kernel.git/fs/btrfs/super.c, branch linux-3.14.y

btrfs: cleanup orphans while looking up default subvolume

2015-06-23T00:01:24Z

commit 727b9784b6085c99c2f836bf4fcc2848dc9cf904 upstream. Orphans in the fs tree are cleaned up via open_ctree and subvolume orphans are cleaned via btrfs_lookup_dentry -- except when a default subvolume is in use. The name for the default subvolume uses a manual lookup that doesn't trigger orphan cleanup and needs to trigger it manually as well. This doesn't apply to the remount case since the subvolumes are cleaned up by walking the root radix tree. Signed-off-by: Jeff Mahoney Reviewed-by: David Sterba Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman

Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol

2014-02-14T21:44:32Z

A user was running into errors from an NFS export of a subvolume that had a default subvol set. When we mount a default subvol we will use d_obtain_alias() to find an existing dentry for the subvolume in the case that the root subvol has already been mounted, or a dummy one is allocated in the case that the root subvol has not already been mounted. This allows us to connect the dentry later on if we wander into the path. However if we don't ever wander into the path we will keep DCACHE_DISCONNECTED set for a long time, which angers NFS. It doesn't appear to cause any problems but it is annoying nonetheless, so simply unset DCACHE_DISCONNECTED in the get_default_root case and switch btrfs_lookup() to use d_materialise_unique() instead which will make everything play nicely together and reconnect stuff if we wander into the defaul subvol path from a different way. With this patch I'm no longer getting the NFS errors when exporting a volume that has been mounted with a default subvol set. Thanks, cc: bfields@fieldses.org cc: ebiederm@xmission.com Signed-off-by: Josef Bacik Acked-by: "Eric W. Biederman" Signed-off-by: Chris Mason

Btrfs: fix max_inline mount option

2014-02-14T21:44:32Z

Currently, the only mount option for max_inline that has any effect is max_inline=0. Any other value that is supplied to max_inline will be adjusted to a minimum of 4k. Since max_inline has an effective maximum of ~3900 bytes due to page size limitations, the current behaviour only has meaning for max_inline=0. This patch will allow the the max_inline mount option to accept non-zero values as indicated in the documentation. Signed-off-by: Mitch Harder Signed-off-by: Chris Mason

Btrfs: use late_initcall instead of module_init

2014-02-03T17:01:28Z

It seems that when init_btrfs_fs() is called, crc32c/crc32c-intel might not always be already initialized, which results in the call to crypto_alloc_shash() returning -ENOENT, as experienced by Ahmet who reported this. Therefore make sure init_btrfs_fs() is called after crc32c is initialized (which is at initialization level 6, module_init), by using late_initcall (which is at initialization level 7) instead of module_init for btrfs. Reported-and-Tested-by: Ahmet Inan Signed-off-by: Filipe David Borba Manana Signed-off-by: Chris Mason

btrfs: Cleanup the btrfs_parse_options for remount.

2014-01-28T21:20:34Z

Since remount will pending the new mount options to the original mount options, which will make btrfs_parse_options check the old options then new options, causing some stupid output like "enabling XXX" following by "disable XXX". This patch will add extra check before every btrfs_info to skip the output from old options checking. Signed-off-by: Qu Wenruo Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

btrfs: Add noinode_cache mount option

2014-01-28T21:20:33Z

Add noinode_cache mount option for btrfs. Since inode map cache involves all the btrfs_find_free_ino/return_ino things and if just trigger the mount_opt, an inode number get from inode map cache will not returned to inode map cache. To keep the find and return inode both in the same behavior, a new bit in mount_opt, CHANGE_INODE_CACHE, is introduced for this idea. CHANGE_INODE_CACHE is set/cleared in remounting, and the original INODE_MAP_CACHE is set/cleared according to CHANGE_INODE_CACHE after a success transaction. Since find/return inode is all done between btrfs_start_transaction and btrfs_commit_transaction, this will keep consistent behavior. Also noinode_cache mount option will not stop the caching_kthread. Cc: David Sterba Signed-off-by: Miao Xie Signed-off-by: Qu Wenruo Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

