f2fs: report unwritten area in f2fs_fiemap

This patch slightly changes f2fs_fiemap function to report unwritten area.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 3b762611ff6d4cce993cc444451a5bb78b7f4534..842fcdd9d22672b5eac3bff3eb1c097a66ad889b 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1241,6 +1241,8 @@ static int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
        if (dn.data_blkaddr != NULL_ADDR) {
                map->m_flags = F2FS_MAP_MAPPED;
                map->m_pblk = dn.data_blkaddr;
+               if (dn.data_blkaddr == NEW_ADDR)
+                       map->m_flags |= F2FS_MAP_UNWRITTEN;
        } else if (create) {
                err = __allocate_data_block(&dn);
                if (err)
@@ -1288,7 +1290,10 @@ get_next:
                        blkaddr = dn.data_blkaddr;
                }
                /* Give more consecutive addresses for the readahead */
-               if (map->m_pblk != NEW_ADDR && blkaddr == (map->m_pblk + ofs)) {
+               if ((map->m_pblk != NEW_ADDR &&
+                               blkaddr == (map->m_pblk + ofs)) ||
+                               (map->m_pblk == NEW_ADDR &&
+                               blkaddr == NEW_ADDR)) {
                        ofs++;
                        dn.ofs_in_node++;
                        pgofs++;
@@ -1339,11 +1344,117 @@ static int get_data_block_fiemap(struct inode *inode, sector_t iblock,
        return __get_data_block(inode, iblock, bh_result, create, true);
 }
 
+static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
+{
+       return (offset >> inode->i_blkbits);
+}
+
+static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
+{
+       return (blk << inode->i_blkbits);
+}
+
 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                u64 start, u64 len)
 {
-       return generic_block_fiemap(inode, fieinfo,
-                               start, len, get_data_block_fiemap);
+       struct buffer_head map_bh;
+       sector_t start_blk, last_blk;
+       loff_t isize = i_size_read(inode);
+       u64 logical = 0, phys = 0, size = 0;
+       u32 flags = 0;
+       bool past_eof = false, whole_file = false;
+       int ret = 0;
+
+       ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
+       if (ret)
+               return ret;
+
+       mutex_lock(&inode->i_mutex);
+
+       if (len >= isize) {
+               whole_file = true;
+               len = isize;
+       }
+
+       if (logical_to_blk(inode, len) == 0)
+               len = blk_to_logical(inode, 1);
+
+       start_blk = logical_to_blk(inode, start);
+       last_blk = logical_to_blk(inode, start + len - 1);
+next:
+       memset(&map_bh, 0, sizeof(struct buffer_head));
+       map_bh.b_size = len;
+
+       ret = get_data_block_fiemap(inode, start_blk, &map_bh, 0);
+       if (ret)
+               goto out;
+
+       /* HOLE */
+       if (!buffer_mapped(&map_bh)) {
+               start_blk++;
+
+               if (!past_eof && blk_to_logical(inode, start_blk) >= isize)
+                       past_eof = 1;
+
+               if (past_eof && size) {
+                       flags |= FIEMAP_EXTENT_LAST;
+                       ret = fiemap_fill_next_extent(fieinfo, logical,
+                                       phys, size, flags);
+               } else if (size) {
+                       ret = fiemap_fill_next_extent(fieinfo, logical,
+                                       phys, size, flags);
+                       size = 0;
+               }
+
+               /* if we have holes up to/past EOF then we're done */
+               if (start_blk > last_blk || past_eof || ret)
+                       goto out;
+       } else {
+               if (start_blk > last_blk && !whole_file) {
+                       ret = fiemap_fill_next_extent(fieinfo, logical,
+                                       phys, size, flags);
+                       goto out;
+               }
+
+               /*
+                * if size != 0 then we know we already have an extent
+                * to add, so add it.
+                */
+               if (size) {
+                       ret = fiemap_fill_next_extent(fieinfo, logical,
+                                       phys, size, flags);
+                       if (ret)
+                               goto out;
+               }
+
+               logical = blk_to_logical(inode, start_blk);
+               phys = blk_to_logical(inode, map_bh.b_blocknr);
+               size = map_bh.b_size;
+               flags = 0;
+               if (buffer_unwritten(&map_bh))
+                       flags = FIEMAP_EXTENT_UNWRITTEN;
+
+               start_blk += logical_to_blk(inode, size);
+
+               /*
+                * If we are past the EOF, then we need to make sure as
+                * soon as we find a hole that the last extent we found
+                * is marked with FIEMAP_EXTENT_LAST
+                */
+               if (!past_eof && logical + size >= isize)
+                       past_eof = true;
+       }
+       cond_resched();
+       if (fatal_signal_pending(current))
+               ret = -EINTR;
+       else
+               goto next;
+out:
+       if (ret == 1)
+               ret = 0;
+
+       mutex_unlock(&inode->i_mutex);
+       return ret;
 }
 
 /*

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 160945f1707a83fdbda052f55a6a26bcf4f87863..477e65fe7665cbcaccee6726bf56aec9d04c33a1 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -330,7 +330,9 @@ struct extent_tree {
  */
 #define F2FS_MAP_NEW           (1 << BH_New)
 #define F2FS_MAP_MAPPED                (1 << BH_Mapped)
-#define F2FS_MAP_FLAGS         (F2FS_MAP_NEW | F2FS_MAP_MAPPED)
+#define F2FS_MAP_UNWRITTEN     (1 << BH_Unwritten)
+#define F2FS_MAP_FLAGS         (F2FS_MAP_NEW | F2FS_MAP_MAPPED |\
+                               F2FS_MAP_UNWRITTEN)
 
 struct f2fs_map_blocks {
        block_t m_pblk;