1 files changed, 29 insertions, 33 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 456c9ab7705b..826baf4f04bc 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1798,7 +1798,7 @@ void page_zero_new_buffers(struct page *page, unsigned from, unsigned to)
                                         start = max(from, block_start);
                                         size = min(to, block_end) - start;
 
-                                        zero_user_page(page, start, size, KM_USER0);
+                                        zero_user(page, start, size);
                                         set_buffer_uptodate(bh);
                                 }
 
@@ -1861,19 +1861,10 @@ static int __block_prepare_write(struct inode *inode, struct page *page,
                                         mark_buffer_dirty(bh);
                                         continue;
                                 }
-                                if (block_end > to || block_start < from) {
-                                        void *kaddr;
-
-                                        kaddr = kmap_atomic(page, KM_USER0);
-                                        if (block_end > to)
-                                                memset(kaddr+to, 0,
-                                                        block_end-to);
-                                        if (block_start < from)
-                                                memset(kaddr+block_start,
-                                                        0, from-block_start);
-                                        flush_dcache_page(page);
-                                        kunmap_atomic(kaddr, KM_USER0);
-                                }
+                                if (block_end > to || block_start < from)
+                                        zero_user_segments(page,
+                                                to, block_end,
+                                                block_start, from);
                                 continue;
                         }
                 }
@@ -2104,8 +2095,7 @@ int block_read_full_page(struct page *page, get_block_t *get_block)
                                         SetPageError(page);
                         }
                         if (!buffer_mapped(bh)) {
-                                zero_user_page(page, i * blocksize, blocksize,
-                                                KM_USER0);
+                                zero_user(page, i * blocksize, blocksize);
                                 if (!err)
                                         set_buffer_uptodate(bh);
                                 continue;
@@ -2218,7 +2208,7 @@ int cont_expand_zero(struct file *file, struct address_space *mapping,
                                                 &page, &fsdata);
                 if (err)
                         goto out;
-                zero_user_page(page, zerofrom, len, KM_USER0);
+                zero_user(page, zerofrom, len);
                 err = pagecache_write_end(file, mapping, curpos, len, len,
                                                 page, fsdata);
                 if (err < 0)
@@ -2245,7 +2235,7 @@ int cont_expand_zero(struct file *file, struct address_space *mapping,
                                                 &page, &fsdata);
                 if (err)
                         goto out;
-                zero_user_page(page, zerofrom, len, KM_USER0);
+                zero_user(page, zerofrom, len);
                 err = pagecache_write_end(file, mapping, curpos, len, len,
                                                 page, fsdata);
                 if (err < 0)
@@ -2422,7 +2412,6 @@ int nobh_write_begin(struct file *file, struct address_space *mapping,
         unsigned block_in_page;
         unsigned block_start, block_end;
         sector_t block_in_file;
-        char *kaddr;
         int nr_reads = 0;
         int ret = 0;
         int is_mapped_to_disk = 1;
@@ -2493,13 +2482,8 @@ int nobh_write_begin(struct file *file, struct address_space *mapping,
                         continue;
                 }
                 if (buffer_new(bh) || !buffer_mapped(bh)) {
-                        kaddr = kmap_atomic(page, KM_USER0);
-                        if (block_start < from)
-                                memset(kaddr+block_start, 0, from-block_start);
-                        if (block_end > to)
-                                memset(kaddr + to, 0, block_end - to);
-                        flush_dcache_page(page);
-                        kunmap_atomic(kaddr, KM_USER0);
+                        zero_user_segments(page, block_start, from,
+                                                        to, block_end);
                         continue;
                 }
                 if (buffer_uptodate(bh))
@@ -2636,7 +2620,7 @@ int nobh_writepage(struct page *page, get_block_t *get_block,
          * the  page size, the remaining memory is zeroed when mapped, and
          * writes to that region are not written out to the file."
          */
-        zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+        zero_user_segment(page, offset, PAGE_CACHE_SIZE);
 out:
         ret = mpage_writepage(page, get_block, wbc);
         if (ret == -EAGAIN)
@@ -2709,7 +2693,7 @@ has_buffers:
                 if (page_has_buffers(page))
                         goto has_buffers;
         }
-        zero_user_page(page, offset, length, KM_USER0);
+        zero_user(page, offset, length);
         set_page_dirty(page);
         err = 0;
 
@@ -2785,7 +2769,7 @@ int block_truncate_page(struct address_space *mapping,
                         goto unlock;
         }
 
-        zero_user_page(page, offset, length, KM_USER0);
+        zero_user(page, offset, length);
         mark_buffer_dirty(bh);
         err = 0;
 
@@ -2831,7 +2815,7 @@ int block_write_full_page(struct page *page, get_block_t *get_block,
          * the  page size, the remaining memory is zeroed when mapped, and
          * writes to that region are not written out to the file."
          */
-        zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+        zero_user_segment(page, offset, PAGE_CACHE_SIZE);
         return __block_write_full_page(inode, page, get_block, wbc);
 }
 
@@ -3169,7 +3153,7 @@ static void recalc_bh_state(void)
         
 struct buffer_head *alloc_buffer_head(gfp_t gfp_flags)
 {
-        struct buffer_head *ret = kmem_cache_zalloc(bh_cachep,
+        struct buffer_head *ret = kmem_cache_alloc(bh_cachep,
                                 set_migrateflags(gfp_flags, __GFP_RECLAIMABLE));
         if (ret) {
                 INIT_LIST_HEAD(&ret->b_assoc_buffers);
@@ -3257,12 +3241,24 @@ int bh_submit_read(struct buffer_head *bh)
 }
 EXPORT_SYMBOL(bh_submit_read);
 
+static void
+init_buffer_head(struct kmem_cache *cachep, void *data)
+{
+        struct buffer_head *bh = data;
+
+        memset(bh, 0, sizeof(*bh));
+        INIT_LIST_HEAD(&bh->b_assoc_buffers);
+}
+
 void __init buffer_init(void)
 {
         int nrpages;
 
-        bh_cachep = KMEM_CACHE(buffer_head,
-                        SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|SLAB_MEM_SPREAD);
+        bh_cachep = kmem_cache_create("buffer_head",
+                        sizeof(struct buffer_head), 0,
+                                (SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|
+                                SLAB_MEM_SPREAD),
+                                init_buffer_head);
 
         /*
          * Limit the bh occupancy to 10% of ZONE_NORMAL