@@ -652,6 +652,7 @@ enum {
/* ioctl codes 19--39 are reserved for fscrypt */
#define EXT4_IOC_CLEAR_ES_CACHE _IO('f', 40)
#define EXT4_IOC_GETSTATE _IOW('f', 41, __u32)
+#define EXT4_IOC_GET_ES_CACHE _IOWR('f', 42, struct fiemap)
#define EXT4_IOC_FSGETXATTR FS_IOC_FSGETXATTR
#define EXT4_IOC_FSSETXATTR FS_IOC_FSSETXATTR
@@ -692,6 +693,12 @@ enum {
#define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
#endif
+/*
+ * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
+ * It indicates that the entry in extent status cache is for a hole.
+ */
+#define EXT4_FIEMAP_EXTENT_HOLE 0x08000000
+
/* Max physical block we can address w/o extents */
#define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
@@ -3258,6 +3265,9 @@ extern int ext4_ext_check_inode(struct inode *inode);
extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
__u64 start, __u64 len);
+extern int ext4_get_es_cache(struct inode *inode,
+ struct fiemap_extent_info *fieinfo,
+ __u64 start, __u64 len);
extern int ext4_ext_precache(struct inode *inode);
extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
@@ -2315,6 +2315,52 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
return err;
}
+static int ext4_fill_es_cache_info(struct inode *inode,
+ ext4_lblk_t block, ext4_lblk_t num,
+ struct fiemap_extent_info *fieinfo)
+{
+ ext4_lblk_t next, end = block + num - 1;
+ struct extent_status es;
+ unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
+ unsigned int flags;
+ int err;
+
+ while (block <= end) {
+ next = 0;
+ flags = 0;
+ if (!ext4_es_lookup_extent(inode, block, &next, &es))
+ break;
+ if (ext4_es_is_unwritten(&es))
+ flags |= FIEMAP_EXTENT_UNWRITTEN;
+ if (ext4_es_is_delayed(&es))
+ flags |= (FIEMAP_EXTENT_DELALLOC |
+ FIEMAP_EXTENT_UNKNOWN);
+ if (ext4_es_is_hole(&es))
+ flags |= EXT4_FIEMAP_EXTENT_HOLE;
+ if (next == 0)
+ flags |= FIEMAP_EXTENT_LAST;
+ if (flags & (FIEMAP_EXTENT_DELALLOC|
+ EXT4_FIEMAP_EXTENT_HOLE))
+ es.es_pblk = 0;
+ else
+ es.es_pblk = ext4_es_pblock(&es);
+ err = fiemap_fill_next_extent(fieinfo,
+ (__u64)es.es_lblk << blksize_bits,
+ (__u64)es.es_pblk << blksize_bits,
+ (__u64)es.es_len << blksize_bits,
+ flags);
+ if (next == 0)
+ break;
+ block = next;
+ if (err < 0)
+ return err;
+ if (err == 1)
+ return 0;
+ }
+ return 0;
+}
+
+
/*
* ext4_ext_determine_hole - determine hole around given block
* @inode: inode we lookup in
@@ -5017,8 +5063,6 @@ static int ext4_find_delayed_extent(struct inode *inode,
return next_del;
}
-/* fiemap flags we can handle specified here */
-#define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
static int ext4_xattr_fiemap(struct inode *inode,
struct fiemap_extent_info *fieinfo)
@@ -5055,10 +5099,16 @@ static int ext4_xattr_fiemap(struct inode *inode,
return (error < 0 ? error : 0);
}
-int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
- __u64 start, __u64 len)
+static int _ext4_fiemap(struct inode *inode,
+ struct fiemap_extent_info *fieinfo,
+ __u64 start, __u64 len,
+ int (*fill)(struct inode *, ext4_lblk_t,
+ ext4_lblk_t,
+ struct fiemap_extent_info *))
{
ext4_lblk_t start_blk;
+ u32 ext4_fiemap_flags = FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR;
+
int error = 0;
if (ext4_has_inline_data(inode)) {
@@ -5075,14 +5125,18 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
error = ext4_ext_precache(inode);
if (error)
return error;
+ fieinfo->fi_flags &= ~FIEMAP_FLAG_CACHE;
}
/* fallback to generic here if not in extents fmt */
- if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
+ if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) &&
+ fill == ext4_fill_fiemap_extents)
return generic_block_fiemap(inode, fieinfo, start, len,
ext4_get_block);
- if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
+ if (fill == ext4_fill_es_cache_info)
+ ext4_fiemap_flags &= FIEMAP_FLAG_XATTR;
+ if (fiemap_check_flags(fieinfo, ext4_fiemap_flags))
return -EBADR;
if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
@@ -5101,12 +5155,36 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
* Walk the extent tree gathering extent information
* and pushing extents back to the user.
*/
- error = ext4_fill_fiemap_extents(inode, start_blk,
- len_blks, fieinfo);
+ error = fill(inode, start_blk, len_blks, fieinfo);
}
return error;
}
+int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+ __u64 start, __u64 len)
+{
+ return _ext4_fiemap(inode, fieinfo, start, len,
+ ext4_fill_fiemap_extents);
+}
+
+int ext4_get_es_cache(struct inode *inode, struct fiemap_extent_info *fieinfo,
+ __u64 start, __u64 len)
+{
+ if (ext4_has_inline_data(inode)) {
+ int has_inline;
+
+ down_read(&EXT4_I(inode)->xattr_sem);
+ has_inline = ext4_has_inline_data(inode);
+ up_read(&EXT4_I(inode)->xattr_sem);
+ if (has_inline)
+ return 0;
+ }
+
+ return _ext4_fiemap(inode, fieinfo, start, len,
+ ext4_fill_es_cache_info);
+}
+
+
/*
* ext4_access_path:
* Function to access the path buffer for marking it dirty.
