#include <linux/backing-dev.h>
#include <linux/pagevec.h>
#include <linux/blkdev.h>
-#include <linux/backing-dev.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/cpuset.h>
EXPORT_SYMBOL(sync_page_range);
/**
- * sync_page_range_nolock
+ * 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
sync_page_killable, TASK_KILLABLE);
}
-/*
+/**
+ * __lock_page_nosync - get a lock on the page, without calling sync_page()
+ * @page: the page to lock
+ *
* Variant of lock_page that does not require the caller to hold a reference
* on the page's mapping.
*/
return page;
}
-/*
+/**
+ * read_cache_page_async - read into page cache, fill it if needed
+ * @mapping: the page's address_space
+ * @index: the page index
+ * @filler: function to perform the read
+ * @data: destination for read data
+ *
* Same as read_cache_page, but don't wait for page to become unlocked
* after submitting it to the filler.
+ *
+ * Read into the page cache. If a page already exists, and PageUptodate() is
+ * not set, try to fill the page but don't wait for it to become unlocked.
+ *
+ * If the page does not get brought uptodate, return -EIO.
*/
struct page *read_cache_page_async(struct address_space *mapping,
pgoff_t index,
}
EXPORT_SYMBOL(iov_iter_copy_from_user);
-static void __iov_iter_advance_iov(struct iov_iter *i, size_t bytes)
+void iov_iter_advance(struct iov_iter *i, size_t bytes)
{
+ BUG_ON(i->count < bytes);
+
if (likely(i->nr_segs == 1)) {
i->iov_offset += bytes;
+ i->count -= bytes;
} else {
const struct iovec *iov = i->iov;
size_t base = i->iov_offset;
/*
* The !iov->iov_len check ensures we skip over unlikely
- * zero-length segments.
+ * zero-length segments (without overruning the iovec).
*/
- while (bytes || !iov->iov_len) {
- int copy = min(bytes, iov->iov_len - base);
+ while (bytes || unlikely(!iov->iov_len && i->count)) {
+ int copy;
+ copy = min(bytes, iov->iov_len - base);
+ BUG_ON(!i->count || i->count < copy);
+ i->count -= copy;
bytes -= copy;
base += copy;
if (iov->iov_len == base) {
i->iov_offset = base;
}
}
-
-void iov_iter_advance(struct iov_iter *i, size_t bytes)
-{
- BUG_ON(i->count < bytes);
-
- __iov_iter_advance_iov(i, bytes);
- i->count -= bytes;
-}
EXPORT_SYMBOL(iov_iter_advance);
/*