static int btrfs_clone(struct inode *src, struct inode *inode,
- u64 off, u64 olen, u64 olen_aligned, u64 destoff);
+ u64 off, u64 olen, u64 olen_aligned, u64 destoff,
+ int no_time_update);
/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
return ret;
}
-static struct page *extent_same_get_page(struct inode *inode, u64 off)
+static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
{
struct page *page;
- pgoff_t index;
struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
- index = off >> PAGE_CACHE_SHIFT;
-
page = grab_cache_page(inode->i_mapping, index);
if (!page)
return NULL;
return page;
}
+static int gather_extent_pages(struct inode *inode, struct page **pages,
+ int num_pages, u64 off)
+{
+ int i;
+ pgoff_t index = off >> PAGE_CACHE_SHIFT;
+
+ for (i = 0; i < num_pages; i++) {
+ pages[i] = extent_same_get_page(inode, index + i);
+ if (!pages[i])
+ return -ENOMEM;
+ }
+ return 0;
+}
+
static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
{
/* do any pending delalloc/csum calc on src, one way or
}
}
-static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
- struct inode *inode2, u64 loff2, u64 len)
+static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
{
- unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
- unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
-
mutex_unlock(&inode1->i_mutex);
mutex_unlock(&inode2->i_mutex);
}
-static void btrfs_double_lock(struct inode *inode1, u64 loff1,
- struct inode *inode2, u64 loff2, u64 len)
+static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
+{
+ if (inode1 < inode2)
+ swap(inode1, inode2);
+
+ mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
+ if (inode1 != inode2)
+ mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
+}
+
+static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
+ struct inode *inode2, u64 loff2, u64 len)
+{
+ unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
+ unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
+}
+
+static void btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
+ struct inode *inode2, u64 loff2, u64 len)
{
if (inode1 < inode2) {
swap(inode1, inode2);
swap(loff1, loff2);
}
-
- mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
lock_extent_range(inode1, loff1, len);
- if (inode1 != inode2) {
- mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
+ if (inode1 != inode2)
lock_extent_range(inode2, loff2, len);
+}
+
+struct cmp_pages {
+ int num_pages;
+ struct page **src_pages;
+ struct page **dst_pages;
+};
+
+static void btrfs_cmp_data_free(struct cmp_pages *cmp)
+{
+ int i;
+ struct page *pg;
+
+ for (i = 0; i < cmp->num_pages; i++) {
+ pg = cmp->src_pages[i];
+ if (pg)
+ page_cache_release(pg);
+ pg = cmp->dst_pages[i];
+ if (pg)
+ page_cache_release(pg);
+ }
+ kfree(cmp->src_pages);
+ kfree(cmp->dst_pages);
+}
+
+static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
+ struct inode *dst, u64 dst_loff,
+ u64 len, struct cmp_pages *cmp)
+{
+ int ret;
+ int num_pages = PAGE_CACHE_ALIGN(len) >> PAGE_CACHE_SHIFT;
+ struct page **src_pgarr, **dst_pgarr;
+
+ /*
+ * We must gather up all the pages before we initiate our
+ * extent locking. We use an array for the page pointers. Size
+ * of the array is bounded by len, which is in turn bounded by
+ * BTRFS_MAX_DEDUPE_LEN.
+ */
+ src_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
+ dst_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
+ if (!src_pgarr || !dst_pgarr) {
+ kfree(src_pgarr);
+ kfree(dst_pgarr);
+ return -ENOMEM;
}
+ cmp->num_pages = num_pages;
+ cmp->src_pages = src_pgarr;
+ cmp->dst_pages = dst_pgarr;
+
+ ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
+ if (ret)
+ goto out;
+
+ ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);
+
+out:
+ if (ret)
+ btrfs_cmp_data_free(cmp);
+ return 0;
}
static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
- u64 dst_loff, u64 len)
+ u64 dst_loff, u64 len, struct cmp_pages *cmp)
{
int ret = 0;
+ int i;
struct page *src_page, *dst_page;
unsigned int cmp_len = PAGE_CACHE_SIZE;
void *addr, *dst_addr;
+ i = 0;
while (len) {
if (len < PAGE_CACHE_SIZE)
cmp_len = len;
- src_page = extent_same_get_page(src, loff);
- if (!src_page)
- return -EINVAL;
- dst_page = extent_same_get_page(dst, dst_loff);
- if (!dst_page) {
- page_cache_release(src_page);
- return -EINVAL;
- }
+ BUG_ON(i >= cmp->num_pages);
+
+ src_page = cmp->src_pages[i];
+ dst_page = cmp->dst_pages[i];
+
addr = kmap_atomic(src_page);
dst_addr = kmap_atomic(dst_page);
kunmap_atomic(addr);
kunmap_atomic(dst_addr);
- page_cache_release(src_page);
- page_cache_release(dst_page);
if (ret)
break;
- loff += cmp_len;
- dst_loff += cmp_len;
len -= cmp_len;
+ i++;
}
return ret;
{
int ret;
u64 len = olen;
+ struct cmp_pages cmp;
+ int same_inode = 0;
+ u64 same_lock_start = 0;
+ u64 same_lock_len = 0;
- /*
- * btrfs_clone() can't handle extents in the same file
- * yet. Once that works, we can drop this check and replace it
- * with a check for the same inode, but overlapping extents.