@@ -899,6 +899,7 @@ void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
* Return: 1 on found, 0 on not
*/
int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
+ ext4_lblk_t *next_lblk,
struct extent_status *es)
{
struct ext4_es_tree *tree;
@@ -948,6 +949,15 @@ int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
if (!ext4_es_is_referenced(es1))
ext4_es_set_referenced(es1);
stats->es_stats_cache_hits++;
+ if (next_lblk) {
+ node = rb_next(&es1->rb_node);
+ if (node) {
+ es1 = rb_entry(node, struct extent_status,
+ rb_node);
+ *next_lblk = es1->es_lblk;
+ } else
+ *next_lblk = 0;
+ }
} else {
stats->es_stats_cache_misses++;
}
@@ -140,6 +140,7 @@ extern void ext4_es_find_extent_range(struct inode *inode,
ext4_lblk_t lblk, ext4_lblk_t end,
struct extent_status *es);
extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
+ ext4_lblk_t *next_lblk,
struct extent_status *es);
extern bool ext4_es_scan_range(struct inode *inode,
int (*matching_fn)(struct extent_status *es),
@@ -527,7 +527,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
return -EFSCORRUPTED;
/* Lookup extent status tree firstly */
- if (ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
+ if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) {
if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {
map->m_pblk = ext4_es_pblock(&es) +
map->m_lblk - es.es_lblk;
@@ -695,7 +695,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
* extent status tree.
*/
if ((flags & EXT4_GET_BLOCKS_PRE_IO) &&
- ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
+ ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) {
if (ext4_es_is_written(&es))
goto out_sem;
}
@@ -1868,7 +1868,7 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
(unsigned long) map->m_lblk);
/* Lookup extent status tree firstly */
- if (ext4_es_lookup_extent(inode, iblock, &es)) {
+ if (ext4_es_lookup_extent(inode, iblock, NULL, &es)) {
if (ext4_es_is_hole(&es)) {
retval = 0;
down_read(&EXT4_I(inode)->i_data_sem);
@@ -745,6 +745,74 @@ static void ext4_fill_fsxattr(struct inode *inode, struct fsxattr *fa)
fa->fsx_projid = from_kprojid(&init_user_ns, ei->i_projid);
}
+/* copied from fs/ioctl.c */
+static int fiemap_check_ranges(struct super_block *sb,
+ u64 start, u64 len, u64 *new_len)
+{
+ u64 maxbytes = (u64) sb->s_maxbytes;
+
+ *new_len = len;
+
+ if (len == 0)
+ return -EINVAL;
+
+ if (start > maxbytes)
+ return -EFBIG;
+
+ /*
+ * Shrink request scope to what the fs can actually handle.
+ */
+ if (len > maxbytes || (maxbytes - len) < start)
+ *new_len = maxbytes - start;
+
+ return 0;
+}
+
+/* So that the fiemap access checks can't overflow on 32 bit machines. */
+#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
+
+static int ext4_ioctl_get_es_cache(struct file *filp, unsigned long arg)
+{
+ struct fiemap fiemap;
+ struct fiemap __user *ufiemap = (struct fiemap __user *) arg;
+ struct fiemap_extent_info fieinfo = { 0, };
+ struct inode *inode = file_inode(filp);
+ struct super_block *sb = inode->i_sb;
+ u64 len;
+ int error;
+
+ if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
+ return -EFAULT;
+
+ if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
+ return -EINVAL;
+
+ error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length,
+ &len);
+ if (error)
+ return error;
+
+ fieinfo.fi_flags = fiemap.fm_flags;
+ fieinfo.fi_extents_max = fiemap.fm_extent_count;
+ fieinfo.fi_extents_start = ufiemap->fm_extents;
+
+ if (fiemap.fm_extent_count != 0 &&
+ !access_ok(fieinfo.fi_extents_start,
+ fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
+ return -EFAULT;
+
+ if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
+ filemap_write_and_wait(inode->i_mapping);
+
+ error = ext4_get_es_cache(inode, &fieinfo, fiemap.fm_start, len);
+ fiemap.fm_flags = fieinfo.fi_flags;
+ fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
+ if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
+ error = -EFAULT;
+
+ return error;
+}
+
long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct inode *inode = file_inode(filp);
@@ -1139,6 +1207,9 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return put_user(state, (__u32 __user *) arg);
}
+ case EXT4_IOC_GET_ES_CACHE:
+ return ext4_ioctl_get_es_cache(filp, arg);
+
case EXT4_IOC_FSGETXATTR:
{
struct fsxattr fa;
@@ -1259,6 +1330,7 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case FS_IOC_GETFSMAP:
case EXT4_IOC_CLEAR_ES_CACHE:
case EXT4_IOC_GETSTATE:
+ case EXT4_IOC_GET_ES_CACHE:
break;
default:
return -ENOIOCTLCMD;
For debugging reasons, it's useful to know the contents of the extent cache. Since the extent cache contains much of what is in the fiemap ioctl, use an fiemap-style interface to return this information. Signed-off-by: Theodore Ts'o <tytso@mit.edu> --- fs/ext4/ext4.h | 10 +++++ fs/ext4/extents.c | 94 ++++++++++++++++++++++++++++++++++++---- fs/ext4/extents_status.c | 10 +++++ fs/ext4/extents_status.h | 1 + fs/ext4/inode.c | 6 +-- fs/ext4/ioctl.c | 72 ++++++++++++++++++++++++++++++ 6 files changed, 182 insertions(+), 11 deletions(-)