1 A large part of this code is from the generic VFS code in fs/ioctl.c in the
4 Index: linux-2.6.16.60-0.23/fs/ext3/ioctl.c
5 ===================================================================
6 --- linux-2.6.16.60-0.23.orig/fs/ext3/ioctl.c
7 +++ linux-2.6.16.60-0.23/fs/ext3/ioctl.c
9 #include <linux/time.h>
10 #include <asm/uaccess.h>
11 #include <linux/namei.h>
14 +/* So that the fiemap access checks can't overflow on 32 bit machines. */
15 +#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
18 + * fiemap_fill_next_extent - Fiemap helper function
19 + * @fieinfo: Fiemap context passed into ->fiemap
20 + * @logical: Extent logical start offset, in bytes
21 + * @phys: Extent physical start offset, in bytes
22 + * @len: Extent length, in bytes
23 + * @flags: FIEMAP_EXTENT flags that describe this extent
24 + * @lun: LUN on which this extent resides
26 + * Called from file system ->fiemap callback. Will populate extent
27 + * info as passed in via arguments and copy to user memory. On
28 + * success, extent count on fieinfo is incremented.
30 + * Returns 0 on success, -errno on error, 1 if this was the last
31 + * extent that will fit in user array.
33 +#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
34 +#define SET_NO_DIRECT_FLAGS (FIEMAP_EXTENT_DATA_COMPRESSED \
35 + |FIEMAP_EXTENT_DATA_ENCRYPTED \
37 +#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
38 +int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
39 + u64 phys, u64 len, u32 flags, dev_t dev)
41 + struct fiemap_extent extent = { 0 };
42 + struct fiemap_extent *dest = fieinfo->fi_extents_start;
44 + /* only count the extents */
45 + if (fieinfo->fi_extents_max == 0) {
46 + fieinfo->fi_extents_mapped++;
47 + return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
50 + if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
53 + if (flags & SET_UNKNOWN_FLAGS)
54 + flags |= FIEMAP_EXTENT_UNKNOWN;
55 + if (flags & SET_NO_DIRECT_FLAGS)
56 + flags |= FIEMAP_EXTENT_NO_DIRECT;
57 + if (flags & SET_NOT_ALIGNED_FLAGS)
58 + flags |= FIEMAP_EXTENT_NOT_ALIGNED;
60 + extent.fe_logical = logical;
61 + extent.fe_physical = phys;
62 + extent.fe_length = len;
63 + extent.fe_flags = flags;
64 + extent.fe_device = new_encode_dev(dev);
66 + dest += fieinfo->fi_extents_mapped;
67 + if (copy_to_user(dest, &extent, sizeof(extent)))
70 + fieinfo->fi_extents_mapped++;
71 + if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
74 + return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
77 +static int fiemap_check_ranges(struct super_block *sb,
78 + u64 start, u64 len, u64 *new_len)
85 + if (start > sb->s_maxbytes)
89 + * Shrink request scope to what the fs can actually handle.
91 + if ((len > sb->s_maxbytes) ||
92 + (sb->s_maxbytes - len) < start)
93 + *new_len = sb->s_maxbytes - start;
99 + * fiemap_check_flags - check validity of requested flags for fiemap
100 + * @fieinfo: Fiemap context passed into ->fiemap
101 + * @fs_flags: Set of fiemap flags that the file system understands
103 + * Called from file system ->fiemap callback. This will compute the
104 + * intersection of valid fiemap flags and those that the fs supports. That
105 + * value is then compared against the user supplied flags. In case of bad user
106 + * flags, the invalid values will be written into the fieinfo structure, and
107 + * -EBADR is returned, which tells ioctl_fiemap() to return those values to
108 + * userspace. For this reason, a return code of -EBADR should be preserved.
110 + * Returns 0 on success, -EBADR on bad flags.
