The patch titled
Subject: ntfs: convert ntfs_writepage to use a folio
has been added to the -mm mm-unstable branch. Its filename is
ntfs-convert-ntfs_writepage-to-use-a-folio.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ntfs-convert-ntfs_writepage-to-use-a-folio.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: ntfs: convert ntfs_writepage to use a folio
Date: Mon, 16 Oct 2023 21:11:05 +0100
use folio APIs throughout. Saves many hidden calls to compound_head().
Link: https://lkml.kernel.org/r/20231016201114.1928083-19-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Cc: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Cc: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ntfs/aops.c | 213 ++++++++++++++++++++++-------------------------
1 file changed, 101 insertions(+), 112 deletions(-)
--- a/fs/ntfs/aops.c~ntfs-convert-ntfs_writepage-to-use-a-folio
+++ a/fs/ntfs/aops.c
@@ -501,28 +501,29 @@ err_out:
#ifdef NTFS_RW
/**
- * ntfs_write_block - write a @page to the backing store
- * @page: page cache page to write out
+ * ntfs_write_block - write a @folio to the backing store
+ * @folio: page cache folio to write out
* @wbc: writeback control structure
*
- * This function is for writing pages belonging to non-resident, non-mst
+ * This function is for writing folios belonging to non-resident, non-mst
* protected attributes to their backing store.
*
- * For a page with buffers, map and write the dirty buffers asynchronously
- * under page writeback. For a page without buffers, create buffers for the
- * page, then proceed as above.
- *
- * If a page doesn't have buffers the page dirty state is definitive. If a page
- * does have buffers, the page dirty state is just a hint, and the buffer dirty
- * state is definitive. (A hint which has rules: dirty buffers against a clean
- * page is illegal. Other combinations are legal and need to be handled. In
- * particular a dirty page containing clean buffers for example.)
+ * For a folio with buffers, map and write the dirty buffers asynchronously
+ * under folio writeback. For a folio without buffers, create buffers for the
+ * folio, then proceed as above.
+ *
+ * If a folio doesn't have buffers the folio dirty state is definitive. If
+ * a folio does have buffers, the folio dirty state is just a hint,
+ * and the buffer dirty state is definitive. (A hint which has rules:
+ * dirty buffers against a clean folio is illegal. Other combinations are
+ * legal and need to be handled. In particular a dirty folio containing
+ * clean buffers for example.)
*
* Return 0 on success and -errno on error.
*
* Based on ntfs_read_block() and __block_write_full_folio().
*/
-static int ntfs_write_block(struct page *page, struct writeback_control *wbc)
+static int ntfs_write_block(struct folio *folio, struct writeback_control *wbc)
{
VCN vcn;
LCN lcn;
@@ -540,41 +541,29 @@ static int ntfs_write_block(struct page
bool need_end_writeback;
unsigned char blocksize_bits;
- vi = page->mapping->host;
+ vi = folio->mapping->host;
ni = NTFS_I(vi);
vol = ni->vol;
ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
- "0x%lx.", ni->mft_no, ni->type, page->index);
+ "0x%lx.", ni->mft_no, ni->type, folio->index);
BUG_ON(!NInoNonResident(ni));
BUG_ON(NInoMstProtected(ni));
blocksize = vol->sb->s_blocksize;
blocksize_bits = vol->sb->s_blocksize_bits;
- if (!page_has_buffers(page)) {
- BUG_ON(!PageUptodate(page));
- create_empty_buffers(page, blocksize,
+ head = folio_buffers(folio);
+ if (!head) {
+ BUG_ON(!folio_test_uptodate(folio));
+ head = folio_create_empty_buffers(folio, blocksize,
(1 << BH_Uptodate) | (1 << BH_Dirty));
- if (unlikely(!page_has_buffers(page))) {
- ntfs_warning(vol->sb, "Error allocating page "
- "buffers. Redirtying page so we try "
- "again later.");
- /*
- * Put the page back on mapping->dirty_pages, but leave
- * its buffers' dirty state as-is.
