From: Christoph Hellwig <hch@lst.de>
To: linux-xfs@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
linux-mm@kvack.org
Subject: [PATCH 05/34] fs: use ->is_partially_uptodate in page_cache_seek_hole_data
Date: Fri, 18 May 2018 18:48:01 +0200 [thread overview]
Message-ID: <20180518164830.1552-6-hch@lst.de> (raw)
In-Reply-To: <20180518164830.1552-1-hch@lst.de>
This way the implementation doesn't depend on buffer_head internals.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/iomap.c | 83 +++++++++++++++++++++++++++---------------------------
1 file changed, 42 insertions(+), 41 deletions(-)
diff --git a/fs/iomap.c b/fs/iomap.c
index bef5e91d40bf..0fecd5789d7b 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -594,31 +594,54 @@ EXPORT_SYMBOL_GPL(iomap_fiemap);
*
* Returns the offset within the file on success, and -ENOENT otherwise.
*/
-static loff_t
-page_seek_hole_data(struct page *page, loff_t lastoff, int whence)
+static bool
+page_seek_hole_data(struct inode *inode, struct page *page, loff_t *lastoff,
+ int whence)
{
- loff_t offset = page_offset(page);
- struct buffer_head *bh, *head;
+ const struct address_space_operations *ops = inode->i_mapping->a_ops;
+ unsigned int bsize = i_blocksize(inode), off;
bool seek_data = whence == SEEK_DATA;
+ loff_t poff = page_offset(page);
- if (lastoff < offset)
- lastoff = offset;
-
- bh = head = page_buffers(page);
- do {
- offset += bh->b_size;
- if (lastoff >= offset)
- continue;
+ if (WARN_ON_ONCE(*lastoff >= poff + PAGE_SIZE))
+ return false;
+ if (*lastoff < poff) {
/*
- * Any buffer with valid data in it should have BH_Uptodate set.
+ * Last offset smaller than the start of the page means we found
+ * a hole:
*/
- if (buffer_uptodate(bh) == seek_data)
- return lastoff;
+ if (whence == SEEK_HOLE)
+ return true;
+ *lastoff = poff;
+ }
- lastoff = offset;
- } while ((bh = bh->b_this_page) != head);
- return -ENOENT;
+ /*
+ * Just check the page unless we can and should check block ranges:
+ */
+ if (bsize == PAGE_SIZE || !ops->is_partially_uptodate) {
+ if (PageUptodate(page) == seek_data)
+ return true;
+ return false;
+ }
+
+ lock_page(page);
+ if (unlikely(page->mapping != inode->i_mapping))
+ goto out_unlock_not_found;
+
+ for (off = 0; off < PAGE_SIZE; off += bsize) {
+ if ((*lastoff & ~PAGE_MASK) >= off + bsize)
+ continue;
+ if (ops->is_partially_uptodate(page, off, bsize) == seek_data) {
+ unlock_page(page);
+ return true;
+ }
+ *lastoff = poff + off + bsize;
+ }
+
+out_unlock_not_found:
+ unlock_page(page);
+ return false;
}
/*
@@ -655,30 +678,8 @@ page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length,
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
- /*
- * At this point, the page may be truncated or
- * invalidated (changing page->mapping to NULL), or
- * even swizzled back from swapper_space to tmpfs file
- * mapping. However, page->index will not change
- * because we have a reference on the page.
- *
- * If current page offset is beyond where we've ended,
- * we've found a hole.
- */
- if (whence == SEEK_HOLE &&
- lastoff < page_offset(page))
+ if (page_seek_hole_data(inode, page, &lastoff, whence))
goto check_range;
-
- lock_page(page);
- if (likely(page->mapping == inode->i_mapping) &&
- page_has_buffers(page)) {
- lastoff = page_seek_hole_data(page, lastoff, whence);
- if (lastoff >= 0) {
- unlock_page(page);
- goto check_range;
- }
- }
- unlock_page(page);
lastoff = page_offset(page) + PAGE_SIZE;
}
pagevec_release(&pvec);
--
2.17.0
next prev parent reply other threads:[~2018-05-18 16:48 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-18 16:47 buffered I/O without buffer heads in xfs and iomap v2 Christoph Hellwig
2018-05-18 16:47 ` [PATCH 01/34] block: add a lower-level bio_add_page interface Christoph Hellwig
2018-05-18 16:56 ` Jens Axboe
2018-05-18 16:47 ` [PATCH 02/34] fs: factor out a __generic_write_end helper Christoph Hellwig
2018-05-18 16:47 ` [PATCH 03/34] fs: move page_cache_seek_hole_data to iomap.c Christoph Hellwig
