#include <linux/percpu.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
+#include <linux/capability.h>
#include <linux/blkdev.h>
#include <linux/file.h>
#include <linux/quotaops.h>
{
int ret = 0;
- if (bdev) {
- int err;
-
- ret = filemap_fdatawrite(bdev->bd_inode->i_mapping);
- err = filemap_fdatawait(bdev->bd_inode->i_mapping);
- if (!ret)
- ret = err;
- }
+ if (bdev)
+ ret = filemap_write_and_wait(bdev->bd_inode->i_mapping);
return ret;
}
EXPORT_SYMBOL(sync_blockdev);
* We need to protect against concurrent writers,
* which could cause livelocks in fsync_buffers_list
*/
- down(&mapping->host->i_sem);
+ mutex_lock(&mapping->host->i_mutex);
err = file->f_op->fsync(file, file->f_dentry, datasync);
if (!ret)
ret = err;
- up(&mapping->host->i_sem);
+ mutex_unlock(&mapping->host->i_mutex);
err = filemap_fdatawait(mapping);
if (!ret)
ret = err;
/* Link the buffer to its page */
set_bh_page(bh, page, offset);
- bh->b_end_io = NULL;
+ init_buffer(bh, NULL, NULL);
}
return head;
/*
* some of those buffers may be aliases of filesystem data.
* grow_dev_page() will go BUG() if this happens.
*/
-static inline int
+static int
grow_buffers(struct block_device *bdev, sector_t block, int size)
{
struct page *page;
/*
* Look up the bh in this cpu's LRU. If it's there, move it to the head.
*/
-static inline struct buffer_head *
+static struct buffer_head *
lookup_bh_lru(struct block_device *bdev, sector_t block, int size)
{
struct buffer_head *ret = NULL;
/*
* Called when truncating a buffer on a page completely.
*/
-static inline void discard_buffer(struct buffer_head * bh)
+static void discard_buffer(struct buffer_head * bh)
{
lock_buffer(bh);
clear_buffer_dirty(bh);
* handle that here by just cleaning them.
*/
- block = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
head = page_buffers(page);
bh = head;
* truncates. Uses prepare/commit_write to allow the filesystem to
* deal with the hole.
*/
-int generic_cont_expand(struct inode *inode, loff_t size)
+static int __generic_cont_expand(struct inode *inode, loff_t size,
+ pgoff_t index, unsigned int offset)
{
struct address_space *mapping = inode->i_mapping;
struct page *page;
- unsigned long index, offset, limit;
+ unsigned long limit;
int err;
err = -EFBIG;
if (size > inode->i_sb->s_maxbytes)
goto out;
- offset = (size & (PAGE_CACHE_SIZE-1)); /* Within page */
-
- /* ugh. in prepare/commit_write, if from==to==start of block, we
- ** skip the prepare. make sure we never send an offset for the start
- ** of a block
- */
- if ((offset & (inode->i_sb->s_blocksize - 1)) == 0) {
- offset++;
- }
- index = size >> PAGE_CACHE_SHIFT;
err = -ENOMEM;
page = grab_cache_page(mapping, index);
if (!page)
goto out;
err = mapping->a_ops->prepare_write(NULL, page, offset, offset);
- if (!err) {
- err = mapping->a_ops->commit_write(NULL, page, offset, offset);
+ if (err) {
+ /*
+ * ->prepare_write() may have instantiated a few blocks
+ * outside i_size. Trim these off again.
+ */
+ unlock_page(page);
+ page_cache_release(page);
+ vmtruncate(inode, inode->i_size);
+ goto out;
}
+
+ err = mapping->a_ops->commit_write(NULL, page, offset, offset);
+
unlock_page(page);
page_cache_release(page);
if (err > 0)
return err;
}
+int generic_cont_expand(struct inode *inode, loff_t size)
+{
+ pgoff_t index;
+ unsigned int offset;
+
+ offset = (size & (PAGE_CACHE_SIZE - 1)); /* Within page */
+
+ /* ugh. in prepare/commit_write, if from==to==start of block, we
+ ** skip the prepare. make sure we never send an offset for the start
+ ** of a block
+ */
+ if ((offset & (inode->i_sb->s_blocksize - 1)) == 0) {
+ /* caller must handle this extra byte. */
+ offset++;
+ }
+ index = size >> PAGE_CACHE_SHIFT;
+
+ return __generic_cont_expand(inode, size, index, offset);
+}
+
+int generic_cont_expand_simple(struct inode *inode, loff_t size)
+{
+ loff_t pos = size - 1;
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ unsigned int offset = (pos & (PAGE_CACHE_SIZE - 1)) + 1;
+
+ /* prepare/commit_write can handle even if from==to==start of block. */
+ return __generic_cont_expand(inode, size, index, offset);
+}
+
/*
* For moronic filesystems that do not allow holes in file.
* We may have to extend the file.
__block_commit_write(inode,page,from,to);
/*
* No need to use i_size_read() here, the i_size
- * cannot change under us because we hold i_sem.
+ * cannot change under us because we hold i_mutex.
*/
if (pos > inode->i_size) {
i_size_write(inode, pos);
pgoff_t index = from >> PAGE_CACHE_SHIFT;
unsigned offset = from & (PAGE_CACHE_SIZE-1);
unsigned blocksize;
- pgoff_t iblock;
+ sector_t iblock;
unsigned length, pos;
struct inode *inode = mapping->host;
struct page *page;
return 0;
length = blocksize - length;
- iblock = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ iblock = (sector_t)index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
page = grab_cache_page(mapping, index);
err = -ENOMEM;
return 0;
}
+/*
+ * Migration function for pages with buffers. This function can only be used
+ * if the underlying filesystem guarantees that no other references to "page"
+ * exist.
+ */
+#ifdef CONFIG_MIGRATION
+int buffer_migrate_page(struct page *newpage, struct page *page)
+{
+ struct address_space *mapping = page->mapping;
+ struct buffer_head *bh, *head;
+
+ if (!mapping)
+ return -EAGAIN;
+
+ if (!page_has_buffers(page))
+ return migrate_page(newpage, page);
+
+ head = page_buffers(page);
+
+ if (migrate_page_remove_references(newpage, page, 3))
+ return -EAGAIN;
+
+ bh = head;
+ do {
+ get_bh(bh);
+ lock_buffer(bh);
+ bh = bh->b_this_page;
+
+ } while (bh != head);
+
+ ClearPagePrivate(page);
+ set_page_private(newpage, page_private(page));
+ set_page_private(page, 0);
+ put_page(page);
+ get_page(newpage);
+
+ bh = head;
+ do {
+ set_bh_page(bh, newpage, bh_offset(bh));
+ bh = bh->b_this_page;
+
+ } while (bh != head);
+
+ SetPagePrivate(newpage);
+
+ migrate_page_copy(newpage, page);
+
+ bh = head;
+ do {
+ unlock_buffer(bh);
+ put_bh(bh);
+ bh = bh->b_this_page;
+
+ } while (bh != head);
+
+ return 0;
+}
+EXPORT_SYMBOL(buffer_migrate_page);
+#endif
+
/*
* Buffer-head allocation
*/
EXPORT_SYMBOL(generic_block_bmap);
EXPORT_SYMBOL(generic_commit_write);
EXPORT_SYMBOL(generic_cont_expand);
+EXPORT_SYMBOL(generic_cont_expand_simple);
EXPORT_SYMBOL(init_buffer);
EXPORT_SYMBOL(invalidate_bdev);
EXPORT_SYMBOL(ll_rw_block);