112 +int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags)
114 + u32 incompat_flags;
116 + incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags);
117 + if (incompat_flags) {
118 + fieinfo->fi_flags = incompat_flags;
125 +int ioctl_fiemap(struct inode *inode, struct file *filp, unsigned long arg)
127 + struct fiemap fiemap;
129 + struct fiemap_extent_info fieinfo = {0, };
130 + struct super_block *sb = inode->i_sb;
133 + if (copy_from_user(&fiemap, (struct fiemap __user *) arg,
134 + sizeof(struct fiemap)))
137 + if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
140 + error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length,
145 + fieinfo.fi_flags = fiemap.fm_flags;
146 + fieinfo.fi_extents_max = fiemap.fm_extent_count;
147 + fieinfo.fi_extents_start = (struct fiemap_extent *)(arg + sizeof(fiemap));
149 + if (fiemap.fm_extent_count != 0 &&
150 + !access_ok(VERIFY_WRITE, (void *)arg,
151 + offsetof(typeof(fiemap), fm_extents[fiemap.fm_extent_count])))
154 + if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
155 + filemap_write_and_wait(inode->i_mapping);
157 + error = ext3_fiemap(inode, &fieinfo, fiemap.fm_start, len);
158 + fiemap.fm_flags = fieinfo.fi_flags;
159 + fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
160 + if (copy_to_user((char *)arg, &fiemap, sizeof(fiemap)))
166 int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
168 @@ -262,7 +414,9 @@ flags_err:
173 + case EXT3_IOC_FIEMAP: {
174 + return ioctl_fiemap(inode, filp, arg);
179 Index: linux-2.6.16.60-0.23/include/linux/ext3_fs.h
180 ===================================================================
181 --- linux-2.6.16.60-0.23.orig/include/linux/ext3_fs.h
182 +++ linux-2.6.16.60-0.23/include/linux/ext3_fs.h
183 @@ -260,15 +260,19 @@ struct ext3_new_group_data {
184 #define EXT3_IOC_SETFLAGS _IOW('f', 2, long)
185 #define EXT3_IOC_GETVERSION _IOR('f', 3, long)
186 #define EXT3_IOC_SETVERSION _IOW('f', 4, long)
187 +#define EXT3_IOC_GETRSVSZ _IOR('f', 5, long)
188 +#define EXT3_IOC_SETRSVSZ _IOW('f', 6, long)
189 #define EXT3_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
190 #define EXT3_IOC_GROUP_ADD _IOW('f', 8,struct ext3_new_group_input)
191 +#define EXT3_IOC_FIEMAP _IOWR('f', 10, struct fiemap)
192 #define EXT3_IOC_GETVERSION_OLD _IOR('v', 1, long)
193 #define EXT3_IOC_SETVERSION_OLD _IOW('v', 2, long)
194 #ifdef CONFIG_JBD_DEBUG
195 #define EXT3_IOC_WAIT_FOR_READONLY _IOR('f', 99, long)
197 -#define EXT3_IOC_GETRSVSZ _IOR('f', 5, long)
198 -#define EXT3_IOC_SETRSVSZ _IOW('f', 6, long)
200 +/* FIEMAP flags supported by ext3 */
201 +#define EXT3_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC)
205 @@ -996,6 +1000,9 @@ extern int ext3_writepage_trans_blocks(s
207 extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
209 +struct fiemap_extent_info;
210 +extern int ext3_fiemap(struct inode *, struct fiemap_extent_info *, __u64,
214 extern int ext3_orphan_add(handle_t *, struct inode *);
215 Index: linux-2.6.16.60-0.23/include/linux/ext3_extents.h
216 ===================================================================
217 --- linux-2.6.16.60-0.23.orig/include/linux/ext3_extents.h
218 +++ linux-2.6.16.60-0.23/include/linux/ext3_extents.h
219 @@ -170,7 +170,10 @@ struct ext3_extents_helpers {
221 typedef int (*ext_prepare_callback)(struct ext3_extents_tree *,
222 struct ext3_ext_path *,
223 - struct ext3_ext_cache *);
224 + struct ext3_ext_cache *,
225 + struct ext3_extent *);
227 +#define HAVE_EXT_PREPARE_CB_EXTENT
229 #define EXT_CONTINUE 0
231 @@ -179,6 +182,25 @@ typedef int (*ext_prepare_callback)(stru
233 #define EXT_MAX_BLOCK 0xffffffff
236 + * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an
237 + * initialized extent. This is 2^15 and not (2^16 - 1), since we use the
238 + * MSB of ee_len field in the extent datastructure to signify if this
239 + * particular extent is an initialized extent or an uninitialized (i.e.
241 + * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an
242 + * uninitialized extent.
243 + * If ee_len is <= 0x8000, it is an initialized extent. Otherwise, it is an
244 + * uninitialized one. In other words, if MSB of ee_len is set, it is an
245 + * uninitialized extent with only one special scenario when ee_len = 0x8000.
246 + * In this case we can not have an uninitialized extent of zero length and
247 + * thus we make it as a special case of initialized extent with 0x8000 length.
248 + * This way we get better extent-to-group alignment for initialized extents.
249 + * Hence, the maximum number of blocks we can have in an *initialized*
250 + * extent is 2^15 (32768) and in an *uninitialized* extent is 2^15-1 (32767).
