Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux...

[safe/jmp/linux-2.6] / fs / nilfs2 / alloc.c

diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c
index d69e6ae..3f959f1 100644 (file)
--- a/fs/nilfs2/alloc.c
+++ b/fs/nilfs2/alloc.c
@@ -142,29 +142,75 @@ static void nilfs_palloc_desc_block_init(struct inode *inode,
        }
 }
 
+static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff,
+                                 int create,
+                                 void (*init_block)(struct inode *,
+                                                    struct buffer_head *,
+                                                    void *),
+                                 struct buffer_head **bhp,
+                                 struct nilfs_bh_assoc *prev,
+                                 spinlock_t *lock)
+{
+       int ret;
+
+       spin_lock(lock);
+       if (prev->bh && blkoff == prev->blkoff) {
+               get_bh(prev->bh);
+               *bhp = prev->bh;
+               spin_unlock(lock);
+               return 0;
+       }
+       spin_unlock(lock);
+
+       ret = nilfs_mdt_get_block(inode, blkoff, create, init_block, bhp);
+       if (!ret) {
+               spin_lock(lock);
+               /*
+                * The following code must be safe for change of the
+                * cache contents during the get block call.
+                */
+               brelse(prev->bh);
+               get_bh(*bhp);
+               prev->bh = *bhp;
+               prev->blkoff = blkoff;
+               spin_unlock(lock);
+       }
+       return ret;
+}
+
 static int nilfs_palloc_get_desc_block(struct inode *inode,
                                       unsigned long group,
                                       int create, struct buffer_head **bhp)
 {
-       return nilfs_mdt_get_block(inode,
-                                  nilfs_palloc_desc_blkoff(inode, group),
-                                  create, nilfs_palloc_desc_block_init, bhp);
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       return nilfs_palloc_get_block(inode,
+                                     nilfs_palloc_desc_blkoff(inode, group),
+                                     create, nilfs_palloc_desc_block_init,
+                                     bhp, &cache->prev_desc, &cache->lock);
 }
 
 static int nilfs_palloc_get_bitmap_block(struct inode *inode,
                                         unsigned long group,
                                         int create, struct buffer_head **bhp)
 {
-       return nilfs_mdt_get_block(inode,
-                                  nilfs_palloc_bitmap_blkoff(inode, group),
-                                  create, NULL, bhp);
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       return nilfs_palloc_get_block(inode,
+                                     nilfs_palloc_bitmap_blkoff(inode, group),
+                                     create, NULL, bhp,
+                                     &cache->prev_bitmap, &cache->lock);
 }
 
 int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr,
                                 int create, struct buffer_head **bhp)
 {
-       return nilfs_mdt_get_block(inode, nilfs_palloc_entry_blkoff(inode, nr),
-                                  create, NULL, bhp);
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       return nilfs_palloc_get_block(inode,
+                                     nilfs_palloc_entry_blkoff(inode, nr),
+                                     create, NULL, bhp,
+                                     &cache->prev_entry, &cache->lock);
 }
 
 static struct nilfs_palloc_group_desc *
@@ -176,13 +222,6 @@ nilfs_palloc_block_get_group_desc(const struct inode *inode,
                group % nilfs_palloc_groups_per_desc_block(inode);
 }
 
-static unsigned char *
-nilfs_palloc_block_get_bitmap(const struct inode *inode,
-                             const struct buffer_head *bh, void *kaddr)
-{
-       return (unsigned char *)(kaddr + bh_offset(bh));
-}
-
 void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr,
                                   const struct buffer_head *bh, void *kaddr)
 {
@@ -289,8 +328,7 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode,
                                if (ret < 0)
                                        goto out_desc;
                                bitmap_kaddr = kmap(bitmap_bh->b_page);
-                               bitmap = nilfs_palloc_block_get_bitmap(
-                                       inode, bitmap_bh, bitmap_kaddr);
+                               bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
                                pos = nilfs_palloc_find_available_slot(
                                        inode, group, group_offset, bitmap,
                                        entries_per_group);
@@ -351,8 +389,7 @@ void nilfs_palloc_commit_free_entry(struct inode *inode,
        desc = nilfs_palloc_block_get_group_desc(inode, group,
                                                 req->pr_desc_bh, desc_kaddr);
        bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page);
-       bitmap = nilfs_palloc_block_get_bitmap(inode, req->pr_bitmap_bh,
-                                              bitmap_kaddr);
+       bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
 
        if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group),
                                    group_offset, bitmap))
@@ -385,8 +422,7 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode,
        desc = nilfs_palloc_block_get_group_desc(inode, group,
                                                 req->pr_desc_bh, desc_kaddr);
        bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page);
-       bitmap = nilfs_palloc_block_get_bitmap(inode, req->pr_bitmap_bh,
-                                              bitmap_kaddr);
+       bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
        if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group),
                                    group_offset, bitmap))
                printk(KERN_WARNING "%s: entry numer %llu already freed\n",
@@ -472,8 +508,7 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
                desc = nilfs_palloc_block_get_group_desc(
                        inode, group, desc_bh, desc_kaddr);
                bitmap_kaddr = kmap(bitmap_bh->b_page);
-               bitmap = nilfs_palloc_block_get_bitmap(
-                       inode, bitmap_bh, bitmap_kaddr);
+               bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
                for (j = i, n = 0;
                     (j < nitems) && nilfs_palloc_group_is_in(inode, group,
                                                              entry_nrs[j]);
@@ -502,3 +537,30 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
        }
        return 0;
 }
+
+void nilfs_palloc_setup_cache(struct inode *inode,
+                             struct nilfs_palloc_cache *cache)
+{
+       NILFS_MDT(inode)->mi_palloc_cache = cache;
+       spin_lock_init(&cache->lock);
+}
+
+void nilfs_palloc_clear_cache(struct inode *inode)
+{
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       spin_lock(&cache->lock);
+       brelse(cache->prev_desc.bh);
+       brelse(cache->prev_bitmap.bh);
+       brelse(cache->prev_entry.bh);
+       cache->prev_desc.bh = NULL;
+       cache->prev_bitmap.bh = NULL;
+       cache->prev_entry.bh = NULL;
+       spin_unlock(&cache->lock);
+}
+
+void nilfs_palloc_destroy_cache(struct inode *inode)
+{
+       nilfs_palloc_clear_cache(inode);
+       NILFS_MDT(inode)->mi_palloc_cache = NULL;
+}