OpenCloudOS-Kernel/fs
Darrick J. Wong 2c813ad66a xfs: support btrees with overlapping intervals for keys
On a filesystem with both reflink and reverse mapping enabled, it's
possible to have multiple rmap records referring to the same blocks on
disk.  When overlapping intervals are possible, querying a classic
btree to find all records intersecting a given interval is inefficient
because we cannot use the left side of the search interval to filter
out non-matching records the same way that we can use the existing
btree key to filter out records coming after the right side of the
search interval.  This will become important once we want to use the
rmap btree to rebuild BMBTs, or implement the (future) fsmap ioctl.

(For the non-overlapping case, we can perform such queries trivially
by starting at the left side of the interval and walking the tree
until we pass the right side.)

Therefore, extend the btree code to come closer to supporting
intervals as a first-class record attribute.  This involves widening
the btree node's key space to store both the lowest key reachable via
the node pointer (as the btree does now) and the highest key reachable
via the same pointer and teaching the btree modifying functions to
keep the highest-key records up to date.

This behavior can be turned on via a new btree ops flag so that btrees
that cannot store overlapping intervals don't pay the overhead costs
in terms of extra code and disk format changes.

When we're deleting a record in a btree that supports overlapped
interval records and the deletion results in two btree blocks being
joined, we defer updating the high/low keys until after all possible
joining (at higher levels in the tree) have finished.  At this point,
the btree pointers at all levels have been updated to remove the empty
blocks and we can update the low and high keys.

When we're doing this, we must be careful to update the keys of all
node pointers up to the root instead of stopping at the first set of
keys that don't need updating.  This is because it's possible for a
single deletion to cause joining of multiple levels of tree, and so
we need to update everything going back to the root.

The diff_two_keys functions return < 0, 0, or > 0 if key1 is less than,
equal to, or greater than key2, respectively.  This is consistent
with the rest of the kernel and the C library.

