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 <chan...@linux.vnet.ibm.com> --- fs/btrfs/ioctl.c | 8 +++++++- fs/btrfs/super.c | 19 +++++++++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 0fdc0a0..862d97b 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 73a1d8d..3a2e9d7 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -392,6 +392,17 @@ 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. @@ -502,6 +513,10 @@ 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); @@ -509,6 +524,10 @@ 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); -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html