252 +#define EXT_INIT_MAX_LEN (1UL << 15)
253 +#define EXT_UNINIT_MAX_LEN (EXT_INIT_MAX_LEN - 1)
255 #define EXT_FIRST_EXTENT(__hdr__) \
256 ((struct ext3_extent *) (((char *) (__hdr__)) + \
257 @@ -242,6 +264,12 @@ struct ext3_extent_tree_stats {
261 +static inline int ext3_ext_is_uninitialized(struct ext3_extent *ext)
263 + /* Extent with ee_len of 0x8000 is treated as an initialized extent */
264 + return (le16_to_cpu(ext->ee_len) > EXT_INIT_MAX_LEN);
267 extern int ext3_ext_search_left(struct ext3_extents_tree *, struct ext3_ext_path *, unsigned long *, unsigned long *);
268 extern int ext3_ext_search_right(struct ext3_extents_tree *, struct ext3_ext_path *, unsigned long *, unsigned long *);
269 extern void ext3_init_tree_desc(struct ext3_extents_tree *, struct inode *);
270 Index: linux-2.6.16.60-0.23/fs/ext3/extents.c
271 ===================================================================
272 --- linux-2.6.16.60-0.23.orig/fs/ext3/extents.c
273 +++ linux-2.6.16.60-0.23/fs/ext3/extents.c
275 #include <linux/string.h>
276 #include <linux/slab.h>
277 #include <linux/ext3_extents.h>
279 #include <asm/uaccess.h>
282 @@ -1488,7 +1489,7 @@ int ext3_ext_walk_space(struct ext3_exte
284 EXT_ASSERT(cbex.ec_len > 0);
285 EXT_ASSERT(path[depth].p_hdr);
286 - err = func(tree, path, &cbex);
287 + err = func(tree, path, &cbex, ex);
288 ext3_ext_drop_refs(path);
291 @@ -2502,7 +2503,109 @@ int ext3_ext_calc_blockmap_metadata(stru
292 ext3_init_tree_desc(&tree, inode);
293 return ext3_ext_calc_metadata_amount(&tree, blocks);
298 + * Callback function called for each extent to gather FIEMAP information.
300 +int ext3_ext_fiemap_cb(struct ext3_extents_tree *tree,
301 + struct ext3_ext_path *path, struct ext3_ext_cache *newex,
302 + struct ext3_extent *ex)
304 + struct fiemap_extent_info *fieinfo = (struct fiemap_extent_info *)tree->private;
305 + struct inode *inode = tree->inode;
306 + unsigned long blksize_bits = inode->i_sb->s_blocksize_bits;
313 + logical = (__u64)newex->ec_block << blksize_bits;
315 + if (newex->ec_type == EXT3_EXT_CACHE_GAP) {
318 + struct buffer_head *bh = NULL;
320 + offset = logical >> PAGE_SHIFT;
321 + page = find_get_page(inode->i_mapping, offset);
322 + if (!page || !page_has_buffers(page))
323 + return EXT_CONTINUE;
325 + bh = page_buffers(page);
328 + return EXT_CONTINUE;
330 + if (buffer_delay(bh)) {
331 + flags |= FIEMAP_EXTENT_DELALLOC;
332 + page_cache_release(page);
334 + page_cache_release(page);
335 + return EXT_CONTINUE;
339 + physical = (__u64)newex->ec_start << blksize_bits;
340 + length = (__u64)newex->ec_len << blksize_bits;
342 + if (ex && ext3_ext_is_uninitialized(ex))
343 + flags |= FIEMAP_EXTENT_UNWRITTEN;
346 + * If this extent reaches EXT_MAX_BLOCK, it must be last.
348 + * Or if ext3_ext_next_allocated_block is EXT_MAX_BLOCK,
349 + * this indicates no more allocated blocks.
351 + * XXX this might miss a single-block extent at EXT_MAX_BLOCK
353 + if (logical + length - 1 == EXT_MAX_BLOCK ||
354 + ext3_ext_next_allocated_block(path) == EXT_MAX_BLOCK)
355 + flags |= FIEMAP_EXTENT_LAST;
357 + error = fiemap_fill_next_extent(fieinfo, logical, physical,
358 + length, flags, inode->i_sb->s_dev);
364 + return EXT_CONTINUE;
367 +int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
368 + __u64 start, __u64 len)
370 + struct ext3_extents_tree tree;
371 + unsigned long start_blk;
372 + unsigned long len_blks;
375 + if (!(EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL))
376 + return -EOPNOTSUPP;
378 + if (fiemap_check_flags(fieinfo, EXT3_FIEMAP_FLAGS_COMPAT))
381 + start_blk = start >> inode->i_sb->s_blocksize_bits;
382 + len_blks = (len + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
384 + ext3_init_tree_desc(&tree, inode);
385 + tree.private = fieinfo;
388 + * Walk the extent tree gathering extent information.
389 + * ext3_ext_fiemap_cb will push extents back to user.
