[PATCH] io-accounting: write-cancel accounting

[pandora-kernel.git] / fs / buffer.c

diff --git a/fs/buffer.c b/fs/buffer.c
index 16cfbcd..d1f1b54 100644 (file)
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -35,6 +35,7 @@
 #include <linux/hash.h>
 #include <linux/suspend.h>
 #include <linux/buffer_head.h>
+#include <linux/task_io_accounting_ops.h>
 #include <linux/bio.h>
 #include <linux/notifier.h>
 #include <linux/cpu.h>
@@ -452,6 +453,7 @@ static void end_buffer_async_write(struct buffer_head *bh, int uptodate)
                               bdevname(bh->b_bdev, b));
                }
                set_bit(AS_EIO, &page->mapping->flags);
+               set_buffer_write_io_error(bh);
                clear_buffer_uptodate(bh);
                SetPageError(page);
        }
@@ -571,6 +573,10 @@ EXPORT_SYMBOL(mark_buffer_async_write);
 static inline void __remove_assoc_queue(struct buffer_head *bh)
 {
        list_del_init(&bh->b_assoc_buffers);
+       WARN_ON(!bh->b_assoc_map);
+       if (buffer_write_io_error(bh))
+               set_bit(AS_EIO, &bh->b_assoc_map->flags);
+       bh->b_assoc_map = NULL;
 }
 
 int inode_has_buffers(struct inode *inode)
@@ -669,6 +675,7 @@ void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode)
                spin_lock(&buffer_mapping->private_lock);
                list_move_tail(&bh->b_assoc_buffers,
                                &mapping->private_list);
+               bh->b_assoc_map = mapping;
                spin_unlock(&buffer_mapping->private_lock);
        }
 }
@@ -701,7 +708,10 @@ EXPORT_SYMBOL(mark_buffer_dirty_inode);
  */
 int __set_page_dirty_buffers(struct page *page)
 {
-       struct address_space * const mapping = page->mapping;
+       struct address_space * const mapping = page_mapping(page);
+
+       if (unlikely(!mapping))
+               return !TestSetPageDirty(page);
 
        spin_lock(&mapping->private_lock);
        if (page_has_buffers(page)) {
@@ -715,20 +725,21 @@ int __set_page_dirty_buffers(struct page *page)
        }
        spin_unlock(&mapping->private_lock);
 
-       if (!TestSetPageDirty(page)) {
-               write_lock_irq(&mapping->tree_lock);
-               if (page->mapping) {    /* Race with truncate? */
-                       if (mapping_cap_account_dirty(mapping))
-                               __inc_zone_page_state(page, NR_FILE_DIRTY);
-                       radix_tree_tag_set(&mapping->page_tree,
-                                               page_index(page),
-                                               PAGECACHE_TAG_DIRTY);
+       if (TestSetPageDirty(page))
+               return 0;
+
+       write_lock_irq(&mapping->tree_lock);
+       if (page->mapping) {    /* Race with truncate? */
+               if (mapping_cap_account_dirty(mapping)) {
+                       __inc_zone_page_state(page, NR_FILE_DIRTY);
+                       task_io_account_write(PAGE_CACHE_SIZE);
                }
-               write_unlock_irq(&mapping->tree_lock);
-               __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
-               return 1;
+               radix_tree_tag_set(&mapping->page_tree,
+                               page_index(page), PAGECACHE_TAG_DIRTY);
        }
-       return 0;
+       write_unlock_irq(&mapping->tree_lock);
+       __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
+       return 1;
 }
 EXPORT_SYMBOL(__set_page_dirty_buffers);
 
@@ -762,7 +773,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
        spin_lock(lock);
        while (!list_empty(list)) {
                bh = BH_ENTRY(list->next);
-               list_del_init(&bh->b_assoc_buffers);
+               __remove_assoc_queue(bh);
                if (buffer_dirty(bh) || buffer_locked(bh)) {
                        list_add(&bh->b_assoc_buffers, &tmp);
                        if (buffer_dirty(bh)) {
@@ -783,7 +794,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list)
 
        while (!list_empty(&tmp)) {
                bh = BH_ENTRY(tmp.prev);
-               __remove_assoc_queue(bh);
+               list_del_init(&bh->b_assoc_buffers);
                get_bh(bh);
                spin_unlock(lock);
                wait_on_buffer(bh);
@@ -1039,8 +1050,21 @@ grow_buffers(struct block_device *bdev, sector_t block, int size)
        } while ((size << sizebits) < PAGE_SIZE);
 
        index = block >> sizebits;
-       block = index << sizebits;
 
