diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 55504338491d8e5a4989ff98e5bd5572ecf61946..9ebe2dd31f2a7f650e8b36c3ba6da6a69e68dc2a 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2765,14 +2765,11 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
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;
@@ -2793,6 +2790,20 @@ static struct page *extent_same_get_page(struct inode *inode, u64 off)
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
@@ -2818,52 +2829,120 @@ static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
}
}
-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);
@@ -2875,15 +2954,12 @@ static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
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;
@@ -2914,6 +2990,7 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
{
int ret;
u64 len = olen;
+ struct cmp_pages cmp;
/*
* btrfs_clone() can't handle extents in the same file
@@ -2926,7 +3003,7 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
if (len == 0)
return 0;
- btrfs_double_lock(src, loff, dst, dst_loff, len);
+ btrfs_double_inode_lock(src, dst);
ret = extent_same_check_offsets(src, loff, &len, olen);
if (ret)
@@ -2943,13 +3020,22 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
goto out_unlock;
}
+ ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
+ if (ret)
+ goto out_unlock;
+
+ 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);
+ ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
if (ret == 0)
ret = btrfs_clone(src, dst, loff, olen, len, dst_loff);
+ 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);
+ btrfs_double_inode_unlock(src, dst);
return ret;
}