[PATCH] Add missing overflow check in get_blkdev_list

[linux-2.6] / fs / buffer.c

diff --git a/fs/buffer.c b/fs/buffer.c
index 12bdb27911271202174ba43abcc789ed7eefccf0..6a25d7df89b176db6bb7163517538476398a9af4 100644 (file)
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -278,7 +278,7 @@ EXPORT_SYMBOL(thaw_bdev);
  */
 static void do_sync(unsigned long wait)
 {
-       wakeup_bdflush(0);
+       wakeup_pdflush(0);
        sync_inodes(0);         /* All mappings, inodes and their blockdevs */
        DQUOT_SYNC(NULL);
        sync_supers();          /* Write the superblocks */
@@ -497,7 +497,7 @@ static void free_more_memory(void)
        struct zone **zones;
        pg_data_t *pgdat;
 
-       wakeup_bdflush(1024);
+       wakeup_pdflush(1024);
        yield();
 
        for_each_pgdat(pgdat) {
@@ -513,8 +513,8 @@ static void free_more_memory(void)
  */
 static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
 {
-       static DEFINE_SPINLOCK(page_uptodate_lock);
        unsigned long flags;
+       struct buffer_head *first;
        struct buffer_head *tmp;
        struct page *page;
        int page_uptodate = 1;
@@ -536,7 +536,9 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
         * two buffer heads end IO at almost the same time and both
         * decide that the page is now completely done.
         */
-       spin_lock_irqsave(&page_uptodate_lock, flags);
+       first = page_buffers(page);
+       local_irq_save(flags);
+       bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
        clear_buffer_async_read(bh);
        unlock_buffer(bh);
        tmp = bh;
@@ -549,7 +551,8 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
                }
                tmp = tmp->b_this_page;
        } while (tmp != bh);
-       spin_unlock_irqrestore(&page_uptodate_lock, flags);
+       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+       local_irq_restore(flags);
 
        /*
         * If none of the buffers had errors and they are all
@@ -561,7 +564,8 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
        return;
 
 still_busy:
-       spin_unlock_irqrestore(&page_uptodate_lock, flags);
+       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+       local_irq_restore(flags);
        return;
 }
 
@@ -572,8 +576,8 @@ still_busy:
 void end_buffer_async_write(struct buffer_head *bh, int uptodate)
 {
        char b[BDEVNAME_SIZE];
-       static DEFINE_SPINLOCK(page_uptodate_lock);
        unsigned long flags;
+       struct buffer_head *first;
        struct buffer_head *tmp;
        struct page *page;
 
@@ -594,7 +598,10 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
                SetPageError(page);
        }
 
-       spin_lock_irqsave(&page_uptodate_lock, flags);
+       first = page_buffers(page);
+       local_irq_save(flags);
+       bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
+
        clear_buffer_async_write(bh);
        unlock_buffer(bh);
        tmp = bh->b_this_page;
@@ -605,12 +612,14 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
                }
                tmp = tmp->b_this_page;
        }
-       spin_unlock_irqrestore(&page_uptodate_lock, flags);
+       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+       local_irq_restore(flags);
        end_page_writeback(page);
        return;
 
 still_busy:
-       spin_unlock_irqrestore(&page_uptodate_lock, flags);
+       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+       local_irq_restore(flags);
        return;
 }
 
@@ -1926,7 +1935,6 @@ static int __block_prepare_write(struct inode *inode, struct page *page,
                        if (err)
                                break;
                        if (buffer_new(bh)) {
-                               clear_buffer_new(bh);
                                unmap_underlying_metadata(bh->b_bdev,
                                                        bh->b_blocknr);
                                if (PageUptodate(page)) {
@@ -1968,9 +1976,14 @@ static int __block_prepare_write(struct inode *inode, struct page *page,
                if (!buffer_uptodate(*wait_bh))
                        err = -EIO;
        }
-       if (!err)
-               return err;
-
+       if (!err) {
+               bh = head;
+               do {
+                       if (buffer_new(bh))
+                               clear_buffer_new(bh);
+               } while ((bh = bh->b_this_page) != head);
+               return 0;
+       }
        /* Error case: */
        /*
         * Zero out any newly allocated blocks to avoid exposing stale