+       /*
+        * Check for a block which wants to lie outside our maximum possible
+        * pagecache index.  (this comparison is done using sector_t types).
+        */
+       if (unlikely(index != block >> sizebits)) {
+               char b[BDEVNAME_SIZE];
+
+               printk(KERN_ERR "%s: requested out-of-range block %llu for "
+                       "device %s\n",
+                       __FUNCTION__, (unsigned long long)block,
+                       bdevname(bdev, b));
+               return -EIO;
+       }
+       block = index << sizebits;
        /* Create a page with the proper size buffers.. */
        page = grow_dev_page(bdev, block, index, size);
        if (!page)
@@ -1067,12 +1091,16 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size)
 
        for (;;) {
                struct buffer_head * bh;
+               int ret;
 
                bh = __find_get_block(bdev, block, size);
                if (bh)
                        return bh;
 
-               if (!grow_buffers(bdev, block, size))
+               ret = grow_buffers(bdev, block, size);
+               if (ret < 0)
+                       return NULL;
+               if (ret == 0)
                        free_more_memory();
        }
 }
@@ -1147,6 +1175,7 @@ void __bforget(struct buffer_head *bh)
 
                spin_lock(&buffer_mapping->private_lock);
                list_del_init(&bh->b_assoc_buffers);
+               bh->b_assoc_map = NULL;
                spin_unlock(&buffer_mapping->private_lock);
        }
        __brelse(bh);
@@ -1834,6 +1863,7 @@ static int __block_prepare_write(struct inode *inode, struct page *page,
                        clear_buffer_new(bh);
                        kaddr = kmap_atomic(page, KM_USER0);
                        memset(kaddr+block_start, 0, bh->b_size);
+                       flush_dcache_page(page);
                        kunmap_atomic(kaddr, KM_USER0);
                        set_buffer_uptodate(bh);
                        mark_buffer_dirty(bh);
@@ -2340,6 +2370,7 @@ failed:
         */
        kaddr = kmap_atomic(page, KM_USER0);
        memset(kaddr, 0, PAGE_CACHE_SIZE);
+       flush_dcache_page(page);
        kunmap_atomic(kaddr, KM_USER0);
        SetPageUptodate(page);
        set_page_dirty(page);
@@ -2822,8 +2853,13 @@ int try_to_free_buffers(struct page *page)
                 * could encounter a non-uptodate page, which is unresolvable.
                 * This only applies in the rare case where try_to_free_buffers
                 * succeeds but the page is not freed.
+                *
+                * Also, during truncate, discard_buffer will have marked all
+                * the page's buffers clean.  We discover that here and clean
+                * the page also.
                 */
-               clear_page_dirty(page);
+               if (test_clear_page_dirty(page))
+                       task_io_account_cancelled_write(PAGE_CACHE_SIZE);
        }
 out:
        if (buffers_to_free) {
@@ -2879,7 +2915,7 @@ asmlinkage long sys_bdflush(int func, long data)
 /*
  * Buffer-head allocation
  */
-static kmem_cache_t *bh_cachep;
+static struct kmem_cache *bh_cachep;
 
 /*
  * Once the number of bh's in the machine exceeds this level, we start
@@ -2932,7 +2968,7 @@ void free_buffer_head(struct buffer_head *bh)
 EXPORT_SYMBOL(free_buffer_head);
 
 static void
-init_buffer_head(void *data, kmem_cache_t *cachep, unsigned long flags)
+init_buffer_head(void *data, struct kmem_cache *cachep, unsigned long flags)
 {
        if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
                            SLAB_CTOR_CONSTRUCTOR) {
@@ -2943,7 +2979,6 @@ init_buffer_head(void *data, kmem_cache_t *cachep, unsigned long flags)
        }
 }
 
-#ifdef CONFIG_HOTPLUG_CPU
 static void buffer_exit_cpu(int cpu)
 {
        int i;
@@ -2965,7 +3000,6 @@ static int buffer_cpu_notify(struct notifier_block *self,
                buffer_exit_cpu((unsigned long)hcpu);
        return NOTIFY_OK;
 }
-#endif /* CONFIG_HOTPLUG_CPU */
 
 void __init buffer_init(void)
 {