Unverified Commit d937c813 authored by Christian Brauner's avatar Christian Brauner
Browse files

Merge patch series "Squashfs: Update code to not use page->index" 

Phillip Lougher <phillip@squashfs.org.uk> says:

In the near future page->index will be removed [1].  Any code which
still uses page->index needs to be updated.

This patch-set contains 4 patches which updates most of the code in
Squashfs.  The exceptions are functions which have been fixed in
recent patches [2] & [3].

[1]: https://lore.kernel.org/all/Zp8fgUSIBGQ1TN0D@casper.infradead.org/
[2]: https://lore.kernel.org/all/20240817101146.2347378-1-lizetao1@huawei.com/
[3]: https://lore.kernel.org/all/20240817101146.2347378-2-lizetao1@huawei.com/

* patchesf from https://lore.kernel.org/r/20240818235847.170468-1-phillip@squashfs.org.uk:
  Squashfs: Rewrite and update squashfs_readahead_fragment() to not use page->index
  Squashfs: Update squashfs_readpage_block() to not use page->index
  Squashfs: Update squashfs_readahead() to not use page->index
  Squashfs: Update page_actor to not use page->index

Link: https://lore.kernel.org/r/20240818235847.170468-1-phillip@squashfs.org.uk


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parents 424f8cb7 fd54fa6e

fs/squashfs/file.c

+57 −27
Original line number Diff line number Diff line
@@ -494,39 +494,73 @@ static int squashfs_read_folio(struct file *file, struct folio *folio) 
}



static int squashfs_readahead_fragment(struct page **page,

	unsigned int pages, unsigned int expected)

	unsigned int pages, unsigned int expected, loff_t start)

{

	struct inode *inode = page[0]->mapping->host;

	struct squashfs_cache_entry *buffer = squashfs_get_fragment(inode->i_sb,

		squashfs_i(inode)->fragment_block,

		squashfs_i(inode)->fragment_size);

	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;

	unsigned int n, mask = (1 << (msblk->block_log - PAGE_SHIFT)) - 1;

	int error = buffer->error;

	int i, bytes, copied;

	struct squashfs_page_actor *actor;

	unsigned int offset;

	void *addr;

	struct page *last_page;



	if (error)

	if (buffer->error)

		goto out;



	expected += squashfs_i(inode)->fragment_offset;

	actor = squashfs_page_actor_init_special(msblk, page, pages,

							expected, start);

	if (!actor)

		goto out;



	for (n = 0; n < pages; n++) {

		unsigned int base = (page[n]->index & mask) << PAGE_SHIFT;

		unsigned int offset = base + squashfs_i(inode)->fragment_offset;

	squashfs_actor_nobuff(actor);

	addr = squashfs_first_page(actor);



		if (expected > offset) {

			unsigned int avail = min_t(unsigned int, expected -

				offset, PAGE_SIZE);

	for (copied = offset = 0; offset < expected; offset += PAGE_SIZE) {

		int avail = min_t(int, expected - offset, PAGE_SIZE);



			squashfs_fill_page(page[n], buffer, offset, avail);

		if (!IS_ERR(addr)) {

			bytes = squashfs_copy_data(addr, buffer, offset +

					squashfs_i(inode)->fragment_offset, avail);



			if (bytes != avail)

				goto failed;

		}



		unlock_page(page[n]);

		put_page(page[n]);

		copied += avail;

		addr = squashfs_next_page(actor);

	}



	last_page = squashfs_page_actor_free(actor);



	if (copied == expected) {

		/* Last page (if present) may have trailing bytes not filled */

		bytes = copied % PAGE_SIZE;

		if (bytes && last_page)

			memzero_page(last_page, bytes, PAGE_SIZE - bytes);



		for (i = 0; i < pages; i++) {

			flush_dcache_page(page[i]);

			SetPageUptodate(page[i]);

		}

	}



	for (i = 0; i < pages; i++) {

		unlock_page(page[i]);

		put_page(page[i]);

	}



	squashfs_cache_put(buffer);

	return 0;



failed:

	squashfs_page_actor_free(actor);



out:

	squashfs_cache_put(buffer);

	return error;

	return 1;

}



static void squashfs_readahead(struct readahead_control *ractl)
@@ -551,7 +585,6 @@ static void squashfs_readahead(struct readahead_control *ractl) 
		return;



	for (;;) {

		pgoff_t index;

		int res, bsize;

		u64 block = 0;

		unsigned int expected;
@@ -570,26 +603,21 @@ static void squashfs_readahead(struct readahead_control *ractl) 
		if (readahead_pos(ractl) >= i_size_read(inode))

			goto skip_pages;



		index = pages[0]->index >> shift;



		if ((pages[nr_pages - 1]->index >> shift) != index)

			goto skip_pages;



		if (index == file_end && squashfs_i(inode)->fragment_block !=

						SQUASHFS_INVALID_BLK) {

		if (start >> msblk->block_log == file_end &&

				squashfs_i(inode)->fragment_block != SQUASHFS_INVALID_BLK) {

			res = squashfs_readahead_fragment(pages, nr_pages,

							  expected);

							  expected, start);

			if (res)

				goto skip_pages;

			continue;

		}



		bsize = read_blocklist(inode, index, &block);

		bsize = read_blocklist(inode, start >> msblk->block_log, &block);

		if (bsize == 0)

			goto skip_pages;



		actor = squashfs_page_actor_init_special(msblk, pages, nr_pages,

							 expected);

							expected, start);

		if (!actor)

			goto skip_pages;
@@ -602,7 +630,7 @@ static void squashfs_readahead(struct readahead_control *ractl) 


