Merge branch 'fixes-2.6.39' into for-2.6.40

1 files changed, 165 insertions, 48 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7516fb9c0bd..dd2cb5076ff 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -44,6 +44,8 @@
 #include "ext4_jbd2.h"
 #include "ext4_extents.h"
 
+#include <trace/events/ext4.h>
+
 static int ext4_ext_truncate_extend_restart(handle_t *handle,
                                             struct inode *inode,
                                             int needed)
@@ -664,6 +666,8 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
                 if (unlikely(!bh))
                         goto err;
                 if (!bh_uptodate_or_lock(bh)) {
+                        trace_ext4_ext_load_extent(inode, block,
+                                                path[ppos].p_block);
                         if (bh_submit_read(bh) < 0) {
                                 put_bh(bh);
                                 goto err;
@@ -1034,7 +1038,7 @@ cleanup:
                 for (i = 0; i < depth; i++) {
                         if (!ablocks[i])
                                 continue;
-                        ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
+                        ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
                                          EXT4_FREE_BLOCKS_METADATA);
                 }
         }
@@ -2059,7 +2063,7 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
         if (err)
                 return err;
         ext_debug("index is empty, remove it, free block %llu\n", leaf);
-        ext4_free_blocks(handle, inode, 0, leaf, 1,
+        ext4_free_blocks(handle, inode, NULL, leaf, 1,
                          EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
         return err;
 }
@@ -2156,7 +2160,7 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
                 num = le32_to_cpu(ex->ee_block) + ee_len - from;
                 start = ext4_ext_pblock(ex) + ee_len - num;
                 ext_debug("free last %u blocks starting %llu\n", num, start);
-                ext4_free_blocks(handle, inode, 0, start, num, flags);
+                ext4_free_blocks(handle, inode, NULL, start, num, flags);
         } else if (from == le32_to_cpu(ex->ee_block)
                    && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
                 printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
@@ -3108,14 +3112,13 @@ static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
 {
         int i, depth;
         struct ext4_extent_header *eh;
-        struct ext4_extent *ex, *last_ex;
+        struct ext4_extent *last_ex;
 
         if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
                 return 0;
 
         depth = ext_depth(inode);
         eh = path[depth].p_hdr;
-        ex = path[depth].p_ext;
 
         if (unlikely(!eh->eh_entries)) {
                 EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and "
@@ -3295,9 +3298,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
                         struct ext4_map_blocks *map, int flags)
 {
         struct ext4_ext_path *path = NULL;
-        struct ext4_extent_header *eh;
         struct ext4_extent newex, *ex;
-        ext4_fsblk_t newblock;
+        ext4_fsblk_t newblock = 0;
         int err = 0, depth, ret;
         unsigned int allocated = 0;
         struct ext4_allocation_request ar;
@@ -3305,6 +3307,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 
         ext_debug("blocks %u/%u requested for inode %lu\n",
                   map->m_lblk, map->m_len, inode->i_ino);
+        trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
 
         /* check in cache */
         if (ext4_ext_in_cache(inode, map->m_lblk, &newex)) {
@@ -3352,7 +3355,6 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
                 err = -EIO;
                 goto out2;
         }
-        eh = path[depth].p_hdr;
 
         ex = path[depth].p_ext;
         if (ex) {
@@ -3485,7 +3487,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
                 /* not a good idea to call discard here directly,
                  * but otherwise we'd need to call it every free() */
                 ext4_discard_preallocations(inode);
-                ext4_free_blocks(handle, inode, 0, ext4_ext_pblock(&newex),
+                ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
                                  ext4_ext_get_actual_len(&newex), 0);
                 goto out2;
         }
@@ -3525,6 +3527,8 @@ out2:
                 ext4_ext_drop_refs(path);
                 kfree(path);
         }
+        trace_ext4_ext_map_blocks_exit(inode, map->m_lblk,
+                newblock, map->m_len, err ? err : allocated);
         return err ? err : allocated;
 }
 
@@ -3658,6 +3662,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
         if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
                 return -EOPNOTSUPP;
 