Btrfs: fix btrfs boot when compiled as built-in

2014-01-28T21:20:31Z

After the change titled "Btrfs: add support for inode properties", if btrfs was built-in the kernel (i.e. not as a module), it would cause a kernel panic, as reported recently by Fengguang: [ 2.024722] BUG: unable to handle kernel NULL pointer dereference at (null) [ 2.027814] IP: [] crc32c+0xc/0x6b [ 2.028684] PGD 0 [ 2.028684] Oops: 0000 [#1] SMP [ 2.028684] Modules linked in: [ 2.028684] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc7-04795-ga7b57c2 #1 [ 2.028684] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 2.028684] task: ffff88000edba100 ti: ffff88000edd6000 task.ti: ffff88000edd6000 [ 2.028684] RIP: 0010:[] [] crc32c+0xc/0x6b [ 2.028684] RSP: 0000:ffff88000edd7e58 EFLAGS: 00010246 [ 2.028684] RAX: 0000000000000000 RBX: ffffffff82295550 RCX: 0000000000000000 [ 2.028684] RDX: 0000000000000011 RSI: ffffffff81efe393 RDI: 00000000fffffffe [ 2.028684] RBP: ffff88000edd7e60 R08: 0000000000000003 R09: 0000000000015d20 [ 2.028684] R10: ffffffff81ef225e R11: ffffffff811b0222 R12: ffffffffffffffff [ 2.028684] R13: 0000000000000239 R14: 0000000000000000 R15: 0000000000000000 [ 2.028684] FS: 0000000000000000(0000) GS:ffff88000fa00000(0000) knlGS:0000000000000000 [ 2.028684] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 2.028684] CR2: 0000000000000000 CR3: 000000000220c000 CR4: 00000000000006f0 [ 2.028684] Stack: [ 2.028684] ffffffff82295550 ffff88000edd7e80 ffffffff8238af62 ffffffff8238ac05 [ 2.028684] 0000000000000000 ffff88000edd7e98 ffffffff8238ac0f ffffffff8238ac05 [ 2.028684] ffff88000edd7f08 ffffffff810002ba ffff88000edd7f00 ffffffff810e2404 [ 2.028684] Call Trace: [ 2.028684] [] btrfs_props_init+0x4f/0x96 [ 2.028684] [] ? ftrace_define_fields_btrfs_space_reservation+0x145/0x145 [ 2.028684] [] init_btrfs_fs+0xa/0xf0 [ 2.028684] [] ? ftrace_define_fields_btrfs_space_reservation+0x145/0x145 [ 2.028684] [] do_one_initcall+0xa4/0x13a [ 2.028684] [] ? parse_args+0x25f/0x33d [ 2.028684] [] kernel_init_freeable+0x1aa/0x230 [ 2.028684] [] ? do_early_param+0x88/0x88 [ 2.028684] [] ? rest_init+0x89/0x89 [ 2.028684] [] kernel_init+0xe/0x109 The issue here is that the initialization function of btrfs (super.c:init_btrfs_fs) started using crc32c (from lib/libcrc32c.c). But when it needs to call crc32c (as part of the properties initialization routine), the libcrc32c is not yet initialized, so crc32c derreferenced a NULL pointer (lib/libcrc32c.c:tfm), causing the kernel panic on boot. The approach to fix this is to use crypto component directly to use its crc32c (which is basically what lib/libcrc32c.c is, a wrapper around crypto). This is what ext4 is doing as well, it uses crypto directly to get crc32c functionality. Verified this works both when btrfs is built-in and when it's loadable kernel module. Signed-off-by: Filipe David Borba Manana Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