- */
if (src == dst)
- return -EINVAL;
+ same_inode = 1;
if (len == 0)
return 0;
- btrfs_double_lock(src, loff, dst, dst_loff, len);
+ if (same_inode) {
+ mutex_lock(&src->i_mutex);
- ret = extent_same_check_offsets(src, loff, &len, olen);
- if (ret)
- goto out_unlock;
+ ret = extent_same_check_offsets(src, loff, &len, olen);
+ if (ret)
+ goto out_unlock;
- ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
- if (ret)
- goto out_unlock;
+ /*
+ * Single inode case wants the same checks, except we
+ * don't want our length pushed out past i_size as
+ * comparing that data range makes no sense.
+ *
+ * extent_same_check_offsets() will do this for an
+ * unaligned length at i_size, so catch it here and
+ * reject the request.
+ *
+ * This effectively means we require aligned extents
+ * for the single-inode case, whereas the other cases
+ * allow an unaligned length so long as it ends at
+ * i_size.
+ */
+ if (len != olen) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ /* Check for overlapping ranges */
+ if (dst_loff + len > loff && dst_loff < loff + len) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ same_lock_start = min_t(u64, loff, dst_loff);
+ same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
+ } else {
+ btrfs_double_inode_lock(src, dst);
+
+ ret = extent_same_check_offsets(src, loff, &len, olen);
+ if (ret)
+ goto out_unlock;
+
+ ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
+ if (ret)
+ goto out_unlock;
+ }
/* don't make the dst file partly checksummed */
if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
goto out_unlock;
}
- ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
+ ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
+ if (ret)
+ goto out_unlock;
+
+ if (same_inode)
+ lock_extent_range(src, same_lock_start, same_lock_len);
+ else
+ btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
+
+ /* pass original length for comparison so we stay within i_size */
+ ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
if (ret == 0)
- ret = btrfs_clone(src, dst, loff, olen, len, dst_loff);
+ ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
+
+ if (same_inode)
+ unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
+ same_lock_start + same_lock_len - 1);
+ else
+ btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
+ btrfs_cmp_data_free(&cmp);
out_unlock:
- btrfs_double_unlock(src, loff, dst, dst_loff, len);
+ if (same_inode)
+ mutex_unlock(&src->i_mutex);
+ else
+ btrfs_double_inode_unlock(src, dst);
return ret;
}
struct inode *inode,
u64 endoff,
const u64 destoff,
- const u64 olen)
+ const u64 olen,
+ int no_time_update)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret;
inode_inc_iversion(inode);
- inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ if (!no_time_update)
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
/*
* We round up to the block size at eof when determining which
* extents to clone above, but shouldn't round up the file size.
* @inode: Inode to clone to
* @off: Offset within source to start clone from
* @olen: Original length, passed by user, of range to clone
- * @olen_aligned: Block-aligned value of olen, extent_same uses
- * identical values here
+ * @olen_aligned: Block-aligned value of olen
* @destoff: Offset within @inode to start clone
+ * @no_time_update: Whether to update mtime/ctime on the target inode
*/
static int btrfs_clone(struct inode *src, struct inode *inode,
const u64 off, const u64 olen, const u64 olen_aligned,
- const u64 destoff)
+ const u64 destoff, int no_time_update)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_path *path = NULL;
root->sectorsize);
ret = clone_finish_inode_update(trans, inode,
last_dest_end,
- destoff, olen);
+ destoff, olen,
+ no_time_update);
if (ret)
goto out;
if (new_key.offset + datal >= destoff + len)
clone_update_extent_map(inode, trans, NULL, last_dest_end,
destoff + len - last_dest_end);
ret = clone_finish_inode_update(trans, inode, destoff + len,
- destoff, olen);
+ destoff, olen, no_time_update);
}
out:
lock_extent_range(inode, destoff, len);
}
- ret = btrfs_clone(src, inode, off, olen, len, destoff);
+ ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
if (same_inode) {
u64 lock_start = min_t(u64, off, destoff);
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