/*
* Lock ordering:
*
- * ->i_mmap_lock (vmtruncate)
+ * ->i_mmap_lock (truncate_pagecache)
* ->private_lock (__free_pte->__set_page_dirty_buffers)
* ->swap_lock (exclusive_swap_page, others)
* ->mapping->tree_lock
*
* ->task->proc_lock
* ->dcache_lock (proc_pid_lookup)
+ *
+ * (code doesn't rely on that order, so you could switch it around)
+ * ->tasklist_lock (memory_failure, collect_procs_ao)
+ * ->i_mmap_lock
*/
/*
page->mapping = NULL;
mapping->nrpages--;
__dec_zone_page_state(page, NR_FILE_PAGES);
+ if (PageSwapBacked(page))
+ __dec_zone_page_state(page, NR_SHMEM);
BUG_ON(page_mapped(page));
/*
EXPORT_SYMBOL(filemap_flush);
/**
- * wait_on_page_writeback_range - wait for writeback to complete
- * @mapping: target address_space
- * @start: beginning page index
- * @end: ending page index
+ * filemap_fdatawait_range - wait for writeback to complete
+ * @mapping: address space structure to wait for
+ * @start_byte: offset in bytes where the range starts
+ * @end_byte: offset in bytes where the range ends (inclusive)
*
- * Wait for writeback to complete against pages indexed by start->end
- * inclusive
+ * Walk the list of under-writeback pages of the given address space
+ * in the given range and wait for all of them.
*/
-int wait_on_page_writeback_range(struct address_space *mapping,
- pgoff_t start, pgoff_t end)
+int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte,
+ loff_t end_byte)
{
+ pgoff_t index = start_byte >> PAGE_CACHE_SHIFT;
+ pgoff_t end = end_byte >> PAGE_CACHE_SHIFT;
struct pagevec pvec;
int nr_pages;
int ret = 0;
- pgoff_t index;
- if (end < start)
+ if (end_byte < start_byte)
return 0;
pagevec_init(&pvec, 0);
- index = start;
while ((index <= end) &&
(nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
PAGECACHE_TAG_WRITEBACK,
return ret;
}
-
-/**
- * filemap_fdatawait_range - wait for all under-writeback pages to complete in a given range
- * @mapping: address space structure to wait for
- * @start: offset in bytes where the range starts
- * @end: offset in bytes where the range ends (inclusive)
- *
- * Walk the list of under-writeback pages of the given address space
- * in the given range and wait for all of them.
- *
- * This is just a simple wrapper so that callers don't have to convert offsets
- * to page indexes themselves
- */
-int filemap_fdatawait_range(struct address_space *mapping, loff_t start,
- loff_t end)
-{
- return wait_on_page_writeback_range(mapping, start >> PAGE_CACHE_SHIFT,
- end >> PAGE_CACHE_SHIFT);
-}
EXPORT_SYMBOL(filemap_fdatawait_range);
/**
- * sync_page_range - write and wait on all pages in the passed range
- * @inode: target inode
- * @mapping: target address_space
- * @pos: beginning offset in pages to write
- * @count: number of bytes to write
- *
- * Write and wait upon all the pages in the passed range. This is a "data
- * integrity" operation. It waits upon in-flight writeout before starting and
- * waiting upon new writeout. If there was an IO error, return it.
- *
- * We need to re-take i_mutex during the generic_osync_inode list walk because
- * it is otherwise livelockable.
