ext4: Introduce ext4_lblk_t

This patch adds a new data type ext4_lblk_t to represent
the logical file blocks.

This is the preparatory patch to support large files in ext4
The follow up patch with convert the ext4_inode i_blocks to
represent the number of blocks in file system block size. This
changes makes it possible to have a block number 2**32 -1 which
will result in overflow if the block number is represented by
signed long. This patch convert all the block number to type
ext4_lblk_t which is typedef to __u32

Also remove dead code ext4_ext_walk_space

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>

1 files changed, 64 insertions, 154 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 85287742f2ae..19d8059b58aa 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -144,7 +144,7 @@ static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
 
 static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
                               struct ext4_ext_path *path,
-                              ext4_fsblk_t block)
+                              ext4_lblk_t block)
 {
         struct ext4_inode_info *ei = EXT4_I(inode);
         ext4_fsblk_t bg_start;
@@ -367,13 +367,14 @@ static void ext4_ext_drop_refs(struct ext4_ext_path *path)
  * the header must be checked before calling this
  */
 static void
-ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block)
+ext4_ext_binsearch_idx(struct inode *inode,
+                        struct ext4_ext_path *path, ext4_lblk_t block)
 {
         struct ext4_extent_header *eh = path->p_hdr;
         struct ext4_extent_idx *r, *l, *m;
 
 
-        ext_debug("binsearch for %d(idx):  ", block);
+        ext_debug("binsearch for %lu(idx):  ", (unsigned long)block);
 
         l = EXT_FIRST_INDEX(eh) + 1;
         r = EXT_LAST_INDEX(eh);
@@ -425,7 +426,8 @@ ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int bloc
  * the header must be checked before calling this
  */
 static void
-ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
+ext4_ext_binsearch(struct inode *inode,
+                struct ext4_ext_path *path, ext4_lblk_t block)
 {
         struct ext4_extent_header *eh = path->p_hdr;
         struct ext4_extent *r, *l, *m;
@@ -438,7 +440,7 @@ ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
                 return;
         }
 
-        ext_debug("binsearch for %d:  ", block);
+        ext_debug("binsearch for %lu:  ", (unsigned long)block);
 
         l = EXT_FIRST_EXTENT(eh) + 1;
         r = EXT_LAST_EXTENT(eh);
@@ -494,7 +496,8 @@ int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
 }
 
 struct ext4_ext_path *
-ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
+ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
+                                        struct ext4_ext_path *path)
 {
         struct ext4_extent_header *eh;
         struct buffer_head *bh;
@@ -979,8 +982,8 @@ repeat:
                 /* refill path */
                 ext4_ext_drop_refs(path);
                 path = ext4_ext_find_extent(inode,
-                                            le32_to_cpu(newext->ee_block),
-                                            path);
+                                    (ext4_lblk_t)le32_to_cpu(newext->ee_block),
+                                    path);
                 if (IS_ERR(path))
                         err = PTR_ERR(path);
         } else {
@@ -992,8 +995,8 @@ repeat:
                 /* refill path */
                 ext4_ext_drop_refs(path);
                 path = ext4_ext_find_extent(inode,
-                                            le32_to_cpu(newext->ee_block),
-                                            path);
+                                   (ext4_lblk_t)le32_to_cpu(newext->ee_block),
+                                    path);
                 if (IS_ERR(path)) {
                         err = PTR_ERR(path);
                         goto out;
@@ -1021,7 +1024,7 @@ out:
  * allocated block. Thus, index entries have to be consistent
  * with leaves.
  */
-static unsigned long
+static ext4_lblk_t
 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
 {
         int depth;
@@ -1054,7 +1057,7 @@ ext4_ext_next_allocated_block(struct ext4_ext_path *path)
  * ext4_ext_next_leaf_block:
  * returns first allocated block from next leaf or EXT_MAX_BLOCK
  */
-static unsigned ext4_ext_next_leaf_block(struct inode *inode,
+static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode,
                                         struct ext4_ext_path *path)
 {
         int depth;
@@ -1072,7 +1075,8 @@ static unsigned ext4_ext_next_leaf_block(struct inode *inode,
         while (depth >= 0) {
                 if (path[depth].p_idx !=
                                 EXT_LAST_INDEX(path[depth].p_hdr))
-                  return le32_to_cpu(path[depth].p_idx[1].ei_block);
+                        return (ext4_lblk_t)
+                                le32_to_cpu(path[depth].p_idx[1].ei_block);
                 depth--;
         }
 
