5 files changed, 306 insertions, 62 deletions

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 10bfb466e068..29ff57ec5d1f 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -990,15 +990,6 @@ out:
 }
 
 /*
- * This is only valid for leaf nodes, which are the only ones that can
- * have empty extents anyway.
- */
-static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec)
-{
-        return !rec->e_leaf_clusters;
-}
-
-/*
  * This function will discard the rightmost extent record.
  */
 static void ocfs2_shift_records_right(struct ocfs2_extent_list *el)
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 42ff94bd8011..60cd3d59230c 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -146,4 +146,13 @@ static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el,
                 return le16_to_cpu(rec->e_leaf_clusters);
 }
 
+/*
+ * This is only valid for leaf nodes, which are the only ones that can
+ * have empty extents anyway.
+ */
+static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec)
+{
+        return !rec->e_leaf_clusters;
+}
+
 #endif /* OCFS2_ALLOC_H */
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index c58668a326fe..aed268e80b49 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -25,6 +25,7 @@
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/fiemap.h>
 
 #define MLOG_MASK_PREFIX ML_EXTENT_MAP
 #include <cluster/masklog.h>
@@ -32,6 +33,7 @@
 #include "ocfs2.h"
 
 #include "alloc.h"
+#include "dlmglue.h"
 #include "extent_map.h"
 #include "inode.h"
 #include "super.h"
@@ -282,6 +284,51 @@ out:
                 kfree(new_emi);
 }
 
+static int ocfs2_last_eb_is_empty(struct inode *inode,
+                                  struct ocfs2_dinode *di)
+{
+        int ret, next_free;
+        u64 last_eb_blk = le64_to_cpu(di->i_last_eb_blk);
+        struct buffer_head *eb_bh = NULL;
+        struct ocfs2_extent_block *eb;
+        struct ocfs2_extent_list *el;
+
+        ret = ocfs2_read_block(OCFS2_SB(inode->i_sb), last_eb_blk,
+                               &eb_bh, OCFS2_BH_CACHED, inode);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+        el = &eb->h_list;
+
+        if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
+                ret = -EROFS;
+                OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
+                goto out;
+        }
+
+        if (el->l_tree_depth) {
+                ocfs2_error(inode->i_sb,
+                            "Inode %lu has non zero tree depth in "
+                            "leaf block %llu\n", inode->i_ino,
+                            (unsigned long long)eb_bh->b_blocknr);
+                ret = -EROFS;
+                goto out;
+        }
+
+        next_free = le16_to_cpu(el->l_next_free_rec);
+
+        if (next_free == 0 ||
+            (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0])))
+                ret = 1;
+
+out:
+        brelse(eb_bh);
+        return ret;
+}
+
 /*
  * Return the 1st index within el which contains an extent start
  * larger than v_cluster.
@@ -373,42 +420,28 @@ out:
         return ret;
 }
 
-int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
-                       u32 *p_cluster, u32 *num_clusters,
-                       unsigned int *extent_flags)
+static int ocfs2_get_clusters_nocache(struct inode *inode,
+                                      struct buffer_head *di_bh,
+                                      u32 v_cluster, unsigned int *hole_len,
+                                      struct ocfs2_extent_rec *ret_rec,
+                                      unsigned int *is_last)
 {
-        int ret, i;
-        unsigned int flags = 0;
-        struct buffer_head *di_bh = NULL;
-        struct buffer_head *eb_bh = NULL;
+        int i, ret, tree_height, len;
         struct ocfs2_dinode *di;
-        struct ocfs2_extent_block *eb;
+        struct ocfs2_extent_block *uninitialized_var(eb);
         struct ocfs2_extent_list *el;
         struct ocfs2_extent_rec *rec;
-        u32 coff;
-
-        if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
-                ret = -ERANGE;
-                mlog_errno(ret);
-                goto out;
-        }
-
-        ret = ocfs2_extent_map_lookup(inode, v_cluster, p_cluster,
-                                      num_clusters, extent_flags);
-        if (ret == 0)
-                goto out;
+        struct buffer_head *eb_bh = NULL;
 
-        ret = ocfs2_read_block(OCFS2_SB(inode->i_sb), OCFS2_I(inode)->ip_blkno,
-                               &di_bh, OCFS2_BH_CACHED, inode);
-        if (ret) {
-                mlog_errno(ret);
-                goto out;
-        }
+        memset(ret_rec, 0, sizeof(*ret_rec));
+        if (is_last)
+                *is_last = 0;
 
         di = (struct ocfs2_dinode *) di_bh->b_data;
         el = &di->id2.i_list;
+        tree_height = le16_to_cpu(el->l_tree_depth);
 
