summaryrefslogtreecommitdiffstats
path: root/fs/buffer.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/buffer.c')
-rw-r--r--fs/buffer.c55
1 files changed, 50 insertions, 5 deletions
diff --git a/fs/buffer.c b/fs/buffer.c
index d48caee..ca12a6b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -706,7 +706,7 @@ static int __set_page_dirty(struct page *page,
if (TestSetPageDirty(page))
return 0;
- write_lock_irq(&mapping->tree_lock);
+ spin_lock_irq(&mapping->tree_lock);
if (page->mapping) { /* Race with truncate? */
WARN_ON_ONCE(warn && !PageUptodate(page));
@@ -719,7 +719,7 @@ static int __set_page_dirty(struct page *page,
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
- write_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irq(&mapping->tree_lock);
__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
return 1;
@@ -1214,8 +1214,7 @@ void __brelse(struct buffer_head * buf)
put_bh(buf);
return;
}
- printk(KERN_ERR "VFS: brelse: Trying to free free buffer\n");
- WARN_ON(1);
+ WARN(1, KERN_ERR "VFS: brelse: Trying to free free buffer\n");
}
/*
@@ -2097,6 +2096,52 @@ int generic_write_end(struct file *file, struct address_space *mapping,
EXPORT_SYMBOL(generic_write_end);
/*
+ * block_is_partially_uptodate checks whether buffers within a page are
+ * uptodate or not.
+ *
+ * Returns true if all buffers which correspond to a file portion
+ * we want to read are uptodate.
+ */
+int block_is_partially_uptodate(struct page *page, read_descriptor_t *desc,
+ unsigned long from)
+{
+ struct inode *inode = page->mapping->host;
+ unsigned block_start, block_end, blocksize;
+ unsigned to;
+ struct buffer_head *bh, *head;
+ int ret = 1;
+
+ if (!page_has_buffers(page))
+ return 0;
+
+ blocksize = 1 << inode->i_blkbits;
+ to = min_t(unsigned, PAGE_CACHE_SIZE - from, desc->count);
+ to = from + to;
+ if (from < blocksize && to > PAGE_CACHE_SIZE - blocksize)
+ return 0;
+
+ head = page_buffers(page);
+ bh = head;
+ block_start = 0;
+ do {
+ block_end = block_start + blocksize;
+ if (block_end > from && block_start < to) {
+ if (!buffer_uptodate(bh)) {
+ ret = 0;
+ break;
+ }
+ if (block_end >= to)
+ break;
+ }
+ block_start = block_end;
+ bh = bh->b_this_page;
+ } while (bh != head);
+
+ return ret;
+}
+EXPORT_SYMBOL(block_is_partially_uptodate);
+
+/*
* Generic "read page" function for block devices that have the normal
* get_block functionality. This is most of the block device filesystems.
* Reads the page asynchronously --- the unlock_buffer() and
@@ -3272,7 +3317,7 @@ int bh_submit_read(struct buffer_head *bh)
EXPORT_SYMBOL(bh_submit_read);
static void
-init_buffer_head(struct kmem_cache *cachep, void *data)
+init_buffer_head(void *data)
{
struct buffer_head *bh = data;
OpenPOWER on IntegriCloud