@@ -1239,7 +1243,7 @@ unsigned int ext4_ext_check_overlap(struct inode *inode,
                                     struct ext4_extent *newext,
                                     struct ext4_ext_path *path)
 {
-        unsigned long b1, b2;
+        ext4_lblk_t b1, b2;
         unsigned int depth, len1;
         unsigned int ret = 0;
 
@@ -1260,7 +1264,7 @@ unsigned int ext4_ext_check_overlap(struct inode *inode,
                         goto out;
         }
 
-        /* check for wrap through zero */
+        /* check for wrap through zero on extent logical start block*/
         if (b1 + len1 < b1) {
                 len1 = EXT_MAX_BLOCK - b1;
                 newext->ee_len = cpu_to_le16(len1);
@@ -1290,7 +1294,8 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
         struct ext4_extent *ex, *fex;
         struct ext4_extent *nearex; /* nearest extent */
         struct ext4_ext_path *npath = NULL;
-        int depth, len, err, next;
+        int depth, len, err;
+        ext4_lblk_t next;
         unsigned uninitialized = 0;
 
         BUG_ON(ext4_ext_get_actual_len(newext) == 0);
@@ -1435,114 +1440,8 @@ cleanup:
         return err;
 }
 
-int ext4_ext_walk_space(struct inode *inode, unsigned long block,
-                        unsigned long num, ext_prepare_callback func,
-                        void *cbdata)
-{
-        struct ext4_ext_path *path = NULL;
-        struct ext4_ext_cache cbex;
-        struct ext4_extent *ex;
-        unsigned long next, start = 0, end = 0;
-        unsigned long last = block + num;
-        int depth, exists, err = 0;
-
-        BUG_ON(func == NULL);
-        BUG_ON(inode == NULL);
-
-        while (block < last && block != EXT_MAX_BLOCK) {
-                num = last - block;
-                /* find extent for this block */
-                path = ext4_ext_find_extent(inode, block, path);
-                if (IS_ERR(path)) {
-                        err = PTR_ERR(path);
-                        path = NULL;
-                        break;
-                }
-
-                depth = ext_depth(inode);
-                BUG_ON(path[depth].p_hdr == NULL);
-                ex = path[depth].p_ext;
-                next = ext4_ext_next_allocated_block(path);
-
-                exists = 0;
-                if (!ex) {
-                        /* there is no extent yet, so try to allocate
-                         * all requested space */
-                        start = block;
-                        end = block + num;
-                } else if (le32_to_cpu(ex->ee_block) > block) {
-                        /* need to allocate space before found extent */
-                        start = block;
-                        end = le32_to_cpu(ex->ee_block);
-                        if (block + num < end)
-                                end = block + num;
-                } else if (block >= le32_to_cpu(ex->ee_block)
-                                        + ext4_ext_get_actual_len(ex)) {
-                        /* need to allocate space after found extent */
-                        start = block;
-                        end = block + num;
-                        if (end >= next)
-                                end = next;
-                } else if (block >= le32_to_cpu(ex->ee_block)) {
-                        /*
-                         * some part of requested space is covered
-                         * by found extent
-                         */
-                        start = block;
-                        end = le32_to_cpu(ex->ee_block)
-                                + ext4_ext_get_actual_len(ex);
-                        if (block + num < end)
-                                end = block + num;
-                        exists = 1;
-                } else {
-                        BUG();
-                }
-                BUG_ON(end <= start);
-
-                if (!exists) {
-                        cbex.ec_block = start;
-                        cbex.ec_len = end - start;
-                        cbex.ec_start = 0;
-                        cbex.ec_type = EXT4_EXT_CACHE_GAP;
-                } else {
-                        cbex.ec_block = le32_to_cpu(ex->ee_block);
-                        cbex.ec_len = ext4_ext_get_actual_len(ex);
-                        cbex.ec_start = ext_pblock(ex);
-                        cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
-                }
-
-                BUG_ON(cbex.ec_len == 0);
-                err = func(inode, path, &cbex, cbdata);
-                ext4_ext_drop_refs(path);
-
-                if (err < 0)
-                        break;
-                if (err == EXT_REPEAT)
-                        continue;
-                else if (err == EXT_BREAK) {
-                        err = 0;
-                        break;
-                }
-
-                if (ext_depth(inode) != depth) {
-                        /* depth was changed. we have to realloc path */
-                        kfree(path);
-                        path = NULL;
-                }
-
-                block = cbex.ec_block + cbex.ec_len;
-        }
-
-        if (path) {
-                ext4_ext_drop_refs(path);
-                kfree(path);
-        }
-
-        return err;
-}
-
 static void
-ext4_ext_put_in_cache(struct inode *inode, __u32 block,
+ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
                         __u32 len, ext4_fsblk_t start, int type)
 {
         struct ext4_ext_cache *cex;
@@ -1561,10 +1460,11 @@ ext4_ext_put_in_cache(struct inode *inode, __u32 block,
  */
 static void
 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
-                                unsigned long block)
+                                ext4_lblk_t block)
 {
         int depth = ext_depth(inode);
-        unsigned long lblock, len;
+        unsigned long len;
+        ext4_lblk_t lblock;
         struct ext4_extent *ex;
 