- */
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return 0;
- }
}
- bh = head = page_buffers(page);
- BUG_ON(!bh);
+ bh = head;
/* NOTE: Different naming scheme to ntfs_read_block()! */
- /* The first block in the page. */
- block = (s64)page->index << (PAGE_SHIFT - blocksize_bits);
+ /* The first block in the folio. */
+ block = (s64)folio->index << (PAGE_SHIFT - blocksize_bits);
read_lock_irqsave(&ni->size_lock, flags);
i_size = i_size_read(vi);
@@ -591,14 +580,14 @@ static int ntfs_write_block(struct page
* Be very careful. We have no exclusion from block_dirty_folio
* here, and the (potentially unmapped) buffers may become dirty at
* any time. If a buffer becomes dirty here after we've inspected it
- * then we just miss that fact, and the page stays dirty.
+ * then we just miss that fact, and the folio stays dirty.
*
* Buffers outside i_size may be dirtied by block_dirty_folio;
* handle that here by just cleaning them.
*/
/*
- * Loop through all the buffers in the page, mapping all the dirty
+ * Loop through all the buffers in the folio, mapping all the dirty
* buffers to disk addresses and handling any aliases from the
* underlying block device's mapping.
*/
@@ -610,13 +599,13 @@ static int ntfs_write_block(struct page
if (unlikely(block >= dblock)) {
/*
* Mapped buffers outside i_size will occur, because
- * this page can be outside i_size when there is a
+ * this folio can be outside i_size when there is a
* truncate in progress. The contents of such buffers
* were zeroed by ntfs_writepage().
*
* FIXME: What about the small race window where
* ntfs_writepage() has not done any clearing because
- * the page was within i_size but before we get here,
+ * the folio was within i_size but before we get here,
* vmtruncate() modifies i_size?
*/
clear_buffer_dirty(bh);
@@ -632,38 +621,38 @@ static int ntfs_write_block(struct page
if (unlikely((block >= iblock) &&
(initialized_size < i_size))) {
/*
- * If this page is fully outside initialized
- * size, zero out all pages between the current
- * initialized size and the current page. Just
+ * If this folio is fully outside initialized
+ * size, zero out all folios between the current
+ * initialized size and the current folio. Just
* use ntfs_read_folio() to do the zeroing
* transparently.
*/
if (block > iblock) {
// TODO:
- // For each page do:
- // - read_cache_page()
- // Again for each page do:
- // - wait_on_page_locked()
- // - Check (PageUptodate(page) &&
- // !PageError(page))
+ // For each folio do:
+ // - read_cache_folio()
+ // Again for each folio do:
+ // - wait_on_folio_locked()
+ // - Check (folio_test_uptodate(folio) &&
+ // !folio_test_error(folio))
// Update initialized size in the attribute and
// in the inode.
- // Again, for each page do:
+ // Again, for each folio do:
// block_dirty_folio();
- // put_page()
+ // folio_put()
// We don't need to wait on the writes.
// Update iblock.
}
/*
- * The current page straddles initialized size. Zero
+ * The current folio straddles initialized size. Zero
* all non-uptodate buffers and set them uptodate (and
* dirty?). Note, there aren't any non-uptodate buffers
- * if the page is uptodate.
- * FIXME: For an uptodate page, the buffers may need to
+ * if the folio is uptodate.
+ * FIXME: For an uptodate folio, the buffers may need to
* be written out because they were not initialized on
* disk before.
*/
- if (!PageUptodate(page)) {
+ if (!folio_test_uptodate(folio)) {
// TODO:
// Zero any non-uptodate buffers up to i_size.
// Set them uptodate and dirty.
@@ -721,14 +710,14 @@ lock_retry_remap:
unsigned long *bpos, *bend;
/* Check if the buffer is zero. */
- kaddr = kmap_atomic(page);
- bpos = (unsigned long *)(kaddr + bh_offset(bh));
- bend = (unsigned long *)((u8*)bpos + blocksize);
+ kaddr = kmap_local_folio(folio, bh_offset(bh));
+ bpos = (unsigned long *)kaddr;
+ bend = (unsigned long *)(kaddr + blocksize);
do {
if (unlikely(*bpos))
break;
} while (likely(++bpos < bend));
- kunmap_atomic(kaddr);
+ kunmap_local(kaddr);
if (bpos == bend) {
/*
* Buffer is zero and sparse, no need to write
@@ -768,7 +757,7 @@ lock_retry_remap:
if (err == -ENOENT || lcn == LCN_ENOENT) {
bh->b_blocknr = -1;
clear_buffer_dirty(bh);
- zero_user(page, bh_offset(bh), blocksize);
+ folio_zero_range(folio, bh_offset(bh), blocksize);
set_buffer_uptodate(bh);
err = 0;
continue;
@@ -795,7 +784,7 @@ lock_retry_remap:
bh = head;
/* Just an optimization, so ->read_folio() is not called later. */
- if (unlikely(!PageUptodate(page))) {
+ if (unlikely(!folio_test_uptodate(folio))) {
int uptodate = 1;
do {
if (!buffer_uptodate(bh)) {
@@ -805,7 +794,7 @@ lock_retry_remap:
}
} while ((bh = bh->b_this_page) != head);
if (uptodate)
- SetPageUptodate(page);
+ folio_mark_uptodate(folio);
}
/* Setup all mapped, dirty buffers for async write i/o. */
@@ -820,7 +809,7 @@ lock_retry_remap:
} else if (unlikely(err)) {
/*
* For the error case. The buffer may have been set
- * dirty during attachment to a dirty page.