2018-05-18 16:48 ` [PATCH 04/34] fs: remove the buffer_unwritten check in page_seek_hole_data Christoph Hellwig
2018-05-18 16:48 ` Christoph Hellwig [this message]
2018-05-21 19:53 ` [PATCH 05/34] fs: use ->is_partially_uptodate in page_cache_seek_hole_data Darrick J. Wong
2018-05-22 7:56 ` Christoph Hellwig
2018-05-18 16:48 ` [PATCH 06/34] mm: give the 'ret' variable a better name __do_page_cache_readahead Christoph Hellwig
2018-05-18 16:48 ` [PATCH 07/34] mm: return an unsigned int from __do_page_cache_readahead Christoph Hellwig
2018-05-18 16:48 ` [PATCH 08/34] mm: split ->readpages calls to avoid non-contiguous pages lists Christoph Hellwig
2018-05-22 14:52 ` Brian Foster
2018-05-18 16:48 ` [PATCH 09/34] iomap: inline data should be an iomap type, not a flag Christoph Hellwig
2018-05-18 16:48 ` [PATCH 10/34] iomap: fix the comment describing IOMAP_NOWAIT Christoph Hellwig
2018-05-18 16:48 ` [PATCH 11/34] iomap: move IOMAP_F_BOUNDARY to gfs2 Christoph Hellwig
2018-05-18 16:48 ` [PATCH 12/34] iomap: use __bio_add_page in iomap_dio_zero Christoph Hellwig
2018-05-18 16:48 ` [PATCH 13/34] iomap: add a iomap_sector helper Christoph Hellwig
2018-05-18 16:48 ` [PATCH 14/34] iomap: add an iomap-based bmap implementation Christoph Hellwig
2018-05-18 16:48 ` [PATCH 15/34] iomap: add an iomap-based readpage and readpages implementation Christoph Hellwig
2018-05-18 16:48 ` [PATCH 16/34] iomap: add initial support for writes without buffer heads Christoph Hellwig
2018-05-21 23:27 ` Darrick J. Wong
2018-05-22 0:07 ` Dave Chinner
2018-05-22 8:24 ` Christoph Hellwig
2018-05-22 22:38 ` Dave Chinner
2018-05-23 6:03 ` Christoph Hellwig
2018-05-22 8:20 ` Christoph Hellwig
2018-05-22 8:31 ` Christoph Hellwig
2018-05-22 9:39 ` Christoph Hellwig
2018-05-18 16:48 ` [PATCH 17/34] xfs: use iomap_bmap Christoph Hellwig
2018-05-18 16:48 ` [PATCH 18/34] xfs: use iomap for blocksize == PAGE_SIZE readpage and readpages Christoph Hellwig
2018-05-18 16:48 ` [PATCH 19/34] xfs: simplify xfs_bmap_punch_delalloc_range Christoph Hellwig
2018-05-18 16:48 ` [PATCH 20/34] xfs: simplify xfs_aops_discard_page Christoph Hellwig
2018-05-18 16:48 ` [PATCH 21/34] xfs: move locking into xfs_bmap_punch_delalloc_range Christoph Hellwig
2018-05-18 16:48 ` [PATCH 22/34] xfs: make xfs_writepage_map extent map centric Christoph Hellwig
2018-05-18 16:48 ` [PATCH 23/34] xfs: remove the now unused XFS_BMAPI_IGSTATE flag Christoph Hellwig
2018-05-18 16:48 ` [PATCH 24/34] xfs: remove xfs_reflink_find_cow_mapping Christoph Hellwig
2018-05-18 16:48 ` [PATCH 25/34] xfs: remove xfs_reflink_trim_irec_to_next_cow Christoph Hellwig
2018-05-18 16:48 ` [PATCH 26/34] xfs: simplify xfs_map_blocks by using xfs_iext_lookup_extent directly Christoph Hellwig
2018-05-18 16:48 ` [PATCH 27/34] xfs: don't clear imap_valid for a non-uptodate buffers Christoph Hellwig
2018-05-18 16:48 ` [PATCH 28/34] xfs: remove the imap_valid flag Christoph Hellwig
2018-05-18 16:48 ` [PATCH 29/34] xfs: don't look at buffer heads in xfs_add_to_ioend Christoph Hellwig
2018-05-18 16:48 ` [PATCH 30/34] xfs: move all writeback buffer_head manipulation into xfs_map_at_offset Christoph Hellwig
2018-05-18 16:48 ` [PATCH 31/34] xfs: remove xfs_start_page_writeback Christoph Hellwig
2018-05-18 16:48 ` [PATCH 32/34] xfs: refactor the tail of xfs_writepage_map Christoph Hellwig
2018-05-18 16:48 ` [PATCH 33/34] xfs: do not set the page uptodate in xfs_writepage_map Christoph Hellwig
2018-05-18 16:48 ` [PATCH 34/34] xfs: allow writeback on pages without buffer heads Christoph Hellwig
2018-05-21 20:46 ` buffered I/O without buffer heads in xfs and iomap v2 Darrick J. Wong
2018-05-22 20:33 ` Christoph Hellwig
2018-05-23 14:43 buffered I/O without buffer heads in xfs and iomap v3 Christoph Hellwig
2018-05-23 14:43 ` [PATCH 05/34] fs: use ->is_partially_uptodate in page_cache_seek_hole_data Christoph Hellwig
2018-05-30 5:41 ` Darrick J. Wong
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