         ex = path[depth].p_ext;
@@ -1582,15 +1482,17 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
                                 (unsigned long) ext4_ext_get_actual_len(ex));
         } else if (block >= le32_to_cpu(ex->ee_block)
                         + ext4_ext_get_actual_len(ex)) {
+                ext4_lblk_t next;
                 lblock = le32_to_cpu(ex->ee_block)
                         + ext4_ext_get_actual_len(ex);
-                len = ext4_ext_next_allocated_block(path);
+
+                next = ext4_ext_next_allocated_block(path);
                 ext_debug("cache gap(after): [%lu:%lu] %lu",
                                 (unsigned long) le32_to_cpu(ex->ee_block),
                                 (unsigned long) ext4_ext_get_actual_len(ex),
                                 (unsigned long) block);
-                BUG_ON(len == lblock);
-                len = len - lblock;
+                BUG_ON(next == lblock);
+                len = next - lblock;
         } else {
                 lblock = len = 0;
                 BUG();
@@ -1601,7 +1503,7 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
 }
 
 static int
-ext4_ext_in_cache(struct inode *inode, unsigned long block,
+ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
                         struct ext4_extent *ex)
 {
         struct ext4_ext_cache *cex;
@@ -1714,7 +1616,7 @@ int ext4_ext_calc_credits_for_insert(struct inode *inode,
 
 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
                                 struct ext4_extent *ex,
-                                unsigned long from, unsigned long to)
+                                ext4_lblk_t from, ext4_lblk_t to)
 {
         struct buffer_head *bh;
         unsigned short ee_len =  ext4_ext_get_actual_len(ex);
@@ -1738,11 +1640,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
         if (from >= le32_to_cpu(ex->ee_block)
             && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
                 /* tail removal */
-                unsigned long num;
+                ext4_lblk_t num;
                 ext4_fsblk_t start;
+
                 num = le32_to_cpu(ex->ee_block) + ee_len - from;
                 start = ext_pblock(ex) + ee_len - num;
-                ext_debug("free last %lu blocks starting %llu\n", num, start);
+                ext_debug("free last %u blocks starting %llu\n", num, start);
                 for (i = 0; i < num; i++) {
                         bh = sb_find_get_block(inode->i_sb, start + i);
                         ext4_forget(handle, 0, inode, bh, start + i);
@@ -1750,30 +1653,32 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
                 ext4_free_blocks(handle, inode, start, num);
         } else if (from == le32_to_cpu(ex->ee_block)
                    && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
-                printk("strange request: removal %lu-%lu from %u:%u\n",
+                printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
                         from, to, le32_to_cpu(ex->ee_block), ee_len);
         } else {
-                printk("strange request: removal(2) %lu-%lu from %u:%u\n",
-                        from, to, le32_to_cpu(ex->ee_block), ee_len);
+                printk(KERN_INFO "strange request: removal(2) "
+                                "%u-%u from %u:%u\n",
+                                from, to, le32_to_cpu(ex->ee_block), ee_len);
         }
         return 0;
 }
 
 static int
 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
-                struct ext4_ext_path *path, unsigned long start)
+                struct ext4_ext_path *path, ext4_lblk_t start)
 {
         int err = 0, correct_index = 0;
         int depth = ext_depth(inode), credits;
         struct ext4_extent_header *eh;
-        unsigned a, b, block, num;
-        unsigned long ex_ee_block;
+        ext4_lblk_t a, b, block;
+        unsigned num;
+        ext4_lblk_t ex_ee_block;
         unsigned short ex_ee_len;
         unsigned uninitialized = 0;
         struct ext4_extent *ex;
 