+ * dirty during attachment to a dirty folio.
*/
if (err != -ENOMEM)
clear_buffer_dirty(bh);
@@ -833,20 +822,20 @@ lock_retry_remap:
err = 0;
else if (err == -ENOMEM) {
ntfs_warning(vol->sb, "Error allocating memory. "
- "Redirtying page so we try again "
+ "Redirtying folio so we try again "
"later.");
/*
- * Put the page back on mapping->dirty_pages, but
+ * Put the folio back on mapping->dirty_pages, but
* leave its buffer's dirty state as-is.
*/
- redirty_page_for_writepage(wbc, page);
+ folio_redirty_for_writepage(wbc, folio);
err = 0;
} else
- SetPageError(page);
+ folio_set_error(folio);
}
- BUG_ON(PageWriteback(page));
- set_page_writeback(page); /* Keeps try_to_free_buffers() away. */
+ BUG_ON(folio_test_writeback(folio));
+ folio_start_writeback(folio); /* Keeps try_to_free_buffers() away. */
/* Submit the prepared buffers for i/o. */
need_end_writeback = true;
@@ -858,11 +847,11 @@ lock_retry_remap:
}
bh = next;
} while (bh != head);
- unlock_page(page);
+ folio_unlock(folio);
- /* If no i/o was started, need to end_page_writeback(). */
+ /* If no i/o was started, need to end writeback here. */
if (unlikely(need_end_writeback))
- end_page_writeback(page);
+ folio_end_writeback(folio);
ntfs_debug("Done.");
return err;
@@ -1331,8 +1320,9 @@ done:
*/
static int ntfs_writepage(struct page *page, struct writeback_control *wbc)
{
+ struct folio *folio = page_folio(page);
loff_t i_size;
- struct inode *vi = page->mapping->host;
+ struct inode *vi = folio->mapping->host;
ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi);
char *addr;
ntfs_attr_search_ctx *ctx = NULL;
@@ -1341,14 +1331,13 @@ static int ntfs_writepage(struct page *p
int err;
retry_writepage:
- BUG_ON(!PageLocked(page));
+ BUG_ON(!folio_test_locked(folio));
i_size = i_size_read(vi);
- /* Is the page fully outside i_size? (truncate in progress) */
- if (unlikely(page->index >= (i_size + PAGE_SIZE - 1) >>
+ /* Is the folio fully outside i_size? (truncate in progress) */
+ if (unlikely(folio->index >= (i_size + PAGE_SIZE - 1) >>
PAGE_SHIFT)) {
- struct folio *folio = page_folio(page);
/*
- * The page may have dirty, unmapped buffers. Make them
+ * The folio may have dirty, unmapped buffers. Make them
* freeable here, so the page does not leak.
*/
block_invalidate_folio(folio, 0, folio_size(folio));
@@ -1367,7 +1356,7 @@ retry_writepage:
if (ni->type != AT_INDEX_ALLOCATION) {
/* If file is encrypted, deny access, just like NT4. */
if (NInoEncrypted(ni)) {
- unlock_page(page);
+ folio_unlock(folio);
BUG_ON(ni->type != AT_DATA);
ntfs_debug("Denying write access to encrypted file.");
return -EACCES;
@@ -1378,14 +1367,14 @@ retry_writepage:
BUG_ON(ni->name_len);
// TODO: Implement and replace this with
// return ntfs_write_compressed_block(page);
- unlock_page(page);
+ folio_unlock(folio);
ntfs_error(vi->i_sb, "Writing to compressed files is "
"not supported yet. Sorry.");
return -EOPNOTSUPP;
}
// TODO: Implement and remove this check.