			/* Last page (if present) may have trailing bytes not filled */

			bytes = res % PAGE_SIZE;

			if (index == file_end && bytes && last_page)

			if (start >> msblk->block_log == file_end && bytes && last_page)

				memzero_page(last_page, bytes,

					     PAGE_SIZE - bytes);
@@ -616,6 +644,8 @@ static void squashfs_readahead(struct readahead_control *ractl) 
			unlock_page(pages[i]);

			put_page(pages[i]);

		}



		start += readahead_batch_length(ractl);

	}



	kfree(pages);

fs/squashfs/file_direct.c

+9 −8
Original line number Diff line number Diff line
@@ -23,15 +23,15 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize, 
	int expected)



{

	struct folio *folio = page_folio(target_page);

	struct inode *inode = target_page->mapping->host;

	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;



	loff_t file_end = (i_size_read(inode) - 1) >> PAGE_SHIFT;

	int mask = (1 << (msblk->block_log - PAGE_SHIFT)) - 1;

	loff_t start_index = target_page->index & ~mask;

	loff_t start_index = folio->index & ~mask;

	loff_t end_index = start_index | mask;

	int i, n, pages, bytes, res = -ENOMEM;

	struct page **page;

	struct page **page, *last_page;

	struct squashfs_page_actor *actor;

	void *pageaddr;
@@ -46,7 +46,7 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize, 


	/* Try to grab all the pages covered by the Squashfs block */

	for (i = 0, n = start_index; n <= end_index; n++) {

		page[i] = (n == target_page->index) ? target_page :

		page[i] = (n == folio->index) ? target_page :

			grab_cache_page_nowait(target_page->mapping, n);



		if (page[i] == NULL)
@@ -67,14 +67,15 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize, 
	 * Create a "page actor" which will kmap and kunmap the

	 * page cache pages appropriately within the decompressor

	 */

	actor = squashfs_page_actor_init_special(msblk, page, pages, expected);

	actor = squashfs_page_actor_init_special(msblk, page, pages, expected,

						start_index << PAGE_SHIFT);

	if (actor == NULL)

		goto out;



	/* Decompress directly into the page cache buffers */

	res = squashfs_read_data(inode->i_sb, block, bsize, NULL, actor);



	squashfs_page_actor_free(actor);

	last_page = squashfs_page_actor_free(actor);



	if (res < 0)

		goto mark_errored;
@@ -86,8 +87,8 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize, 


	/* Last page (if present) may have trailing bytes not filled */

	bytes = res % PAGE_SIZE;

	if (page[pages - 1]->index == end_index && bytes) {

		pageaddr = kmap_local_page(page[pages - 1]);

	if (end_index == file_end && last_page && bytes) {

		pageaddr = kmap_local_page(last_page);

		memset(pageaddr + bytes, 0, PAGE_SIZE - bytes);

		kunmap_local(pageaddr);

	}

fs/squashfs/page_actor.c

+8 −3
Original line number Diff line number Diff line
@@ -60,6 +60,11 @@ struct squashfs_page_actor *squashfs_page_actor_init(void **buffer, 
}



/* Implementation of page_actor for decompressing directly into page cache. */

static loff_t page_next_index(struct squashfs_page_actor *actor)

{

	return page_folio(actor->page[actor->next_page])->index;

}



static void *handle_next_page(struct squashfs_page_actor *actor)

{

	int max_pages = (actor->length + PAGE_SIZE - 1) >> PAGE_SHIFT;
@@ -68,7 +73,7 @@ static void *handle_next_page(struct squashfs_page_actor *actor) 
		return NULL;



	if ((actor->next_page == actor->pages) ||

			(actor->next_index != actor->page[actor->next_page]->index)) {

			(actor->next_index != page_next_index(actor))) {

		actor->next_index++;

		actor->returned_pages++;

		actor->last_page = NULL;
@@ -103,7 +108,7 @@ static void direct_finish_page(struct squashfs_page_actor *actor) 
}



struct squashfs_page_actor *squashfs_page_actor_init_special(struct squashfs_sb_info *msblk,

	struct page **page, int pages, int length)

	struct page **page, int pages, int length, loff_t start_index)

{

	struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL);
@@ -125,7 +130,7 @@ struct squashfs_page_actor *squashfs_page_actor_init_special(struct squashfs_sb_ 
	actor->pages = pages;

	actor->next_page = 0;

	actor->returned_pages = 0;

	actor->next_index = page[0]->index & ~((1 << (msblk->block_log - PAGE_SHIFT)) - 1);

	actor->next_index = start_index >> PAGE_SHIFT;

	actor->pageaddr = NULL;

	actor->last_page = NULL;

	actor->alloc_buffer = msblk->decompressor->alloc_buffer;

fs/squashfs/page_actor.h

+2 −1
Original line number Diff line number Diff line
@@ -29,7 +29,8 @@ extern struct squashfs_page_actor *squashfs_page_actor_init(void **buffer, 
				int pages, int length);

extern struct squashfs_page_actor *squashfs_page_actor_init_special(

				struct squashfs_sb_info *msblk,

				struct page **page, int pages, int length);

				struct page **page, int pages, int length,

				loff_t start_index);

static inline struct page *squashfs_page_actor_free(struct squashfs_page_actor *actor)

{

	struct page *last_page = actor->last_page;