From 2eaa055fab4e3127c9f572fda1b710cbb2acdf1c Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Fri, 15 Nov 2013 15:33:55 -0500 Subject: btrfs: add ioctls to query/change feature bits online There are some feature bits that require no offline setup and can be enabled online. I've only reviewed extended irefs, but there will probably be more. We introduce three new ioctls: - BTRFS_IOC_GET_SUPPORTED_FEATURES: query the kernel for supported features. - BTRFS_IOC_GET_FEATURES: query the kernel for enabled features on a per-fs basis, as well as querying for which features are changeable with mounted. - BTRFS_IOC_SET_FEATURES: change features on a per-fs basis. We introduce two new masks per feature set (_SAFE_SET and _SAFE_CLEAR) that allow us to define which features are safe to change at runtime. The failure modes for BTRFS_IOC_SET_FEATURES are as follows: - Enabling a completely unsupported feature: warns and returns -ENOTSUPP - Enabling a feature that can only be done offline: warns and returns -EPERM Signed-off-by: Jeff Mahoney Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- include/uapi/linux/btrfs.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index 45e618921c61..b4d69092fbdb 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -184,6 +184,12 @@ struct btrfs_ioctl_fs_info_args { __u64 reserved[124]; /* pad to 1k */ }; +struct btrfs_ioctl_feature_flags { + __u64 compat_flags; + __u64 compat_ro_flags; + __u64 incompat_flags; +}; + /* balance control ioctl modes */ #define BTRFS_BALANCE_CTL_PAUSE 1 #define BTRFS_BALANCE_CTL_CANCEL 2 @@ -606,5 +612,11 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) struct btrfs_ioctl_dev_replace_args) #define BTRFS_IOC_FILE_EXTENT_SAME _IOWR(BTRFS_IOCTL_MAGIC, 54, \ struct btrfs_ioctl_same_args) +#define BTRFS_IOC_GET_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \ + struct btrfs_ioctl_feature_flags) +#define BTRFS_IOC_SET_FEATURES _IOW(BTRFS_IOCTL_MAGIC, 57, \ + struct btrfs_ioctl_feature_flags[2]) +#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \ + struct btrfs_ioctl_feature_flags[3]) #endif /* _UAPI_LINUX_BTRFS_H */ -- cgit v1.2.3 From 01e219e8069516cdb98594d417b8bb8d906ed30d Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Fri, 1 Nov 2013 13:07:03 -0400 Subject: btrfs: add ioctl to export size of global metadata reservation btrfs filesystem df output will show the size of the metadata space and how much of it is used, and the user assumes that the difference is all usable space. Since that's not actually the case due to the global metadata reservation, we should provide the full picture to the user. This patch adds an ioctl that exports the size of the global metadata reservation so that btrfs filesystem df can report it. Signed-off-by: Jeff Mahoney Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- include/uapi/linux/btrfs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index b4d69092fbdb..1b8a0f4c9590 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -558,6 +558,7 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) #define BTRFS_IOC_DEFAULT_SUBVOL _IOW(BTRFS_IOCTL_MAGIC, 19, __u64) #define BTRFS_IOC_SPACE_INFO _IOWR(BTRFS_IOCTL_MAGIC, 20, \ struct btrfs_ioctl_space_args) +#define BTRFS_IOC_GLOBAL_RSV _IOR(BTRFS_IOCTL_MAGIC, 20, __u64) #define BTRFS_IOC_START_SYNC _IOR(BTRFS_IOCTL_MAGIC, 24, __u64) #define BTRFS_IOC_WAIT_SYNC _IOW(BTRFS_IOCTL_MAGIC, 22, __u64) #define BTRFS_IOC_SNAP_CREATE_V2 _IOW(BTRFS_IOCTL_MAGIC, 23, \ -- cgit v1.2.3 From 63541927c8d11d2686778b1e8ec71c14b4fd53e4 Mon Sep 17 00:00:00 2001 From: Filipe David Borba Manana Date: Tue, 7 Jan 2014 11:47:46 +0000 Subject: Btrfs: add support for inode properties 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 --- include/uapi/linux/xattr.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/xattr.h b/include/uapi/linux/xattr.h index e4629b93bdd6..40bbc04b6f81 100644 --- a/include/uapi/linux/xattr.h +++ b/include/uapi/linux/xattr.h @@ -20,6 +20,9 @@ #define XATTR_MAC_OSX_PREFIX "osx." #define XATTR_MAC_OSX_PREFIX_LEN (sizeof(XATTR_MAC_OSX_PREFIX) - 1) +#define XATTR_BTRFS_PREFIX "btrfs." +#define XATTR_BTRFS_PREFIX_LEN (sizeof(XATTR_BTRFS_PREFIX) - 1) + #define XATTR_SECURITY_PREFIX "security." #define XATTR_SECURITY_PREFIX_LEN (sizeof(XATTR_SECURITY_PREFIX) - 1) -- cgit v1.2.3