in OPEN NFS: Set key construction data for the legacy upcall NFSv4.1: don't do two EXCHANGE_IDs on mount NFS: nfs41_walk_client_list(): re-lock before iterating ...
2012-10-09nfs: disintegrate UAPI for nfsJ. Bruce Fields
This is to complete part of the Userspace API (UAPI) disintegration for which the preparatory patches were pulled recently. After these patches, userspace headers will be segregated into: include/uapi/linux/.../foo.h for the userspace interface stuff, and: include/linux/.../foo.h for the strictly kernel internal stuff. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-10-09oom: remove deprecated oom_adjDavidlohr Bueso
The deprecated /proc/<pid>/oom_adj is scheduled for removal this month. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Acked-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-07Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The big new feature added this time is supporting online resizing using the meta_bg feature. This allows us to resize file systems which are greater than 16TB. In addition, the speed of online resizing has been improved in general. We also fix a number of races, some of which could lead to deadlocks, in ext4's Asynchronous I/O and online defrag support, thanks to good work by Dmitry Monakhov. There are also a large number of more minor bug fixes and cleanups from a number of other ext4 contributors, quite of few of which have submitted fixes for the first time." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (69 commits) ext4: fix ext4_flush_completed_IO wait semantics ext4: fix mtime update in nodelalloc mode ext4: fix ext_remove_space for punch_hole case ext4: punch_hole should wait for DIO writers ext4: serialize truncate with owerwrite DIO workers ext4: endless truncate due to nonlocked dio readers ext4: serialize unlocked dio reads with truncate ext4: serialize dio nonlocked reads with defrag workers ext4: completed_io locking cleanup ext4: fix unwritten counter leakage ext4: give i_aiodio_unwritten a more appropriate name ext4: ext4_inode_info diet ext4: convert to use leXX_add_cpu() ext4: ext4_bread usage audit fs: reserve fallocate flag codepoint ext4: remove redundant offset check in mext_check_arguments() ext4: don't clear orphan list on ro mount with errors jbd2: fix assertion failure in commit code due to lacking transaction credits ext4: release donor reference when EXT4_IOC_MOVE_EXT ioctl fails ext4: enable FITRIM ioctl on bigalloc file system ...
2012-10-03Merge tag 'jfs-3.7' of git://github.com/kleikamp/linux-shaggyLinus Torvalds
Pull JFS update from Dave Kleikamp: "JFS TRIM support and some minor fixes" * tag 'jfs-3.7' of git://github.com/kleikamp/linux-shaggy: jfs: Fix do_div precision in commit b40c2e66 JFS: use list_move instead of list_del/list_add jfs: Remove obsolete email address fs/jfs: TRIM support for JFS Filesystem
2012-10-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking changes from David Miller: 1) GRE now works over ipv6, from Dmitry Kozlov. 2) Make SCTP more network namespace aware, from Eric Biederman. 3) TEAM driver now works with non-ethernet devices, from Jiri Pirko. 4) Make openvswitch network namespace aware, from Pravin B Shelar. 5) IPV6 NAT implementation, from Patrick McHardy. 6) Server side support for TCP Fast Open, from Jerry Chu and others. 7) Packet BPF filter supports MOD and XOR, from Eric Dumazet and Daniel Borkmann. 8) Increate the loopback default MTU to 64K, from Eric Dumazet. 9) Use a per-task rather than per-socket page fragment allocator for outgoing networking traffic. This benefits processes that have very many mostly idle sockets, which is quite common. From Eric Dumazet. 10) Use up to 32K for page fragment allocations, with fallbacks to smaller sizes when higher order page allocations fail. Benefits are a) less segments for driver to process b) less calls to page allocator c) less waste of space. From Eric Dumazet. 11) Allow GRO to be used on GRE tunnels, from Eric Dumazet. 12) VXLAN device driver, one way to handle VLAN issues such as the limitation of 4096 VLAN IDs yet still have some level of isolation. From Stephen Hemminger. 13) As usual there is a large boatload of driver changes, with the scale perhaps tilted towards the wireless side this time around. Fix up various fairly trivial conflicts, mostly caused by the user namespace changes. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1012 commits) hyperv: Add buffer for extended info after the RNDIS response message. hyperv: Report actual status in receive completion packet hyperv: Remove extra allocated space for recv_pkt_list elements hyperv: Fix page buffer handling in rndis_filter_send_request() hyperv: Fix the missing return value in rndis_filter_set_packet_filter() hyperv: Fix the max_xfer_size in RNDIS initialization vxlan: put UDP socket in correct namespace vxlan: Depend on CONFIG_INET sfc: Fix the reported priorities of different filter types sfc: Remove EFX_FILTER_FLAG_RX_OVERRIDE_IP sfc: Fix loopback self-test with separate_tx_channels=1 sfc: Fix MCDI structure field lookup sfc: Add parentheses around use of bitfield macro arguments sfc: Fix null function pointer in efx_sriov_channel_type vxlan: virtual extensible lan igmp: export symbol ip_mc_leave_group netlink: add attributes to fdb interface tg3: unconditionally select HWMON support when tg3 is enabled. Revert "net: ti cpsw ethernet: allow reading phy interface mode from DT" gre: fix sparse warning ...
