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-rw-r--r--mm/filemap.c81
1 files changed, 36 insertions, 45 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index 1694623a6289..6f1be573a5e6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -519,7 +519,7 @@ EXPORT_SYMBOL(filemap_write_and_wait);
*
* Write out and wait upon file offsets lstart->lend, inclusive.
*
- * Note that `lend' is inclusive (describes the last byte to be written) so
+ * Note that @lend is inclusive (describes the last byte to be written) so
* that this function can be used to write to the very end-of-file (end = -1).
*/
int filemap_write_and_wait_range(struct address_space *mapping,
@@ -1277,12 +1277,14 @@ EXPORT_SYMBOL(find_lock_entry);
*
* PCG flags modify how the page is returned.
*
- * FGP_ACCESSED: the page will be marked accessed
- * FGP_LOCK: Page is return locked
- * FGP_CREAT: If page is not present then a new page is allocated using
- * @gfp_mask and added to the page cache and the VM's LRU
- * list. The page is returned locked and with an increased
- * refcount. Otherwise, %NULL is returned.
+ * @fgp_flags can be:
+ *
+ * - FGP_ACCESSED: the page will be marked accessed
+ * - FGP_LOCK: Page is return locked
+ * - FGP_CREAT: If page is not present then a new page is allocated using
+ * @gfp_mask and added to the page cache and the VM's LRU
+ * list. The page is returned locked and with an increased
+ * refcount. Otherwise, NULL is returned.
*
* If FGP_LOCK or FGP_CREAT are specified then the function may sleep even
* if the GFP flags specified for FGP_CREAT are atomic.
@@ -2033,7 +2035,6 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
if (iocb->ki_flags & IOCB_DIRECT) {
struct address_space *mapping = file->f_mapping;
struct inode *inode = mapping->host;
- struct iov_iter data = *iter;
loff_t size;
size = i_size_read(inode);
@@ -2044,11 +2045,12 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
file_accessed(file);
- retval = mapping->a_ops->direct_IO(iocb, &data);
+ retval = mapping->a_ops->direct_IO(iocb, iter);
if (retval >= 0) {
iocb->ki_pos += retval;
- iov_iter_advance(iter, retval);
+ count -= retval;
}
+ iov_iter_revert(iter, count - iov_iter_count(iter));
/*
* Btrfs can have a short DIO read if we encounter
@@ -2059,7 +2061,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
* the rest of the read. Buffered reads will not work for
* DAX files, so don't bother trying.
*/
- if (retval < 0 || !iov_iter_count(iter) || iocb->ki_pos >= size ||
+ if (retval < 0 || !count || iocb->ki_pos >= size ||
IS_DAX(inode))
goto out;
}
@@ -2202,12 +2204,12 @@ int filemap_fault(struct vm_fault *vmf)
struct file_ra_state *ra = &file->f_ra;
struct inode *inode = mapping->host;
pgoff_t offset = vmf->pgoff;
+ pgoff_t max_off;
struct page *page;
- loff_t size;
int ret = 0;
- size = round_up(i_size_read(inode), PAGE_SIZE);
- if (offset >= size >> PAGE_SHIFT)
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ if (unlikely(offset >= max_off))
return VM_FAULT_SIGBUS;
/*
@@ -2256,8 +2258,8 @@ retry_find:
* Found the page and have a reference on it.
* We must recheck i_size under page lock.
*/
- size = round_up(i_size_read(inode), PAGE_SIZE);
- if (unlikely(offset >= size >> PAGE_SHIFT)) {
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ if (unlikely(offset >= max_off)) {
unlock_page(page);
put_page(page);
return VM_FAULT_SIGBUS;
@@ -2323,7 +2325,7 @@ void filemap_map_pages(struct vm_fault *vmf,
struct file *file = vmf->vma->vm_file;
struct address_space *mapping = file->f_mapping;
pgoff_t last_pgoff = start_pgoff;
- loff_t size;
+ unsigned long max_idx;
struct page *head, *page;
rcu_read_lock();
@@ -2369,8 +2371,8 @@ repeat:
if (page->mapping != mapping || !PageUptodate(page))
goto unlock;
- size = round_up(i_size_read(mapping->host), PAGE_SIZE);
- if (page->index >= size >> PAGE_SHIFT)
+ max_idx = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE);
+ if (page->index >= max_idx)
goto unlock;
if (file->f_ra.mmap_miss > 0)
@@ -2704,7 +2706,6 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
ssize_t written;
size_t write_len;
pgoff_t end;
- struct iov_iter data;
write_len = iov_iter_count(from);
end = (pos + write_len - 1) >> PAGE_SHIFT;
@@ -2719,22 +2720,19 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
* about to write. We do this *before* the write so that we can return
* without clobbering -EIOCBQUEUED from ->direct_IO().
*/
- if (mapping->nrpages) {
- written = invalidate_inode_pages2_range(mapping,
+ written = invalidate_inode_pages2_range(mapping,
pos >> PAGE_SHIFT, end);
- /*
- * If a page can not be invalidated, return 0 to fall back
- * to buffered write.
- */
- if (written) {
- if (written == -EBUSY)
- return 0;
- goto out;
- }
+ /*
+ * If a page can not be invalidated, return 0 to fall back
+ * to buffered write.
+ */
+ if (written) {
+ if (written == -EBUSY)
+ return 0;
+ goto out;
}
- data = *from;
- written = mapping->a_ops->direct_IO(iocb, &data);
+ written = mapping->a_ops->direct_IO(iocb, from);
/*
* Finally, try again to invalidate clean pages which might have been
@@ -2744,20 +2742,19 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
* so we don't support it 100%. If this invalidation
* fails, tough, the write still worked...
*/
- if (mapping->nrpages) {
- invalidate_inode_pages2_range(mapping,
- pos >> PAGE_SHIFT, end);
- }
+ invalidate_inode_pages2_range(mapping,
+ pos >> PAGE_SHIFT, end);
if (written > 0) {
pos += written;
- iov_iter_advance(from, written);
+ write_len -= written;
if (pos > i_size_read(inode) && !S_ISBLK(inode->i_mode)) {
i_size_write(inode, pos);
mark_inode_dirty(inode);
}
iocb->ki_pos = pos;
}
+ iov_iter_revert(from, write_len - iov_iter_count(from));
out:
return written;
}
@@ -2794,12 +2791,6 @@ ssize_t generic_perform_write(struct file *file,
ssize_t written = 0;
unsigned int flags = 0;
- /*
- * Copies from kernel address space cannot fail (NFSD is a big user).
- */
- if (!iter_is_iovec(i))
- flags |= AOP_FLAG_UNINTERRUPTIBLE;
-
do {
struct page *page;
unsigned long offset; /* Offset into pagecache page */
@@ -3001,7 +2992,7 @@ EXPORT_SYMBOL(generic_file_write_iter);
* @gfp_mask: memory allocation flags (and I/O mode)
*
* The address_space is to try to release any data against the page
- * (presumably at page->private). If the release was successful, return `1'.
+ * (presumably at page->private). If the release was successful, return '1'.
* Otherwise return zero.
*
* This may also be called if PG_fscache is set on a page, indicating that the
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.