-        if (el->l_tree_depth) {
+        if (tree_height > 0) {
                 ret = ocfs2_find_leaf(inode, el, v_cluster, &eb_bh);
                 if (ret) {
                         mlog_errno(ret);
@@ -431,46 +464,143 @@ int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
         i = ocfs2_search_extent_list(el, v_cluster);
         if (i == -1) {
                 /*
-                 * A hole was found. Return some canned values that
-                 * callers can key on. If asked for, num_clusters will
-                 * be populated with the size of the hole.
+                 * Holes can be larger than the maximum size of an
+                 * extent, so we return their lengths in a seperate
+                 * field.
                  */
-                *p_cluster = 0;
-                if (num_clusters) {
+                if (hole_len) {
                         ret = ocfs2_figure_hole_clusters(inode, el, eb_bh,
-                                                         v_cluster,
-                                                         num_clusters);
+                                                         v_cluster, &len);
                         if (ret) {
                                 mlog_errno(ret);
                                 goto out;
                         }
+
+                        *hole_len = len;
                 }
-        } else {
-                rec = &el->l_recs[i];
+                goto out_hole;
+        }
 
-                BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
+        rec = &el->l_recs[i];
 
-                if (!rec->e_blkno) {
-                        ocfs2_error(inode->i_sb, "Inode %lu has bad extent "
-                                    "record (%u, %u, 0)", inode->i_ino,
-                                    le32_to_cpu(rec->e_cpos),
-                                    ocfs2_rec_clusters(el, rec));
-                        ret = -EROFS;
-                        goto out;
+        BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos));
+
+        if (!rec->e_blkno) {
+                ocfs2_error(inode->i_sb, "Inode %lu has bad extent "
+                            "record (%u, %u, 0)", inode->i_ino,
+                            le32_to_cpu(rec->e_cpos),
+                            ocfs2_rec_clusters(el, rec));
+                ret = -EROFS;
+                goto out;
+        }
+
+        *ret_rec = *rec;
+
+        /*
+         * Checking for last extent is potentially expensive - we
+         * might have to look at the next leaf over to see if it's
+         * empty.
+         *
+         * The first two checks are to see whether the caller even
+         * cares for this information, and if the extent is at least
+         * the last in it's list.
+         *
+         * If those hold true, then the extent is last if any of the
+         * additional conditions hold true:
+         *  - Extent list is in-inode
+         *  - Extent list is right-most
+         *  - Extent list is 2nd to rightmost, with empty right-most
+         */
+        if (is_last) {
+                if (i == (le16_to_cpu(el->l_next_free_rec) - 1)) {
+                        if (tree_height == 0)
+                                *is_last = 1;
+                        else if (eb->h_blkno == di->i_last_eb_blk)
+                                *is_last = 1;
+                        else if (eb->h_next_leaf_blk == di->i_last_eb_blk) {
+                                ret = ocfs2_last_eb_is_empty(inode, di);
+                                if (ret < 0) {
+                                        mlog_errno(ret);
+                                        goto out;
+                                }
+                                if (ret == 1)
+                                        *is_last = 1;
+                        }
                 }
+        }
+
+out_hole:
+        ret = 0;
+out:
+        brelse(eb_bh);
+        return ret;
+}
+
+static void ocfs2_relative_extent_offsets(struct super_block *sb,
+                                          u32 v_cluster,
+                                          struct ocfs2_extent_rec *rec,
+                                          u32 *p_cluster, u32 *num_clusters)
+
+{
+        u32 coff = v_cluster - le32_to_cpu(rec->e_cpos);
+
+        *p_cluster = ocfs2_blocks_to_clusters(sb, le64_to_cpu(rec->e_blkno));
+        *p_cluster = *p_cluster + coff;
+
+        if (num_clusters)
+                *num_clusters = le16_to_cpu(rec->e_leaf_clusters) - coff;
+}
+
+int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
+                       u32 *p_cluster, u32 *num_clusters,
+                       unsigned int *extent_flags)
+{
+        int ret;
+        unsigned int uninitialized_var(hole_len), flags = 0;
+        struct buffer_head *di_bh = NULL;
+        struct ocfs2_extent_rec rec;
 
-                coff = v_cluster - le32_to_cpu(rec->e_cpos);
+        if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+                ret = -ERANGE;
+                mlog_errno(ret);
+                goto out;
+        }
 
-                *p_cluster = ocfs2_blocks_to_clusters(inode->i_sb,
-                                                    le64_to_cpu(rec->e_blkno));
-                *p_cluster = *p_cluster + coff;
+        ret = ocfs2_extent_map_lookup(inode, v_cluster, p_cluster,
+                                      num_clusters, extent_flags);
+        if (ret == 0)
+                goto out;
 
-                if (num_clusters)
-                        *num_clusters = ocfs2_rec_clusters(el, rec) - coff;
+        ret = ocfs2_read_block(OCFS2_SB(inode->i_sb), OCFS2_I(inode)->ip_blkno,
+                               &di_bh, OCFS2_BH_CACHED, inode);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
 
-                flags = rec->e_flags;
+        ret = ocfs2_get_clusters_nocache(inode, di_bh, v_cluster, &hole_len,
+                                         &rec, NULL);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
 