- */
-int sync_page_range(struct inode *inode, struct address_space *mapping,
- loff_t pos, loff_t count)
-{
- pgoff_t start = pos >> PAGE_CACHE_SHIFT;
- pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
- int ret;
-
- if (!mapping_cap_writeback_dirty(mapping) || !count)
- return 0;
- ret = filemap_fdatawrite_range(mapping, pos, pos + count - 1);
- if (ret == 0) {
- mutex_lock(&inode->i_mutex);
- ret = generic_osync_inode(inode, mapping, OSYNC_METADATA);
- mutex_unlock(&inode->i_mutex);
- }
- if (ret == 0)
- ret = wait_on_page_writeback_range(mapping, start, end);
- return ret;
-}
-EXPORT_SYMBOL(sync_page_range);
-
-/**
- * sync_page_range_nolock - write & wait on all pages in the passed range without locking
- * @inode: target inode
- * @mapping: target address_space
- * @pos: beginning offset in pages to write
- * @count: number of bytes to write
- *
- * Note: Holding i_mutex across sync_page_range_nolock() is not a good idea
- * as it forces O_SYNC writers to different parts of the same file
- * to be serialised right until io completion.
- */
-int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
- loff_t pos, loff_t count)
-{
- pgoff_t start = pos >> PAGE_CACHE_SHIFT;
- pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
- int ret;
-
- if (!mapping_cap_writeback_dirty(mapping) || !count)
- return 0;
- ret = filemap_fdatawrite_range(mapping, pos, pos + count - 1);
- if (ret == 0)
- ret = generic_osync_inode(inode, mapping, OSYNC_METADATA);
- if (ret == 0)
- ret = wait_on_page_writeback_range(mapping, start, end);
- return ret;
-}
-EXPORT_SYMBOL(sync_page_range_nolock);
-
-/**
* filemap_fdatawait - wait for all under-writeback pages to complete
* @mapping: address space structure to wait for
*
if (i_size == 0)
return 0;
- return wait_on_page_writeback_range(mapping, 0,
- (i_size - 1) >> PAGE_CACHE_SHIFT);
+ return filemap_fdatawait_range(mapping, 0, i_size - 1);
}
EXPORT_SYMBOL(filemap_fdatawait);
WB_SYNC_ALL);
/* See comment of filemap_write_and_wait() */
if (err != -EIO) {
- int err2 = wait_on_page_writeback_range(mapping,
- lstart >> PAGE_CACHE_SHIFT,
- lend >> PAGE_CACHE_SHIFT);
+ int err2 = filemap_fdatawait_range(mapping,
+ lstart, lend);
if (!err)
err = err2;
}
if (likely(!error)) {
mapping->nrpages++;
__inc_zone_page_state(page, NR_FILE_PAGES);
+ if (PageSwapBacked(page))
+ __inc_zone_page_state(page, NR_SHMEM);
spin_unlock_irq(&mapping->tree_lock);
} else {
page->mapping = NULL;
}
EXPORT_SYMBOL(filemap_fault);
-struct vm_operations_struct generic_file_vm_ops = {
+const struct vm_operations_struct generic_file_vm_ops = {
.fault = filemap_fault,
};
/*
* Copy as much as we can into the page and return the number of bytes which
- * were sucessfully copied. If a fault is encountered then return the number of
+ * were successfully copied. If a fault is encountered then return the number of
* bytes which were copied.
*/
size_t iov_iter_copy_from_user_atomic(struct page *page,
size_t count, ssize_t written)
{
struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
ssize_t status;
struct iov_iter i;
*ppos = pos + status;
}
- /*
- * If we get here for O_DIRECT writes then we must have fallen through
- * to buffered writes (block instantiation inside i_size). So we sync
- * the file data here, to try to honour O_DIRECT expectations.
- */
- if (unlikely(file->f_flags & O_DIRECT) && written)
- status = filemap_write_and_wait_range(mapping,
- pos, pos + written - 1);
-
return written ? written : status;
}
EXPORT_SYMBOL(generic_file_buffered_write);
* semantics.
*/
endbyte = pos + written_buffered - written - 1;
- err = do_sync_mapping_range(file->f_mapping, pos, endbyte,
- SYNC_FILE_RANGE_WAIT_BEFORE|
- SYNC_FILE_RANGE_WRITE|
- SYNC_FILE_RANGE_WAIT_AFTER);
+ err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte);
if (err == 0) {
written = written_buffered;
invalidate_mapping_pages(mapping,