From 9e0b6f31bae6645010d2aa325560e74c05e17e5b Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Sat, 4 Jun 2022 16:24:22 -0400 Subject: buffer: Convert clean_bdev_aliases() to use filemap_get_folios() Use a folio throughout this function. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Acked-by: Christian Brauner (Microsoft) --- fs/buffer.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 898c7f301b1b..276769d3715a 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1604,7 +1604,7 @@ void clean_bdev_aliases(struct block_device *bdev, sector_t block, sector_t len) { struct inode *bd_inode = bdev->bd_inode; struct address_space *bd_mapping = bd_inode->i_mapping; - struct pagevec pvec; + struct folio_batch fbatch; pgoff_t index = block >> (PAGE_SHIFT - bd_inode->i_blkbits); pgoff_t end; int i, count; @@ -1612,24 +1612,24 @@ void clean_bdev_aliases(struct block_device *bdev, sector_t block, sector_t len) struct buffer_head *head; end = (block + len - 1) >> (PAGE_SHIFT - bd_inode->i_blkbits); - pagevec_init(&pvec); - while (pagevec_lookup_range(&pvec, bd_mapping, &index, end)) { - count = pagevec_count(&pvec); + folio_batch_init(&fbatch); + while (filemap_get_folios(bd_mapping, &index, end, &fbatch)) { + count = folio_batch_count(&fbatch); for (i = 0; i < count; i++) { - struct page *page = pvec.pages[i]; + struct folio *folio = fbatch.folios[i]; - if (!page_has_buffers(page)) + if (!folio_buffers(folio)) continue; /* - * We use page lock instead of bd_mapping->private_lock + * We use folio lock instead of bd_mapping->private_lock * to pin buffers here since we can afford to sleep and * it scales better than a global spinlock lock. */ - lock_page(page); - /* Recheck when the page is locked which pins bhs */ - if (!page_has_buffers(page)) + folio_lock(folio); + /* Recheck when the folio is locked which pins bhs */ + head = folio_buffers(folio); + if (!head) goto unlock_page; - head = page_buffers(page); bh = head; do { if (!buffer_mapped(bh) || (bh->b_blocknr < block)) @@ -1643,9 +1643,9 @@ next: bh = bh->b_this_page; } while (bh != head); unlock_page: - unlock_page(page); + folio_unlock(folio); } - pagevec_release(&pvec); + folio_batch_release(&fbatch); cond_resched(); /* End of range already reached? */ if (index > end || !index) -- cgit v1.2.3 From 6e8e79fc84435c159891182cddab8e7784e1b3b2 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 26 May 2022 16:03:43 -0400 Subject: buffer: Remove check for PageError If a buffer is completed with an error, its uptodate flag will be clear, so the page_uptodate variable will have been set to 0. There's no need to check PageError here. Signed-off-by: Matthew Wilcox (Oracle) --- fs/buffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 276769d3715a..a0214e3f90d3 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -282,10 +282,10 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate) spin_unlock_irqrestore(&first->b_uptodate_lock, flags); /* - * If none of the buffers had errors and they are all - * uptodate then we can set the page uptodate. + * If all of the buffers are uptodate then we can set the page + * uptodate. */ - if (page_uptodate && !PageError(page)) + if (page_uptodate) SetPageUptodate(page); unlock_page(page); return; -- cgit v1.2.3 From b7a6eb22ba10f8f6104575dbbbe8c5ad36afd9ac Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 26 May 2022 23:19:49 -0400 Subject: buffer: Don't test folio error in block_read_full_folio() We can cache this information in a local variable instead of communicating from one part of the function to another via folio flags. Signed-off-by: Matthew Wilcox (Oracle) --- fs/buffer.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index a0214e3f90d3..ce9844d7c10f 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2259,6 +2259,7 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) unsigned int blocksize, bbits; int nr, i; int fully_mapped = 1; + bool page_error = false; VM_BUG_ON_FOLIO(folio_test_large(folio), folio); @@ -2283,8 +2284,10 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) if (iblock < lblock) { WARN_ON(bh->b_size != blocksize); err = get_block(inode, iblock, bh, 0); - if (err) + if (err) { folio_set_error(folio); + page_error = true; + } } if (!buffer_mapped(bh)) { folio_zero_range(folio, i * blocksize, @@ -2311,7 +2314,7 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) * All buffers are uptodate - we can set the folio uptodate * as well. But not if get_block() returned an error. */ - if (!folio_test_error(folio)) + if (!page_error) folio_mark_uptodate(folio); folio_unlock(folio); return 0; -- cgit v1.2.3 From cc9cf350d100f4c336edb228cbd078003430cfe7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 13 Jun 2022 07:37:13 +0200 Subject: fs: remove the nobh helpers All callers are gone, so remove the now dead code. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Matthew Wilcox (Oracle) --- fs/buffer.c | 324 ------------------------------------------------------------ 1 file changed, 324 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index ce9844d7c10f..5717d1881d2f 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2537,330 +2537,6 @@ out_unlock: } EXPORT_SYMBOL(block_page_mkwrite); -/* - * nobh_write_begin()'s prereads are special: the buffer_heads are freed - * immediately, while under the page lock. So it needs a special end_io - * handler which does not touch the bh after unlocking it. - */ -static void end_buffer_read_nobh(struct buffer_head *bh, int uptodate) -{ - __end_buffer_read_notouch(bh, uptodate); -} - -/* - * Attach the singly-linked list of buffers created by nobh_write_begin, to - * the page (converting it to circular linked list and taking care of page - * dirty races). - */ -static void attach_nobh_buffers(struct page *page, struct buffer_head *head) -{ - struct buffer_head *bh; - - BUG_ON(!PageLocked(page)); - - spin_lock(&page->mapping->private_lock); - bh = head; - do { - if (PageDirty(page)) - set_buffer_dirty(bh); - if (!bh->b_this_page) - bh->b_this_page = head; - bh = bh->b_this_page; - } while (bh != head); - attach_page_private(page, head); - spin_unlock(&page->mapping->private_lock); -} - -/* - * On entry, the page is fully not uptodate. - * On exit the page is fully uptodate in the areas outside (from,to) - * The filesystem needs to handle block truncation upon failure. - */ -int nobh_write_begin(struct address_space *mapping, loff_t pos, unsigned len, - struct page **pagep, void **fsdata, - get_block_t *get_block) -{ - struct inode *inode = mapping->host; - const unsigned blkbits = inode->i_blkbits; - const unsigned blocksize = 1 << blkbits; - struct buffer_head *head, *bh; - struct page *page; - pgoff_t index; - unsigned from, to; - unsigned block_in_page; - unsigned block_start, block_end; - sector_t block_in_file; - int nr_reads = 0; - int ret = 0; - int is_mapped_to_disk = 1; - - index = pos >> PAGE_SHIFT; - from = pos & (PAGE_SIZE - 1); - to = from + len; - - page = grab_cache_page_write_begin(mapping, index); - if (!page) - return -ENOMEM; - *pagep = page; - *fsdata = NULL; - - if (page_has_buffers(page)) { - ret = __block_write_begin(page, pos, len, get_block); - if (unlikely(ret)) - goto out_release; - return ret; - } - - if (PageMappedToDisk(page)) - return 0; - - /* - * Allocate buffers so that we can keep track of state, and potentially - * attach them to the page if an error occurs. In the common case of - * no error, they will just be freed again without ever being attached - * to the page (which is all OK, because we're under the page lock). - * - * Be careful: the buffer linked list is a NULL terminated one, rather - * than the circular one we're used to. - */ - head = alloc_page_buffers(page, blocksize, false); - if (!head) { - ret = -ENOMEM; - goto out_release; - } - - block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits); - - /* - * We loop across all blocks in the page, whether or not they are - * part of the affected region. This is so we can discover if the - * page is fully mapped-to-disk. - */ - for (block_start = 0, block_in_page = 0, bh = head; - block_start < PAGE_SIZE; - block_in_page++, block_start += blocksize, bh = bh->b_this_page) { - int create; - - block_end = block_start + blocksize; - bh->b_state = 0; - create = 1; - if (block_start >= to) - create = 0; - ret = get_block(inode, block_in_file + block_in_page, - bh, create); - if (ret) - goto failed; - if (!buffer_mapped(bh)) - is_mapped_to_disk = 0; - if (buffer_new(bh)) - clean_bdev_bh_alias(bh); - if (PageUptodate(page)) { - set_buffer_uptodate(bh); - continue; - } - if (buffer_new(bh) || !buffer_mapped(bh)) { - zero_user_segments(page, block_start, from, - to, block_end); - continue; - } - if (buffer_uptodate(bh)) - continue; /* reiserfs does this */ - if (block_start < from || block_end > to) { - lock_buffer(bh); - bh->b_end_io = end_buffer_read_nobh; - submit_bh(REQ_OP_READ, 0, bh); - nr_reads++; - } - } - - if (nr_reads) { - /* - * The page is locked, so these buffers are protected from - * any VM or truncate activity. Hence we don't need to care - * for the buffer_head refcounts. - */ - for (bh = head; bh; bh = bh->b_this_page) { - wait_on_buffer(bh); - if (!buffer_uptodate(bh)) - ret = -EIO; - } - if (ret) - goto failed; - } - - if (is_mapped_to_disk) - SetPageMappedToDisk(page); - - *fsdata = head; /* to be released by nobh_write_end */ - - return 0; - -failed: - BUG_ON(!ret); - /* - * Error recovery is a bit difficult. We need to zero out blocks that - * were newly allocated, and dirty them to ensure they get written out. - * Buffers need to be attached to the page at this point, otherwise - * the handling of potential IO errors during writeout would be hard - * (could try doing synchronous writeout, but what if that fails too?) - */ - attach_nobh_buffers(page, head); - page_zero_new_buffers(page, from, to); - -out_release: - unlock_page(page); - put_page(page); - *pagep = NULL; - - return ret; -} -EXPORT_SYMBOL(nobh_write_begin); - -int nobh_write_end(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) -{ - struct inode *inode = page->mapping->host; - struct buffer_head *head = fsdata; - struct buffer_head *bh; - BUG_ON(fsdata != NULL && page_has_buffers(page)); - - if (unlikely(copied < len) && head) - attach_nobh_buffers(page, head); - if (page_has_buffers(page)) - return generic_write_end(file, mapping, pos, len, - copied, page, fsdata); - - SetPageUptodate(page); - set_page_dirty(page); - if (pos+copied > inode->i_size) { - i_size_write(inode, pos+copied); - mark_inode_dirty(inode); - } - - unlock_page(page); - put_page(page); - - while (head) { - bh = head; - head = head->b_this_page; - free_buffer_head(bh); - } - - return copied; -} -EXPORT_SYMBOL(nobh_write_end); - -/* - * nobh_writepage() - based on block_full_write_page() except - * that it tries to operate without attaching bufferheads to - * the page. - */ -int nobh_writepage(struct page *page, get_block_t *get_block, - struct writeback_control *wbc) -{ - struct inode * const inode = page->mapping->host; - loff_t i_size = i_size_read(inode); - const pgoff_t end_index = i_size >> PAGE_SHIFT; - unsigned offset; - int ret; - - /* Is the page fully inside i_size? */ - if (page->index < end_index) - goto out; - - /* Is the page fully outside i_size? (truncate in progress) */ - offset = i_size & (PAGE_SIZE-1); - if (page->index >= end_index+1 || !offset) { - unlock_page(page); - return 0; /* don't care */ - } - - /* - * The page straddles i_size. It must be zeroed out on each and every - * writepage invocation because it may be mmapped. "A file is mapped - * in multiples of the page size. For a file that is not a multiple of - * the page size, the remaining memory is zeroed when mapped, and - * writes to that region are not written out to the file." - */ - zero_user_segment(page, offset, PAGE_SIZE); -out: - ret = mpage_writepage(page, get_block, wbc); - if (ret == -EAGAIN) - ret = __block_write_full_page(inode, page, get_block, wbc, - end_buffer_async_write); - return ret; -} -EXPORT_SYMBOL(nobh_writepage); - -int nobh_truncate_page(struct address_space *mapping, - loff_t from, get_block_t *get_block) -{ - pgoff_t index = from >> PAGE_SHIFT; - struct inode *inode = mapping->host; - unsigned blocksize = i_blocksize(inode); - struct folio *folio; - struct buffer_head map_bh; - size_t offset; - sector_t iblock; - int err; - - /* Block boundary? Nothing to do */ - if (!(from & (blocksize - 1))) - return 0; - - folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_CREAT, - mapping_gfp_mask(mapping)); - err = -ENOMEM; - if (!folio) - goto out; - - if (folio_buffers(folio)) - goto has_buffers; - - iblock = from >> inode->i_blkbits; - map_bh.b_size = blocksize; - map_bh.b_state = 0; - err = get_block(inode, iblock, &map_bh, 0); - if (err) - goto unlock; - /* unmapped? It's a hole - nothing to do */ - if (!buffer_mapped(&map_bh)) - goto unlock; - - /* Ok, it's mapped. Make sure it's up-to-date */ - if (!folio_test_uptodate(folio)) { - err = mapping->a_ops->read_folio(NULL, folio); - if (err) { - folio_put(folio); - goto out; - } - folio_lock(folio); - if (!folio_test_uptodate(folio)) { - err = -EIO; - goto unlock; - } - if (folio_buffers(folio)) - goto has_buffers; - } - offset = offset_in_folio(folio, from); - folio_zero_segment(folio, offset, round_up(offset, blocksize)); - folio_mark_dirty(folio); - err = 0; - -unlock: - folio_unlock(folio); - folio_put(folio); -out: - return err; - -has_buffers: - folio_unlock(folio); - folio_put(folio); - return block_truncate_page(mapping, from, get_block); -} -EXPORT_SYMBOL(nobh_truncate_page); - int block_truncate_page(struct address_space *mapping, loff_t from, get_block_t *get_block) { -- cgit v1.2.3