2012-10-01NFS: Add nfs4_unique_id boot parameterChuck Lever
An optional boot parameter is introduced to allow client administrators to specify a string that the Linux NFS client can insert into its nfs_client_id4 id string, to make it both more globally unique, and to ensure that it doesn't change even if the client's nodename changes. If this boot parameter is not specified, the client's nodename is used, as before. Client installation procedures can create a unique string (typically, a UUID) which remains unchanged during the lifetime of that client instance. This works just like creating a UUID for the label of the system's root and boot volumes. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-21ipconfig: add nameserver IPs to kernel-parameter ip=Christoph Fritz
On small systems (e.g. embedded ones) IP addresses are often configured by bootloaders and get assigned to kernel via parameter "ip=". If set to "ip=dhcp", even nameserver entries from DHCP daemons are handled. These entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf. To configure nameservers for networks without DHCP, this patch adds option <dns0-ip> and <dns1-ip> to kernel-parameter 'ip='. Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com> Tested-by: Jan Weitzel <j.weitzel@phytec.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-17jfs: Remove obsolete email addressDave Kleikamp
The MAINTAINERS file suffices. Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
2012-09-17fs/jfs: TRIM support for JFS FilesystemTino Reichardt
This patch adds support for the two linux interfaces of the discard/TRIM command for SSD devices and sparse/thinly-provisioned LUNs. JFS will support batched discard via FITRIM ioctl and online discard with the discard mount option. Signed-off-by: Tino Reichardt <list-jfs@mcmilk.de> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
2012-08-27debugfs: more tightly restrict default mount modeKees Cook
Since the debugfs is mostly only used by root, make the default mount mode 0700. Most system owners do not need a more permissive value, but they can choose to weaken the restrictions via their fstab. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-21Documentation: update mount option in filesystem/vfat.txtNamjae Jeon
Update two mount options(discard, nfs) in vfat.txt. Signed-off-by: Namjae Jeon <linkinjeon@gmail.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21nfsd: document kernel interfaces for nfsd configurationJ. Bruce Fields
These are only needed by nfs-utils. But I needed to remind myself how they worked recently and thought this might be helpful. It's short and incomplete for now as I was only interested in startup, shutdown, and configuration of listening sockets. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-17ext4: add max_dir_size_kb mount optionTheodore Ts'o
Very large directories can cause significant performance problems, or perhaps even invoke the OOM killer, if the process is running in a highly constrained memory environment (whether it is VM's with a small amount of memory or in a small memory cgroup). So it is useful, in cloud server/data center environments, to be able to set a filesystem-wide cap on the maximum size of a directory, to ensure that directories never get larger than a sane size. We do this via a new mount option, max_dir_size_kb. If there is an attempt to grow the directory larger than max_dir_size_kb, the system call will return ENOSPC instead. Google-Bug-Id: 6863013 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-08-03Documentation: get rid of write_superArtem Bityutskiy
The '->write_super' superblock method is gone, and this patch removes all the references to 'write_super' from various pieces of the kernel documentation. Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
2012-08-01locks: remove unused lm_release_privateJ. Bruce Fields
In commit 3b6e2723f32d ("locks: prevent side-effects of locks_release_private before file_lock is initialized") we removed the last user of lm_release_private without removing the field itself. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-01mm: add support for a filesystem to activate swap files and use direct_IO ↵Mel Gorman
for writing swap pages Currently swapfiles are managed entirely by the core VM by using ->bmap to allocate space and write to the blocks directly. This effectively ensures that the underlying blocks are allocated and avoids the need for the swap subsystem to locate what physical blocks store offsets within a file. If the swap subsystem is to use the filesystem information to locate the blocks, it is critical that information such as block groups, block bitmaps and the block descriptor table that map the swap file were resident in memory. This patch adds address_space_operations that the VM can call when activating or deactivating swap backed by a file. int swap_activate(struct file *); int swap_deactivate(struct file *); The ->swap_activate() method is used to communicate to the file that the VM relies on it, and the address_space should take adequate measures such as reserving space in the underlying device, reserving memory for mempools and pinning information such as the block descriptor table in memory. The ->swap_deactivate() method is called on sys_swapoff() if ->swap_activate() returned success. After a successful swapfile ->swap_activate, the swapfile is marked SWP_FILE and swapper_space.a_ops will proxy to sis->swap_file->f_mappings->a_ops using ->direct_io to write swapcache pages and ->readpage to read. It is perfectly possible that direct_IO be used to read the swap pages but it is an unnecessary complication. Similarly, it is possible that ->writepage be used instead of direct_io to write the pages but filesystem developers have stated that calling writepage from the VM is undesirable for a variety of reasons and using direct_IO opens up the possibility of writing back batches of swap pages in the future. [a.p.zijlstra@chello.nl: Original patch] Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Eric B Munson <emunson@mgebm.net> Cc: Eric Paris <eparis@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Xiaotian Feng <dfeng@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31Documentation: Correct s_umount state for freeze_fs/unfreeze_fsValerie Aurora
freeze_fs/unfreeze_fs ops are called with s_umount held for write, not read. Signed-off-by: Valerie Aurora <val@vaaconsulting.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>