Btrfs: add support for inode properties

2014-01-28T21:20:24Z

This change adds infrastructure to allow for generic properties for inodes. Properties are name/value pairs that can be associated with inodes for different purposes. They are stored as xattrs with the prefix "btrfs." Properties can be inherited - this means when a directory inode has inheritable properties set, these are added to new inodes created under that directory. Further, subvolumes can also have properties associated with them, and they can be inherited from their parent subvolume. Naturally, directory properties have priority over subvolume properties (in practice a subvolume property is just a regular property associated with the root inode, objectid 256, of the subvolume's fs tree). This change also adds one specific property implementation, named "compression", whose values can be "lzo" or "zlib" and it's an inheritable property. The corresponding changes to btrfs-progs were also implemented. A patch with xfstests for this feature will follow once there's agreement on this change/feature. Further, the script at the bottom of this commit message was used to do some benchmarks to measure any performance penalties of this feature. Basically the tests correspond to: Test 1 - create a filesystem and mount it with compress-force=lzo, then sequentially create N files of 64Kb each, measure how long it took to create the files, unmount the filesystem, mount the filesystem and perform an 'ls -lha' against the test directory holding the N files, and report the time the command took. Test 2 - create a filesystem and don't use any compression option when mounting it - instead set the compression property of the subvolume's root to 'lzo'. Then create N files of 64Kb, and report the time it took. The unmount the filesystem, mount it again and perform an 'ls -lha' like in the former test. This means every single file ends up with a property (xattr) associated to it. Test 3 - same as test 2, but uses 4 properties - 3 are duplicates of the compression property, have no real effect other than adding more work when inheriting properties and taking more btree leaf space. Test 4 - same as test 3 but with 10 properties per file. Results (in seconds, and averages of 5 runs each), for different N numbers of files follow. * Without properties (test 1) file creation time ls -lha time 10 000 files 3.49 0.76 100 000 files 47.19 8.37 1 000 000 files 518.51 107.06 * With 1 property (compression property set to lzo - test 2) file creation time ls -lha time 10 000 files 3.63 0.93 100 000 files 48.56 9.74 1 000 000 files 537.72 125.11 * With 4 properties (test 3) file creation time ls -lha time 10 000 files 3.94 1.20 100 000 files 52.14 11.48 1 000 000 files 572.70 142.13 * With 10 properties (test 4) file creation time ls -lha time 10 000 files 4.61 1.35 100 000 files 58.86 13.83 1 000 000 files 656.01 177.61 The increased latencies with properties are essencialy because of: *) When creating an inode, we now synchronously write 1 more item (an xattr item) for each property inherited from the parent dir (or subvolume). This could be done in an asynchronous way such as we do for dir intex items (delayed-inode.c), which could help reduce the file creation latency; *) With properties, we now have larger fs trees. For this particular test each xattr item uses 75 bytes of leaf space in the fs tree. This could be less by using a new item for xattr items, instead of the current btrfs_dir_item, since we could cut the 'location' and 'type' fields (saving 18 bytes) and maybe 'transid' too (saving a total of 26 bytes per xattr item) from the btrfs_dir_item type. Also tried batching the xattr insertions (ignoring proper hash collision handling, since it didn't exist) when creating files that inherit properties from their parent inode/subvolume, but the end results were (surprisingly) essentially the same. Test script: $ cat test.pl #!/usr/bin/perl -w use strict; use Time::HiRes qw(time); use constant NUM_FILES => 10_000; use constant FILE_SIZES => (64 * 1024); use constant DEV => '/dev/sdb4'; use constant MNT_POINT => '/home/fdmanana/btrfs-tests/dev'; use constant TEST_DIR => (MNT_POINT . '/testdir'); system("mkfs.btrfs", "-l", "16384", "-f", DEV) == 0 or die "mkfs.btrfs failed!"; # following line for testing without properties #system("mount", "-o", "compress-force=lzo", DEV, MNT_POINT) == 0 or die "mount failed!"; # following 2 lines for testing with properties system("mount", DEV, MNT_POINT) == 0 or die "mount failed!"; system("btrfs", "prop", "set", MNT_POINT, "compression", "lzo") == 0 or die "set prop failed!"; system("mkdir", TEST_DIR) == 0 or die "mkdir failed!"; my ($t1, $t2); $t1 = time(); for (my $i = 1; $i <= NUM_FILES; $i++) { my $p = TEST_DIR . '/file_' . $i; open(my $f, '>', $p) or die "Error opening file!"; $f->autoflush(1); for (my $j = 0; $j < FILE_SIZES; $j += 4096) { print $f ('A' x 4096) or die "Error writing to file!"; } close($f); } $t2 = time(); print "Time to create " . NUM_FILES . ": " . ($t2 - $t1) . " seconds.\n"; system("umount", DEV) == 0 or die "umount failed!"; system("mount", DEV, MNT_POINT) == 0 or die "mount failed!"; $t1 = time(); system("bash -c 'ls -lha " . TEST_DIR . " > /dev/null'") == 0 or die "ls failed!"; $t2 = time(); print "Time to ls -lha all files: " . ($t2 - $t1) . " seconds.\n"; system("umount", DEV) == 0 or die "umount failed!"; Signed-off-by: Filipe David Borba Manana Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

btrfs: Add treelog mount option.

2014-01-28T21:20:20Z

Add treelog mount option to enable tree log with remount option. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: Josef Bacik Signed-off-by: Chris Mason

btrfs: Add datasum mount option.

2014-01-28T21:20:20Z

Add datasum mount option to enable checksum with remount option. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: Josef Bacik Signed-off-by: Chris Mason