+        trace_ext4_fallocate_enter(inode, offset, len, mode);
         map.m_lblk = offset >> blkbits;
         /*
          * We can't just convert len to max_blocks because
@@ -3673,6 +3678,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
         ret = inode_newsize_ok(inode, (len + offset));
         if (ret) {
                 mutex_unlock(&inode->i_mutex);
+                trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
                 return ret;
         }
 retry:
@@ -3717,6 +3723,8 @@ retry:
                 goto retry;
         }
         mutex_unlock(&inode->i_mutex);
+        trace_ext4_fallocate_exit(inode, offset, max_blocks,
+                                ret > 0 ? ret2 : ret);
         return ret > 0 ? ret2 : ret;
 }
 
@@ -3775,6 +3783,7 @@ int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
         }
         return ret > 0 ? ret2 : ret;
 }
+
 /*
  * Callback function called for each extent to gather FIEMAP information.
  */
@@ -3782,38 +3791,162 @@ static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
                        struct ext4_ext_cache *newex, struct ext4_extent *ex,
                        void *data)
 {
-        struct fiemap_extent_info *fieinfo = data;
-        unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
         __u64   logical;
         __u64   physical;
         __u64   length;
+        loff_t  size;
         __u32   flags = 0;
-        int     error;
+        int             ret = 0;
+        struct fiemap_extent_info *fieinfo = data;
+        unsigned char blksize_bits;
 
-        logical =  (__u64)newex->ec_block << blksize_bits;
+        blksize_bits = inode->i_sb->s_blocksize_bits;
+        logical = (__u64)newex->ec_block << blksize_bits;
 
         if (newex->ec_start == 0) {
-                pgoff_t offset;
-                struct page *page;
+                /*
+                 * No extent in extent-tree contains block @newex->ec_start,
+                 * then the block may stay in 1)a hole or 2)delayed-extent.
+                 *
+                 * Holes or delayed-extents are processed as follows.
+                 * 1. lookup dirty pages with specified range in pagecache.
+                 *    If no page is got, then there is no delayed-extent and
+                 *    return with EXT_CONTINUE.
+                 * 2. find the 1st mapped buffer,
+                 * 3. check if the mapped buffer is both in the request range
+                 *    and a delayed buffer. If not, there is no delayed-extent,
+                 *    then return.
+                 * 4. a delayed-extent is found, the extent will be collected.
+                 */
+                ext4_lblk_t     end = 0;
+                pgoff_t         last_offset;
+                pgoff_t         offset;
+                pgoff_t         index;
+                struct page     **pages = NULL;
                 struct buffer_head *bh = NULL;
+                struct buffer_head *head = NULL;
+                unsigned int nr_pages = PAGE_SIZE / sizeof(struct page *);
+
+                pages = kmalloc(PAGE_SIZE, GFP_KERNEL);
+                if (pages == NULL)
+                        return -ENOMEM;
 
                 offset = logical >> PAGE_SHIFT;
-                page = find_get_page(inode->i_mapping, offset);
-                if (!page || !page_has_buffers(page))
-                        return EXT_CONTINUE;
+repeat:
+                last_offset = offset;
+                head = NULL;
+                ret = find_get_pages_tag(inode->i_mapping, &offset,
+                                        PAGECACHE_TAG_DIRTY, nr_pages, pages);
+
+                if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
+                        /* First time, try to find a mapped buffer. */
+                        if (ret == 0) {
+out:
+                                for (index = 0; index < ret; index++)
+                                        page_cache_release(pages[index]);
+                                /* just a hole. */
+                                kfree(pages);
+                                return EXT_CONTINUE;
+                        }
 
-                bh = page_buffers(page);
+                        /* Try to find the 1st mapped buffer. */
+                        end = ((__u64)pages[0]->index << PAGE_SHIFT) >>
+                                  blksize_bits;
+                        if (!page_has_buffers(pages[0]))
+                                goto out;
+                        head = page_buffers(pages[0]);
+                        if (!head)
+                                goto out;
 
-                if (!bh)
-                        return EXT_CONTINUE;
+                        bh = head;
+                        do {
+                                if (buffer_mapped(bh)) {
+                                        /* get the 1st mapped buffer. */
+                                        if (end > newex->ec_block +
+                                                newex->ec_len)
+                                                /* The buffer is out of
+                                                 * the request range.
+                                                 */
+                                                goto out;
+                                        goto found_mapped_buffer;
+                                }
+                                bh = bh->b_this_page;
+                                end++;
+                        } while (bh != head);
 
