[PATCH V19 19/19] Btrfs: subpage-blocksize: Disable compression
From: Chandan Rajendra <hidden>
Date: 2016-06-14 07:12:43
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
The subpage-blocksize patchset does not yet support compression. Hence, the kernel might crash when executing compression code in subpage-blocksize scenario. This commit disables enabling compression feature during 'mount' and also when the user invokes 'chattr +c <filename>' command. Signed-off-by: Chandan Rajendra <redacted> --- fs/btrfs/ioctl.c | 8 +++++++- fs/btrfs/super.c | 20 ++++++++++++++++++++ 2 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 77c2aa8..c4fd80e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c@@ -322,6 +322,11 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg) } else if (flags & FS_COMPR_FL) { const char *comp; + if (root->sectorsize < PAGE_SIZE) { + ret = -EINVAL; + goto out_drop; + } + ip->flags |= BTRFS_INODE_COMPRESS; ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
@@ -1342,7 +1347,8 @@ int btrfs_defrag_file(struct inode *inode, struct file *file, return -EINVAL; if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { - if (range->compress_type > BTRFS_COMPRESS_TYPES) + if ((range->compress_type > BTRFS_COMPRESS_TYPES) + || (root->sectorsize < PAGE_SIZE)) return -EINVAL; if (range->compress_type) compress_type = range->compress_type;
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index ae30f52..70c0ee3 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c@@ -368,6 +368,17 @@ static const match_table_t tokens = { {Opt_err, NULL}, }; +static int can_enable_compression(struct btrfs_fs_info *fs_info) +{ + if (btrfs_super_sectorsize(fs_info->super_copy) < PAGE_SIZE) { + btrfs_err(fs_info, + "Compression is not supported for subpage-blocksize"); + return 0; + } + + return 1; +} + /* * Regular mount options parser. Everything that is needed only when * reading in a new superblock is parsed here.
@@ -477,6 +488,10 @@ int btrfs_parse_options(struct btrfs_root *root, char *options, if (token == Opt_compress || token == Opt_compress_force || strcmp(args[0].from, "zlib") == 0) { + if (!can_enable_compression(info)) { + ret = -EINVAL; + goto out; + } compress_type = "zlib"; info->compress_type = BTRFS_COMPRESS_ZLIB; btrfs_set_opt(info->mount_opt, COMPRESS);
@@ -484,6 +499,10 @@ int btrfs_parse_options(struct btrfs_root *root, char *options, btrfs_clear_opt(info->mount_opt, NODATASUM); no_compress = 0; } else if (strcmp(args[0].from, "lzo") == 0) { + if (!can_enable_compression(info)) { + ret = -EINVAL; + goto out; + } compress_type = "lzo"; info->compress_type = BTRFS_COMPRESS_LZO; btrfs_set_opt(info->mount_opt, COMPRESS);
@@ -806,6 +825,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options, break; } } + check: /* * Extra check for current option against current flag
--
2.1.0