In btree_updkeys(), we need to evaluate the force_all parameter before
running the key diff to avoid reading uninitialized memory when we're
forcing a key update.  This happens when we've allocated an empty slot
at level N + 1 to point to a new block at level N and we're in the
process of filling out the new keys.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-08-03 11:08:36 +10:00
..
9p switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
adfs fs/adfs/adfs.h: tidy up comments 2016-01-20 17:09:18 -08:00
affs affs: fix remount failure when there are no options changed 2016-05-28 16:50:24 -07:00
afs remove lots of IS_ERR_VALUE abuses 2016-05-27 15:26:11 -07:00
autofs4 dcache_{readdir,dir_lseek}() users: switch to ->iterate_shared 2016-05-02 19:49:32 -04:00
befs fs/befs/io.c:befs_bread(): remove unneeded initialization to NULL 2016-05-23 17:04:14 -07:00
bfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
cachefiles mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
cifs switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
coda introduce a parallel variant of ->iterate() 2016-05-02 19:49:29 -04:00
configfs configfs_readdir(): make safe under shared lock 2016-05-09 11:41:13 -04:00
cramfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
crypto fscrypto/f2fs: allow fs-specific key prefix for fs encryption 2016-05-07 10:32:33 -07:00
debugfs Merge 4.6-rc4 into driver-core-next 2016-04-19 04:28:28 +09:00
devpts devpts: more pty driver interface cleanups 2016-04-26 15:47:32 -07:00
dlm mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
ecryptfs switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
efivarfs fs/efivarfs/inode.c: use generic UUID library 2016-05-20 17:58:30 -07:00
efs fs/efs/super.c: fix return value 2016-05-20 17:58:30 -07:00
exofs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2016-05-17 17:05:30 -07:00
exportfs introduce a parallel variant of ->iterate() 2016-05-02 19:49:29 -04:00
ext2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
ext4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
f2fs switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
fat Merge branch 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-17 15:05:23 -07:00
freevxfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
fscache mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
fuse switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
gfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
hfs switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
hfsplus switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
hostfs hostfs: switch to ->iterate_shared() 2016-05-12 19:49:30 -04:00
hpfs hpfs: implement the show_options method 2016-05-28 16:50:24 -07:00
hugetlbfs mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage 2016-04-04 10:41:08 -07:00
isofs Merge branch 'ovl-fixes' into for-linus 2016-05-11 00:00:29 -04:00
jbd2 Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
jffs2 switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
jfs switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
kernfs switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
lockd lockd: constify nlmsvc_binding structure 2016-01-07 10:10:50 -05:00
logfs logfs: no need to lock directory in lseek 2016-05-09 11:42:19 -04:00
minix simple local filesystems: switch to ->iterate_shared() 2016-05-02 19:49:32 -04:00
ncpfs mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
nfs nfs: fix anonymous member initializer build failure with older compilers 2016-05-27 17:20:27 -07:00
nfs_common
nfsd fs: move struct iomap from exportfs.h to a separate header 2016-06-21 09:22:39 +10:00
nilfs2 nilfs2: fix block comments 2016-05-23 17:04:14 -07:00
nls
notify fsnotify: avoid spurious EMFILE errors from inotify_init() 2016-05-19 19:12:14 -07:00
ntfs fs: simplify the generic_write_sync prototype 2016-05-01 19:58:39 -04:00
ocfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
omfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
openpromfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
orangefs switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
overlayfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
proc mm, proc: make clear_refs killable 2016-05-23 17:04:14 -07:00
pstore mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
qnx4 more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
qnx6 more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
quota fs/quota: use nla_put_u64_64bit() 2016-04-26 12:00:48 -04:00
ramfs tmpfs/ramfs: fix VM_MAYSHARE mappings for NOMMU 2016-05-20 17:58:30 -07:00
reiserfs switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
romfs romfs, squashfs: switch to ->iterate_shared() 2016-05-09 11:41:15 -04:00
squashfs romfs, squashfs: switch to ->iterate_shared() 2016-05-09 11:41:15 -04:00
sysfs
sysv simple local filesystems: switch to ->iterate_shared() 2016-05-02 19:49:32 -04:00
tracefs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ubifs This pull request contains mostly cleanups and minor 2016-05-27 18:49:29 -07:00
udf Merge branch 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-17 15:05:23 -07:00
ufs simple local filesystems: switch to ->iterate_shared() 2016-05-02 19:49:32 -04:00
xfs xfs: support btrees with overlapping intervals for keys 2016-08-03 11:08:36 +10:00
Kconfig fs: introduce iomap infrastructure 2016-06-21 09:23:11 +10:00
Kconfig.binfmt ELF/MIPS build fix 2016-05-23 17:04:14 -07:00
Makefile fs: introduce iomap infrastructure 2016-06-21 09:23:11 +10:00
aio.c aio: make aio_setup_ring killable 2016-05-23 17:04:14 -07:00
anon_inodes.c
attr.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
bad_inode.c switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
binfmt_aout.c fs: fix binfmt_aout.c build error 2016-05-28 16:34:59 -07:00
binfmt_elf.c mm: remove more IS_ERR_VALUE abuses 2016-05-27 15:57:31 -07:00
binfmt_elf_fdpic.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-18 11:51:59 -07:00
binfmt_em86.c
binfmt_flat.c remove lots of IS_ERR_VALUE abuses 2016-05-27 15:26:11 -07:00
binfmt_misc.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
binfmt_script.c
block_dev.c DAX error handling for 4.7 2016-05-26 19:34:26 -07:00
buffer.c fs: introduce iomap infrastructure 2016-06-21 09:23:11 +10:00
char_dev.c chrdev: emit a warning when we go below dynamic major range 2016-03-29 10:11:44 -07:00
compat.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
compat_binfmt_elf.c
compat_ioctl.c Merge 4.5-rc4 into char-misc-next 2016-02-14 14:25:59 -08:00
coredump.c coredump: make coredump_wait wait for mmap_sem for write killable 2016-05-23 17:04:14 -07:00
dax.c Filesystem DAX locking for 4.7 2016-05-26 20:00:28 -07:00
dcache.c Merge branch 'hash' of git://ftp.sciencehorizons.net/linux 2016-05-28 16:15:25 -07:00
dcookies.c
direct-io.c direct-io: fix direct write stale data exposure from concurrent buffered read 2016-05-27 14:49:37 -07:00
drop_caches.c
eventfd.c eventfd: document lockless access in eventfd_poll 2016-03-22 15:36:02 -07:00
eventpoll.c fs: poll/select/recvmmsg: use timespec64 for timeout events 2016-05-19 19:12:14 -07:00
exec.c exec: make exec path waiting for mmap_sem killable 2016-05-23 17:04:14 -07:00
fcntl.c fcntl: allow to set O_DIRECT flag on pipe 2016-01-09 02:55:37 -05:00
fhandle.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-03-22 15:36:02 -07:00
file.c give readdir(2)/getdents(2)/etc. uniform exclusion with lseek() 2016-05-02 19:49:28 -04:00
file_table.c
filesystems.c find_filesystem(): simplify comparison 2016-01-19 12:02:23 -05:00
fs-writeback.c mm,writeback: don't use memory reserves for wb_start_writeback 2016-05-20 17:58:30 -07:00
fs_pin.c
fs_struct.c
inode.c parallel lookups: actual switch to rwsem 2016-05-02 19:49:28 -04:00
internal.h fs: introduce iomap infrastructure 2016-06-21 09:23:11 +10:00
ioctl.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
iomap.c fs: iomap based fiemap implementation 2016-06-21 09:38:45 +10:00
libfs.c switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
locks.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
mbcache.c mbcache: add reusable flag to cache entries 2016-02-22 22:44:04 -05:00
mount.h
mpage.c mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage 2016-04-04 10:41:08 -07:00
namei.c hash_string: Fix zero-length case for !DCACHE_WORD_ACCESS 2016-05-29 07:33:47 -07:00
namespace.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
no-block.c
nsfs.c
open.c Merge branch 'work.const-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-17 14:41:03 -07:00
pipe.c mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
pnode.c propogate_mnt: Handle the first propogated copy being a slave 2016-05-05 09:54:45 -05:00
pnode.h
posix_acl.c switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
proc_namespace.c vfs: show_vfsstat: do not ignore errors from show_devname method 2016-03-16 13:09:08 -04:00
read_write.c Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-18 11:46:23 -07:00
readdir.c restore killability of old mutex_lock_killable(&inode->i_mutex) users 2016-05-26 00:13:25 -04:00
select.c fs: poll/select/recvmmsg: use timespec64 for timeout events 2016-05-19 19:12:14 -07:00
seq_file.c Make file credentials available to the seqfile interfaces 2016-04-14 12:56:09 -07:00
signalfd.c
splice.c Merge branch 'ovl-fixes' into for-linus 2016-05-11 00:00:29 -04:00
stack.c
stat.c fs/stat.c: drop the last new_valid_dev check 2016-01-16 11:17:23 -08:00
statfs.c
super.c Merge branch 'master' into for-next 2016-04-18 11:18:55 +02:00
sync.c mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
timerfd.c timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper 2016-01-17 11:13:55 +01:00
userfaultfd.c userfaultfd: don't pin the user memory in userfaultfd_file_create() 2016-05-20 17:58:30 -07:00
utimes.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
xattr.c switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00