-                if (buffer_delay(bh)) {
-                        flags |= FIEMAP_EXTENT_DELALLOC;
-                        page_cache_release(page);
+                        /* No mapped buffer found. */
+                        goto out;
                 } else {
-                        page_cache_release(page);
-                        return EXT_CONTINUE;
+                        /*Find contiguous delayed buffers. */
+                        if (ret > 0 && pages[0]->index == last_offset)
+                                head = page_buffers(pages[0]);
+                        bh = head;
                 }
+
+found_mapped_buffer:
+                if (bh != NULL && buffer_delay(bh)) {
+                        /* 1st or contiguous delayed buffer found. */
+                        if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
+                                /*
+                                 * 1st delayed buffer found, record
+                                 * the start of extent.
+                                 */
+                                flags |= FIEMAP_EXTENT_DELALLOC;
+                                newex->ec_block = end;
+                                logical = (__u64)end << blksize_bits;
+                        }
+                        /* Find contiguous delayed buffers. */
+                        do {
+                                if (!buffer_delay(bh))
+                                        goto found_delayed_extent;
+                                bh = bh->b_this_page;
+                                end++;
+                        } while (bh != head);
+
+                        for (index = 1; index < ret; index++) {
+                                if (!page_has_buffers(pages[index])) {
+                                        bh = NULL;
+                                        break;
+                                }
+                                head = page_buffers(pages[index]);
+                                if (!head) {
+                                        bh = NULL;
+                                        break;
+                                }
+                                if (pages[index]->index !=
+                                        pages[0]->index + index) {
+                                        /* Blocks are not contiguous. */
+                                        bh = NULL;
+                                        break;
+                                }
+                                bh = head;
+                                do {
+                                        if (!buffer_delay(bh))
+                                                /* Delayed-extent ends. */
+                                                goto found_delayed_extent;
+                                        bh = bh->b_this_page;
+                                        end++;
+                                } while (bh != head);
+                        }
+                } else if (!(flags & FIEMAP_EXTENT_DELALLOC))
+                        /* a hole found. */
+                        goto out;
+
+found_delayed_extent:
+                newex->ec_len = min(end - newex->ec_block,
+                                                (ext4_lblk_t)EXT_INIT_MAX_LEN);
+                if (ret == nr_pages && bh != NULL &&
+                        newex->ec_len < EXT_INIT_MAX_LEN &&
+                        buffer_delay(bh)) {
+                        /* Have not collected an extent and continue. */
+                        for (index = 0; index < ret; index++)
+                                page_cache_release(pages[index]);
+                        goto repeat;
+                }
+
+                for (index = 0; index < ret; index++)
+                        page_cache_release(pages[index]);
+                kfree(pages);
         }
 
         physical = (__u64)newex->ec_start << blksize_bits;
@@ -3822,32 +3955,16 @@ static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
         if (ex && ext4_ext_is_uninitialized(ex))
                 flags |= FIEMAP_EXTENT_UNWRITTEN;
 
-        /*
-         * If this extent reaches EXT_MAX_BLOCK, it must be last.
-         *
-         * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
-         * this also indicates no more allocated blocks.
-         *
-         * XXX this might miss a single-block extent at EXT_MAX_BLOCK
-         */
-        if (ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK ||
-            newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK) {
-                loff_t size = i_size_read(inode);
-                loff_t bs = EXT4_BLOCK_SIZE(inode->i_sb);
-
+        size = i_size_read(inode);
+        if (logical + length >= size)
                 flags |= FIEMAP_EXTENT_LAST;
-                if ((flags & FIEMAP_EXTENT_DELALLOC) &&
-                    logical+length > size)
-                        length = (size - logical + bs - 1) & ~(bs-1);
-        }
 
-        error = fiemap_fill_next_extent(fieinfo, logical, physical,
+        ret = fiemap_fill_next_extent(fieinfo, logical, physical,
                                         length, flags);
-        if (error < 0)
-                return error;
-        if (error == 1)
+        if (ret < 0)
+                return ret;
+        if (ret == 1)
                 return EXT_BREAK;
-
         return EXT_CONTINUE;
 }