if (NInoNonResident(ni) && NInoSparse(ni)) {
- unlock_page(page);
+ folio_unlock(folio);
ntfs_error(vi->i_sb, "Writing to sparse files is not "
"supported yet. Sorry.");
return -EOPNOTSUPP;
@@ -1394,34 +1383,34 @@ retry_writepage:
/* NInoNonResident() == NInoIndexAllocPresent() */
if (NInoNonResident(ni)) {
/* We have to zero every time due to mmap-at-end-of-file. */
- if (page->index >= (i_size >> PAGE_SHIFT)) {
- /* The page straddles i_size. */
- unsigned int ofs = i_size & ~PAGE_MASK;
- zero_user_segment(page, ofs, PAGE_SIZE);
+ if (folio->index >= (i_size >> PAGE_SHIFT)) {
+ /* The folio straddles i_size. */
+ unsigned int ofs = i_size & (folio_size(folio) - 1);
+ folio_zero_segment(folio, ofs, folio_size(folio));
}
/* Handle mst protected attributes. */
if (NInoMstProtected(ni))
return ntfs_write_mst_block(page, wbc);
/* Normal, non-resident data stream. */
- return ntfs_write_block(page, wbc);
+ return ntfs_write_block(folio, wbc);
}
/*
* Attribute is resident, implying it is not compressed, encrypted, or
* mst protected. This also means the attribute is smaller than an mft
- * record and hence smaller than a page, so can simply return error on
- * any pages with index above 0. Note the attribute can actually be
+ * record and hence smaller than a folio, so can simply return error on
+ * any folios with index above 0. Note the attribute can actually be
* marked compressed but if it is resident the actual data is not
* compressed so we are ok to ignore the compressed flag here.
*/
- BUG_ON(page_has_buffers(page));
- BUG_ON(!PageUptodate(page));
- if (unlikely(page->index > 0)) {
- ntfs_error(vi->i_sb, "BUG()! page->index (0x%lx) > 0. "
- "Aborting write.", page->index);
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
- unlock_page(page);
- end_page_writeback(page);
+ BUG_ON(folio_buffers(folio));
+ BUG_ON(!folio_test_uptodate(folio));
+ if (unlikely(folio->index > 0)) {
+ ntfs_error(vi->i_sb, "BUG()! folio->index (0x%lx) > 0. "
+ "Aborting write.", folio->index);
+ BUG_ON(folio_test_writeback(folio));
+ folio_start_writeback(folio);
+ folio_unlock(folio);
+ folio_end_writeback(folio);
return -EIO;
}
if (!NInoAttr(ni))
@@ -1454,12 +1443,12 @@ retry_writepage:
if (unlikely(err))
goto err_out;
/*
- * Keep the VM happy. This must be done otherwise the radix-tree tag
- * PAGECACHE_TAG_DIRTY remains set even though the page is clean.
+ * Keep the VM happy. This must be done otherwise
+ * PAGECACHE_TAG_DIRTY remains set even though the folio is clean.
*/
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
- unlock_page(page);
+ BUG_ON(folio_test_writeback(folio));
+ folio_start_writeback(folio);
+ folio_unlock(folio);
attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
i_size = i_size_read(vi);
if (unlikely(attr_len > i_size)) {
@@ -1474,18 +1463,18 @@ retry_writepage:
/* Shrinking cannot fail. */
BUG_ON(err);
}
- addr = kmap_atomic(page);
- /* Copy the data from the page to the mft record. */
+ addr = kmap_local_folio(folio, 0);
+ /* Copy the data from the folio to the mft record. */
memcpy((u8*)ctx->attr +
le16_to_cpu(ctx->attr->data.resident.value_offset),
addr, attr_len);
- /* Zero out of bounds area in the page cache page. */
- memset(addr + attr_len, 0, PAGE_SIZE - attr_len);
- kunmap_atomic(addr);
- flush_dcache_page(page);
+ /* Zero out of bounds area in the page cache folio. */
+ memset(addr + attr_len, 0, folio_size(folio) - attr_len);
+ kunmap_local(addr);
+ flush_dcache_folio(folio);
flush_dcache_mft_record_page(ctx->ntfs_ino);
- /* We are done with the page. */
- end_page_writeback(page);
+ /* We are done with the folio. */
+ folio_end_writeback(folio);
/* Finally, mark the mft record dirty, so it gets written back. */
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
@@ -1496,18 +1485,18 @@ err_out:
ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying "
"page so we try again later.");
/*
- * Put the page back on mapping->dirty_pages, but leave its
+ * Put the folio back on mapping->dirty_pages, but leave its
* buffers' dirty state as-is.