-                ocfs2_extent_map_insert_rec(inode, rec);
+        if (rec.e_blkno == 0ULL) {
+                /*
+                 * A hole was found. Return some canned values that
+                 * callers can key on. If asked for, num_clusters will
+                 * be populated with the size of the hole.
+                 */
+                *p_cluster = 0;
+                if (num_clusters) {
+                        *num_clusters = hole_len;
+                }
+        } else {
+                ocfs2_relative_extent_offsets(inode->i_sb, v_cluster, &rec,
+                                              p_cluster, num_clusters);
+                flags = rec.e_flags;
+
+                ocfs2_extent_map_insert_rec(inode, &rec);
         }
 
         if (extent_flags)
@@ -478,7 +608,6 @@ int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
 
 out:
         brelse(di_bh);
-        brelse(eb_bh);
         return ret;
 }
 
@@ -521,3 +650,114 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
 out:
         return ret;
 }
+
+static int ocfs2_fiemap_inline(struct inode *inode, struct buffer_head *di_bh,
+                               struct fiemap_extent_info *fieinfo,
+                               u64 map_start)
+{
+        int ret;
+        unsigned int id_count;
+        struct ocfs2_dinode *di;
+        u64 phys;
+        u32 flags = FIEMAP_EXTENT_DATA_INLINE|FIEMAP_EXTENT_LAST;
+        struct ocfs2_inode_info *oi = OCFS2_I(inode);
+
+        di = (struct ocfs2_dinode *)di_bh->b_data;
+        id_count = le16_to_cpu(di->id2.i_data.id_count);
+
+        if (map_start < id_count) {
+                phys = oi->ip_blkno << inode->i_sb->s_blocksize_bits;
+                phys += offsetof(struct ocfs2_dinode, id2.i_data.id_data);
+
+                ret = fiemap_fill_next_extent(fieinfo, 0, phys, id_count,
+                                              flags);
+                if (ret < 0)
+                        return ret;
+        }
+
+        return 0;
+}
+
+#define OCFS2_FIEMAP_FLAGS      (FIEMAP_FLAG_SYNC)
+
+int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+                 u64 map_start, u64 map_len)
+{
+        int ret, is_last;
+        u32 mapping_end, cpos;
+        unsigned int hole_size;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+        u64 len_bytes, phys_bytes, virt_bytes;
+        struct buffer_head *di_bh = NULL;
+        struct ocfs2_extent_rec rec;
+
+        ret = fiemap_check_flags(fieinfo, OCFS2_FIEMAP_FLAGS);
+        if (ret)
+                return ret;
+
+        ret = ocfs2_inode_lock(inode, &di_bh, 0);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        down_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+        /*
+         * Handle inline-data separately.
+         */
+        if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+                ret = ocfs2_fiemap_inline(inode, di_bh, fieinfo, map_start);
+                goto out_unlock;
+        }
+
+        cpos = map_start >> osb->s_clustersize_bits;
+        mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
+                                               map_start + map_len);
+        mapping_end -= cpos;
+        is_last = 0;
+        while (cpos < mapping_end && !is_last) {
+                u32 fe_flags;
+
+                ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
+                                                 &hole_size, &rec, &is_last);
+                if (ret) {
+                        mlog_errno(ret);
+                        goto out;
+                }
+
+                if (rec.e_blkno == 0ULL) {
+                        cpos += hole_size;
+                        continue;
+                }
+
+                fe_flags = 0;
+                if (rec.e_flags & OCFS2_EXT_UNWRITTEN)
+                        fe_flags |= FIEMAP_EXTENT_UNWRITTEN;
+                if (is_last)
+                        fe_flags |= FIEMAP_EXTENT_LAST;
+                len_bytes = (u64)le16_to_cpu(rec.e_leaf_clusters) << osb->s_clustersize_bits;
+                phys_bytes = le64_to_cpu(rec.e_blkno) << osb->sb->s_blocksize_bits;
+                virt_bytes = (u64)le32_to_cpu(rec.e_cpos) << osb->s_clustersize_bits;
+
+                ret = fiemap_fill_next_extent(fieinfo, virt_bytes, phys_bytes,
+                                              len_bytes, fe_flags);
+                if (ret)
+                        break;
+
+                cpos = le32_to_cpu(rec.e_cpos)+ le16_to_cpu(rec.e_leaf_clusters);
+        }
+
+        if (ret > 0)
+                ret = 0;
+
+out_unlock:
+        brelse(di_bh);
+
+        up_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+        ocfs2_inode_unlock(inode, 0);
+out:
+
+        return ret;
+}
diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h
index de91e3e41a22..1b97490e1ea8 100644
--- a/fs/ocfs2/extent_map.h
+++ b/fs/ocfs2/extent_map.h
@@ -50,4 +50,7 @@ int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, u32 *p_cluster,
 int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
                                 u64 *ret_count, unsigned int *extent_flags);
 
+int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+                 u64 map_start, u64 map_len);
+
 #endif  /* _EXTENT_MAP_H */
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index ec2ed15c3daa..ed38796052d2 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2228,6 +2228,7 @@ const struct inode_operations ocfs2_file_iops = {
         .getattr        = ocfs2_getattr,
         .permission     = ocfs2_permission,
         .fallocate      = ocfs2_fallocate,
+        .fiemap         = ocfs2_fiemap,
 };
 
 const struct inode_operations ocfs2_special_file_iops = {