Unverified Commit 1da86618 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Christian Brauner
Browse files

fs: Convert aops->write_begin to take a folio 



Convert all callers from working on a page to working on one page
of a folio (support for working on an entire folio can come later).
Removes a lot of folio->page->folio conversions.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent a225800f

Documentation/filesystems/locking.rst

+2 −2
Original line number Diff line number Diff line
@@ -251,7 +251,7 @@ prototypes:: 
	void (*readahead)(struct readahead_control *);

	int (*write_begin)(struct file *, struct address_space *mapping,

				loff_t pos, unsigned len,

				struct page **pagep, void **fsdata);

				struct folio **foliop, void **fsdata);

	int (*write_end)(struct file *, struct address_space *mapping,

				loff_t pos, unsigned len, unsigned copied,

				struct folio *folio, void *fsdata);
@@ -280,7 +280,7 @@ read_folio: yes, unlocks shared 
writepages:

dirty_folio:		maybe

readahead:		yes, unlocks				shared

write_begin:		locks the page		 exclusive

write_begin:		locks the folio		 exclusive

write_end:		yes, unlocks		 exclusive

bmap:

invalidate_folio:	yes					exclusive

Documentation/filesystems/vfs.rst

+3 −3
Original line number Diff line number Diff line
@@ -926,12 +926,12 @@ cache in your filesystem. The following members are defined: 
	(if they haven't been read already) so that the updated blocks

	can be written out properly.



	The filesystem must return the locked pagecache page for the

	specified offset, in ``*pagep``, for the caller to write into.

	The filesystem must return the locked pagecache folio for the

	specified offset, in ``*foliop``, for the caller to write into.



	It must be able to cope with short writes (where the length

	passed to write_begin is greater than the number of bytes copied

	into the page).

	into the folio).



	A void * may be returned in fsdata, which then gets passed into

	write_end.

block/fops.c

+2 −2
Original line number Diff line number Diff line
@@ -451,9 +451,9 @@ static void blkdev_readahead(struct readahead_control *rac) 
}



static int blkdev_write_begin(struct file *file, struct address_space *mapping,

		loff_t pos, unsigned len, struct page **pagep, void **fsdata)

		loff_t pos, unsigned len, struct folio **foliop, void **fsdata)

{

	return block_write_begin(mapping, pos, len, pagep, blkdev_get_block);

	return block_write_begin(mapping, pos, len, foliop, blkdev_get_block);

}



static int blkdev_write_end(struct file *file, struct address_space *mapping,

drivers/gpu/drm/i915/gem/i915_gem_shmem.c

+22 −25
Original line number Diff line number Diff line
@@ -424,7 +424,8 @@ shmem_pwrite(struct drm_i915_gem_object *obj, 
	struct address_space *mapping = obj->base.filp->f_mapping;

	const struct address_space_operations *aops = mapping->a_ops;

	char __user *user_data = u64_to_user_ptr(arg->data_ptr);

	u64 remain, offset;

	u64 remain;

	loff_t pos;

	unsigned int pg;



	/* Caller already validated user args */
@@ -457,12 +458,12 @@ shmem_pwrite(struct drm_i915_gem_object *obj, 
	 */



	remain = arg->size;

	offset = arg->offset;

	pg = offset_in_page(offset);

	pos = arg->offset;

	pg = offset_in_page(pos);



	do {

		unsigned int len, unwritten;

		struct page *page;

		struct folio *folio;

		void *data, *vaddr;

		int err;

		char __maybe_unused c;
@@ -480,21 +481,19 @@ shmem_pwrite(struct drm_i915_gem_object *obj, 
		if (err)

			return err;



		err = aops->write_begin(obj->base.filp, mapping, offset, len,

					&page, &data);

		err = aops->write_begin(obj->base.filp, mapping, pos, len,

					&folio, &data);

		if (err < 0)

			return err;



		vaddr = kmap_local_page(page);

		vaddr = kmap_local_folio(folio, offset_in_folio(folio, pos));

		pagefault_disable();

		unwritten = __copy_from_user_inatomic(vaddr + pg,

						      user_data,

						      len);

		unwritten = __copy_from_user_inatomic(vaddr, user_data, len);

		pagefault_enable();

		kunmap_local(vaddr);



		err = aops->write_end(obj->base.filp, mapping, offset, len,

				      len - unwritten, page_folio(page), data);

		err = aops->write_end(obj->base.filp, mapping, pos, len,

				      len - unwritten, folio, data);

		if (err < 0)

			return err;
@@ -504,7 +503,7 @@ shmem_pwrite(struct drm_i915_gem_object *obj, 


		remain -= len;

		user_data += len;

		offset += len;

		pos += len;

		pg = 0;

	} while (remain);
@@ -660,7 +659,7 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *i915, 
	struct drm_i915_gem_object *obj;

	struct file *file;

	const struct address_space_operations *aops;

	resource_size_t offset;

	loff_t pos;

	int err;



	GEM_WARN_ON(IS_DGFX(i915));
@@ -672,29 +671,27 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *i915, 


	file = obj->base.filp;

	aops = file->f_mapping->a_ops;

	offset = 0;

	pos = 0;

	do {

		unsigned int len = min_t(typeof(size), size, PAGE_SIZE);

		struct page *page;

		void *pgdata, *vaddr;

		struct folio *folio;

		void *fsdata;



		err = aops->write_begin(file, file->f_mapping, offset, len,

					&page, &pgdata);

		err = aops->write_begin(file, file->f_mapping, pos, len,

					&folio, &fsdata);

		if (err < 0)

			goto fail;



		vaddr = kmap(page);

		memcpy(vaddr, data, len);

		kunmap(page);

		memcpy_to_folio(folio, offset_in_folio(folio, pos), data, len);



		err = aops->write_end(file, file->f_mapping, offset, len, len,

				      page_folio(page), pgdata);

		err = aops->write_end(file, file->f_mapping, pos, len, len,

				      folio, fsdata);

		if (err < 0)

			goto fail;



		size -= len;

		data += len;

		offset += len;

		pos += len;

	} while (size);



	return obj;

fs/adfs/inode.c

+2 −3
Original line number Diff line number Diff line
@@ -55,12 +55,11 @@ static void adfs_write_failed(struct address_space *mapping, loff_t to) 


static int adfs_write_begin(struct file *file, struct address_space *mapping,

			loff_t pos, unsigned len,

			struct page **pagep, void **fsdata)

			struct folio **foliop, void **fsdata)

{

	int ret;



	*pagep = NULL;

	ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,

	ret = cont_write_begin(file, mapping, pos, len, foliop, fsdata,

				adfs_get_block,

				&ADFS_I(mapping->host)->mmu_private);

	if (unlikely(ret))