diff options
author | Andreas Dilger <andreas.dilger@intel.com> | 2016-12-14 13:24:44 +0100 |
---|---|---|
committer | Sasha Levin <alexander.levin@verizon.com> | 2016-12-23 08:56:34 -0500 |
commit | 1b364dc9edba5ad079a43853fd319a3a255f5b29 (patch) | |
tree | edf594e9af81cb2807db4537de221005b0ba97df /fs | |
parent | 9a66bc6ee0f9908ba98a7d19b94d49ec231ab0e1 (diff) |
xattr: Option to disable meta-data block cache
mbcache provides absolutely no value for Lustre xattrs (because
they are unique and cannot be shared between files) and as we can
see it has a noticable overhead in some cases. In the past there
was a CONFIG_MBCACHE option that would allow it to be disabled,
but this was removed in newer kernels, so we will need to patch
ldiskfs to fix this.
References: <https://bugzilla.kernel.org/show_bug.cgi?id=107301>
References: <https://git.hpdd.intel.com/fs/lustre-release.git/blob_plain/HEAD:/ldiskfs/kernel_patches/patches/rhel7/ext4-disable-mb-cache.patch>
References: CVE-2015-8952
On 13.12.2016 at 15:58 Ben Hutchings wrote:
> I decided not to apply this as it's a userland ABI extension that we
> would then need to carry indefinitely.
Signed-off-by: Philipp Hahn <hahn@univention.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ext4/ext4.h | 1 | ||||
-rw-r--r-- | fs/ext4/super.c | 3 | ||||
-rw-r--r-- | fs/ext4/xattr.c | 32 |
3 files changed, 24 insertions, 12 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 15213a567301..145d6ba4117d 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1008,6 +1008,7 @@ struct ext4_inode_info { /* * Mount flags set via mount options or defaults */ +#define EXT4_MOUNT_NO_MBCACHE 0x00001 /* Disable mbcache */ #define EXT4_MOUNT_GRPID 0x00004 /* Create files with directory's group */ #define EXT4_MOUNT_DEBUG 0x00008 /* Some debugging messages */ #define EXT4_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */ diff --git a/fs/ext4/super.c b/fs/ext4/super.c index afb3eb3e8b0f..4723d8b02747 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1144,6 +1144,7 @@ enum { Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity, Opt_inode_readahead_blks, Opt_journal_ioprio, Opt_dioread_nolock, Opt_dioread_lock, + Opt_no_mbcache, Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable, Opt_max_dir_size_kb, Opt_nojournal_checksum, }; @@ -1222,6 +1223,7 @@ static const match_table_t tokens = { {Opt_discard, "discard"}, {Opt_nodiscard, "nodiscard"}, {Opt_init_itable, "init_itable=%u"}, + {Opt_no_mbcache, "no_mbcache"}, {Opt_init_itable, "init_itable"}, {Opt_noinit_itable, "noinit_itable"}, {Opt_max_dir_size_kb, "max_dir_size_kb=%u"}, @@ -1385,6 +1387,7 @@ static const struct mount_opts { {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET}, {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR}, {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR}, + {Opt_no_mbcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET}, {Opt_commit, 0, MOPT_GTE0}, {Opt_max_batch_time, 0, MOPT_GTE0}, {Opt_min_batch_time, 0, MOPT_GTE0}, diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index 16e28c08d1e8..cdc26e54400f 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -80,7 +80,7 @@ # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) #endif -static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *); +static void ext4_xattr_cache_insert(struct inode *, struct buffer_head *); static struct buffer_head *ext4_xattr_cache_find(struct inode *, struct ext4_xattr_header *, struct mb_cache_entry **); @@ -278,7 +278,6 @@ ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, struct ext4_xattr_entry *entry; size_t size; int error; - struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", name_index, name, buffer, (long)buffer_size); @@ -300,7 +299,7 @@ bad_block: error = -EIO; goto cleanup; } - ext4_xattr_cache_insert(ext4_mb_cache, bh); + ext4_xattr_cache_insert(inode, bh); entry = BFIRST(bh); error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); if (error == -EIO) @@ -426,7 +425,6 @@ ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) struct inode *inode = d_inode(dentry); struct buffer_head *bh = NULL; int error; - struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); ea_idebug(inode, "buffer=%p, buffer_size=%ld", buffer, (long)buffer_size); @@ -448,7 +446,7 @@ ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) error = -EIO; goto cleanup; } - ext4_xattr_cache_insert(ext4_mb_cache, bh); + ext4_xattr_cache_insert(inode, bh); error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); cleanup: @@ -547,7 +545,8 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode, int error = 0; struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); - ce = mb_cache_entry_get(ext4_mb_cache, bh->b_bdev, bh->b_blocknr); + if (!test_opt(inode->i_sb, NO_MBCACHE)) + ce = mb_cache_entry_get(ext4_mb_cache, bh->b_bdev, bh->b_blocknr); BUFFER_TRACE(bh, "get_write_access"); error = ext4_journal_get_write_access(handle, bh); if (error) @@ -788,8 +787,9 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, if (i->value && i->value_len > sb->s_blocksize) return -ENOSPC; if (s->base) { - ce = mb_cache_entry_get(ext4_mb_cache, bs->bh->b_bdev, - bs->bh->b_blocknr); + if (!test_opt(inode->i_sb, NO_MBCACHE)) + ce = mb_cache_entry_get(ext4_mb_cache, bs->bh->b_bdev, + bs->bh->b_blocknr); BUFFER_TRACE(bs->bh, "get_write_access"); error = ext4_journal_get_write_access(handle, bs->bh); if (error) @@ -807,7 +807,7 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, if (!IS_LAST_ENTRY(s->first)) ext4_xattr_rehash(header(s->base), s->here); - ext4_xattr_cache_insert(ext4_mb_cache, + ext4_xattr_cache_insert(inode, bs->bh); } unlock_buffer(bs->bh); @@ -892,7 +892,8 @@ inserted: if (error) goto cleanup_dquot; } - mb_cache_entry_release(ce); + if (ce) + mb_cache_entry_release(ce); ce = NULL; } else if (bs->bh && s->base == bs->bh->b_data) { /* We were modifying this block in-place. */ @@ -939,7 +940,7 @@ getblk_failed: memcpy(new_bh->b_data, s->base, new_bh->b_size); set_buffer_uptodate(new_bh); unlock_buffer(new_bh); - ext4_xattr_cache_insert(ext4_mb_cache, new_bh); + ext4_xattr_cache_insert(inode, new_bh); error = ext4_handle_dirty_xattr_block(handle, inode, new_bh); if (error) @@ -1529,12 +1530,17 @@ ext4_xattr_put_super(struct super_block *sb) * Returns 0, or a negative error number on failure. */ static void -ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) +ext4_xattr_cache_insert(struct inode *inode, struct buffer_head *bh) { + struct super_block *sb = inode->i_sb; + struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); __u32 hash = le32_to_cpu(BHDR(bh)->h_hash); struct mb_cache_entry *ce; int error; + if (test_opt(sb, NO_MBCACHE)) + return; + ce = mb_cache_entry_alloc(ext4_mb_cache, GFP_NOFS); if (!ce) { ea_bdebug(bh, "out of memory"); @@ -1609,6 +1615,8 @@ ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, struct mb_cache_entry *ce; struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); + if (test_opt(inode->i_sb, NO_MBCACHE)) + return NULL; if (!header->h_hash) return NULL; /* never share */ ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); |