         /* the header must be checked already in ext4_ext_remove_space() */
-        ext_debug("truncate since %lu in leaf\n", start);
+        ext_debug("truncate since %u in leaf\n", start);
         if (!path[depth].p_hdr)
                 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
         eh = path[depth].p_hdr;
@@ -1904,7 +1809,7 @@ ext4_ext_more_to_rm(struct ext4_ext_path *path)
         return 1;
 }
 
-int ext4_ext_remove_space(struct inode *inode, unsigned long start)
+int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
 {
         struct super_block *sb = inode->i_sb;
         int depth = ext_depth(inode);
@@ -1912,7 +1817,7 @@ int ext4_ext_remove_space(struct inode *inode, unsigned long start)
         handle_t *handle;
         int i = 0, err = 0;
 
-        ext_debug("truncate since %lu\n", start);
+        ext_debug("truncate since %u\n", start);
 
         /* probably first extent we're gonna free will be last in block */
         handle = ext4_journal_start(inode, depth + 1);
@@ -2094,17 +1999,19 @@ void ext4_ext_release(struct super_block *sb)
  *   b> Splits in two extents: Write is happening at either end of the extent
  *   c> Splits in three extents: Somone is writing in middle of the extent
  */
-int ext4_ext_convert_to_initialized(handle_t *handle, struct inode *inode,
-                                        struct ext4_ext_path *path,
-                                        ext4_fsblk_t iblock,
-                                        unsigned long max_blocks)
+static int ext4_ext_convert_to_initialized(handle_t *handle,
+                                                struct inode *inode,
+                                                struct ext4_ext_path *path,
+                                                ext4_lblk_t iblock,
+                                                unsigned long max_blocks)
 {
         struct ext4_extent *ex, newex;
         struct ext4_extent *ex1 = NULL;
         struct ext4_extent *ex2 = NULL;
         struct ext4_extent *ex3 = NULL;
         struct ext4_extent_header *eh;
-        unsigned int allocated, ee_block, ee_len, depth;
+        ext4_lblk_t ee_block;
+        unsigned int allocated, ee_len, depth;
         ext4_fsblk_t newblock;
         int err = 0;
         int ret = 0;
@@ -2226,7 +2133,7 @@ out:
 }
 
 int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
-                        ext4_fsblk_t iblock,
+                        ext4_lblk_t iblock,
                         unsigned long max_blocks, struct buffer_head *bh_result,
                         int create, int extend_disksize)
 {
@@ -2238,8 +2145,9 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
         unsigned long allocated = 0;
 
         __clear_bit(BH_New, &bh_result->b_state);
-        ext_debug("blocks %d/%lu requested for inode %u\n", (int) iblock,
-                        max_blocks, (unsigned) inode->i_ino);
+        ext_debug("blocks %lu/%lu requested for inode %u\n",
+                        (unsigned long) iblock, max_blocks,
+                        (unsigned) inode->i_ino);
         mutex_lock(&EXT4_I(inode)->truncate_mutex);
 
         /* check in cache */
@@ -2288,7 +2196,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 
         ex = path[depth].p_ext;
         if (ex) {
-                unsigned long ee_block = le32_to_cpu(ex->ee_block);
+                ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
                 ext4_fsblk_t ee_start = ext_pblock(ex);
                 unsigned short ee_len;
 
@@ -2423,7 +2331,7 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
 {
         struct address_space *mapping = inode->i_mapping;
         struct super_block *sb = inode->i_sb;
-        unsigned long last_block;
+        ext4_lblk_t last_block;
         handle_t *handle;
         int err = 0;
 
@@ -2516,7 +2424,8 @@ int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
 long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
 {
         handle_t *handle;
-        ext4_fsblk_t block, max_blocks;
+        ext4_lblk_t block;
+        unsigned long max_blocks;
         ext4_fsblk_t nblocks = 0;
         int ret = 0;
         int ret2 = 0;
@@ -2561,8 +2470,9 @@ retry:
                 if (!ret) {
                         ext4_error(inode->i_sb, "ext4_fallocate",
                                    "ext4_ext_get_blocks returned 0! inode#%lu"
-                                   ", block=%llu, max_blocks=%llu",
-                                   inode->i_ino, block, max_blocks);
+                                   ", block=%lu, max_blocks=%lu",
+                                   inode->i_ino, (unsigned long)block,
+                                   (unsigned long)max_blocks);
                         ret = -EIO;
                         ext4_mark_inode_dirty(handle, inode);
                         ret2 = ext4_journal_stop(handle);