391 + down(&EXT3_I(inode)->truncate_sem);
392 + error = ext3_ext_walk_space(&tree, start_blk, len_blks,
393 + ext3_ext_fiemap_cb);
394 + up(&EXT3_I(inode)->truncate_sem);
399 EXPORT_SYMBOL(ext3_init_tree_desc);
400 EXPORT_SYMBOL(ext3_mark_inode_dirty);
401 EXPORT_SYMBOL(ext3_ext_invalidate_cache);
402 Index: linux-2.6.16.60-0.23/fs/ext3/fiemap.h
403 ===================================================================
405 +++ linux-2.6.16.60-0.23/fs/ext3/fiemap.h
408 + * FIEMAP ioctl infrastructure.
410 + * Copyright 2008 Sun Microsystems, Inc.
412 + * Author: Kalpak Shah <kalpak.shah@sun.com>
413 + * Andreas Dilger <adilger@sun.com>
416 +#ifndef _LINUX_EXT3_FIEMAP_H
417 +#define _LINUX_EXT3_FIEMAP_H
419 +struct fiemap_extent {
420 + __u64 fe_logical; /* logical offset in bytes for the start of
421 + * the extent from the beginning of the file */
422 + __u64 fe_physical; /* physical offset in bytes for the start
423 + * of the extent from the beginning of the disk */
424 + __u64 fe_length; /* length in bytes for this extent */
425 + __u32 fe_flags; /* FIEMAP_EXTENT_* flags for this extent */
426 + __u32 fe_device; /* device number for this extent */
430 + __u64 fm_start; /* logical offset (inclusive) at
431 + * which to start mapping (in) */
432 + __u64 fm_length; /* logical length of mapping which
433 + * userspace wants (in) */
434 + __u32 fm_flags; /* FIEMAP_FLAG_* flags for request (in/out) */
435 + __u32 fm_mapped_extents;/* number of extents that were mapped (out) */
436 + __u32 fm_extent_count; /* size of fm_extents array (in) */
438 + struct fiemap_extent fm_extents[0]; /* array of mapped extents (out) */
442 + * FIEMAP helper definition.
444 +struct fiemap_extent_info {
445 + unsigned int fi_flags; /* Flags as passed from user */
446 + unsigned int fi_extents_mapped; /* Number of mapped extents */
447 + unsigned int fi_extents_max; /* Size of fiemap_extent array*/
448 + struct fiemap_extent *fi_extents_start; /* Start of fiemap_extent array */
451 +int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
452 +int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical,
453 + u64 phys, u64 len, u32 flags, u32 lun);
455 +#define FIEMAP_MAX_OFFSET (~0ULL)
457 +#define FIEMAP_FLAG_SYNC 0x00000001 /* sync file data before map */
458 +#define FIEMAP_FLAG_XATTR 0x00000002 /* map extended attribute tree */
460 +/* ldiskfs only supports FLAG_SYNC flag currently */
461 +#define FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
464 +#define FIEMAP_EXTENT_LAST 0x00000001 /* Last extent in file. */
465 +#define FIEMAP_EXTENT_UNKNOWN 0x00000002 /* Data location unknown. */
466 +#define FIEMAP_EXTENT_DELALLOC 0x00000004 /* Location still pending.
467 + * Sets EXTENT_UNKNOWN. */
468 +#define FIEMAP_EXTENT_NO_DIRECT 0x00000008 /* Data mapping undefined */
469 +#define FIEMAP_EXTENT_SECONDARY 0x00000010 /* Data copied offline. May
470 + * set EXTENT_NO_DIRECT. */
471 +#define FIEMAP_EXTENT_NET 0x00000020 /* Data stored remotely.
472 + * Sets EXTENT_NO_DIRECT. */
473 +#define FIEMAP_EXTENT_DATA_COMPRESSED 0x00000040 /* Data is compressed by fs.
474 + * Sets EXTENT_NO_DIRECT. */
475 +#define FIEMAP_EXTENT_DATA_ENCRYPTED 0x00000080 /* Data is encrypted by fs.
476 + * Sets EXTENT_NO_DIRECT. */
477 +#define FIEMAP_EXTENT_NOT_ALIGNED 0x00000100 /* Extent offsets may not be
478 + * block aligned. */
479 +#define FIEMAP_EXTENT_DATA_INLINE 0x00000200 /* Data mixed with metadata.
480 + * Sets EXTENT_NOT_ALIGNED.*/
481 +#define FIEMAP_EXTENT_DATA_TAIL 0x00000400 /* Multiple files in block.
482 + * Sets EXTENT_NOT_ALIGNED.*/
483 +#define FIEMAP_EXTENT_UNWRITTEN 0x00000800 /* Space allocated, but
484 + * no data (i.e. zero). */
485 +#define FIEMAP_EXTENT_MERGED 0x00001000 /* File does not natively
486 + * support extents. Result
487 + * merged for efficiency. */
489 +#endif /* _LINUX_EXT3_FIEMAP_H */