*/
- redirty_page_for_writepage(wbc, page);
+ folio_redirty_for_writepage(wbc, folio);
err = 0;
} else {
ntfs_error(vi->i_sb, "Resident attribute write failed with "
"error %i.", err);
- SetPageError(page);
+ folio_set_error(folio);
NVolSetErrors(ni->vol);
}
- unlock_page(page);
+ folio_unlock(folio);
if (ctx)
ntfs_attr_put_search_ctx(ctx);
if (m)
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-make-lock_folio_maybe_drop_mmap-vma-lock-aware.patch
mm-call-wp_page_copy-under-the-vma-lock.patch
mm-handle-shared-faults-under-the-vma-lock.patch
mm-handle-cow-faults-under-the-vma-lock.patch
mm-handle-read-faults-under-the-vma-lock.patch
mm-handle-write-faults-to-ro-pages-under-the-vma-lock.patch
iomap-hold-state_lock-over-call-to-ifs_set_range_uptodate.patch
iomap-protect-read_bytes_pending-with-the-state_lock.patch
mm-add-folio_end_read.patch
ext4-use-folio_end_read.patch
buffer-use-folio_end_read.patch
iomap-use-folio_end_read.patch
bitops-add-xor_unlock_is_negative_byte.patch
alpha-implement-xor_unlock_is_negative_byte.patch
m68k-implement-xor_unlock_is_negative_byte.patch
mips-implement-xor_unlock_is_negative_byte.patch
powerpc-implement-arch_xor_unlock_is_negative_byte-on-32-bit.patch
riscv-implement-xor_unlock_is_negative_byte.patch
s390-implement-arch_xor_unlock_is_negative_byte.patch
mm-delete-checks-for-xor_unlock_is_negative_byte.patch
mm-add-folio_xor_flags_has_waiters.patch
mm-make-__end_folio_writeback-return-void.patch
mm-use-folio_xor_flags_has_waiters-in-folio_end_writeback.patch
filemap-remove-use-of-wait-bookmarks.patch
sched-remove-wait-bookmarks.patch
buffer-return-bool-from-grow_dev_folio.patch
buffer-make-folio_create_empty_buffers-return-a-buffer_head.patch
mpage-convert-map_buffer_to_folio-to-folio_create_empty_buffers.patch
ext4-convert-to-folio_create_empty_buffers.patch
buffer-add-get_nth_bh.patch
gfs2-convert-inode-unstuffing-to-use-a-folio.patch
gfs2-convert-gfs2_getbuf-to-folios.patch
gfs2-convert-gfs2_getjdatabuf-to-use-a-folio.patch
gfs2-convert-gfs2_write_buf_to_page-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_freeze_buffer-to-use-a-folio.patch
nilfs2-convert-nilfs_grab_buffer-to-use-a-folio.patch
nilfs2-convert-nilfs_copy_page-to-nilfs_copy_folio.patch
nilfs2-convert-nilfs_mdt_forget_block-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_get_frozen_buffer-to-use-a-folio.patch
nilfs2-remove-nilfs_page_get_nth_block.patch
nilfs2-convert-nilfs_lookup_dirty_data_buffers-to-use-folio_create_empty_buffers.patch
ntfs-convert-ntfs_read_block-to-use-a-folio.patch
ntfs-convert-ntfs_writepage-to-use-a-folio.patch
ntfs-convert-ntfs_prepare_pages_for_non_resident_write-to-folios.patch
ntfs3-convert-ntfs_zero_range-to-use-a-folio.patch
ocfs2-convert-ocfs2_map_page_blocks-to-use-a-folio.patch
reiserfs-convert-writepage-to-use-a-folio.patch
ufs-add-ufs_get_locked_folio-and-ufs_put_locked_folio.patch
ufs-use-ufs_get_locked_folio-in-ufs_alloc_lastblock.patch
ufs-convert-ufs_change_blocknr-to-use-folios.patch
ufs-remove-ufs_get_locked_page.patch
buffer-remove-folio_create_empty_buffers.patch
