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author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2021-02-26 04:15:52 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-26 20:40:59 +0300 |
commit | 54fa39ac2e00b1b8c2a7fe72e648773ffa48f76d (patch) | |
tree | 5a694c1659febe9931a4f37600060e47c2087bab /fs | |
parent | 41139aa4c3a31ee7e072fc63353c74035aade2ff (diff) | |
download | linux-54fa39ac2e00b1b8c2a7fe72e648773ffa48f76d.tar.xz |
iomap: use mapping_seek_hole_data
Enhance mapping_seek_hole_data() to handle partially uptodate pages and
convert the iomap seek code to call it.
Link: https://lkml.kernel.org/r/20201112212641.27837-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/iomap/seek.c | 125 |
1 files changed, 11 insertions, 114 deletions
diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c index 107ee80c3568..dab1b02eba5b 100644 --- a/fs/iomap/seek.c +++ b/fs/iomap/seek.c @@ -10,122 +10,17 @@ #include <linux/pagemap.h> #include <linux/pagevec.h> -/* - * Seek for SEEK_DATA / SEEK_HOLE within @page, starting at @lastoff. - * Returns true if found and updates @lastoff to the offset in file. - */ -static bool -page_seek_hole_data(struct inode *inode, struct page *page, loff_t *lastoff, - int whence) -{ - 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 (WARN_ON_ONCE(*lastoff >= poff + PAGE_SIZE)) - return false; - - if (*lastoff < poff) { - /* - * Last offset smaller than the start of the page means we found - * a hole: - */ - if (whence == SEEK_HOLE) - return true; - *lastoff = poff; - } - - /* - * Just check the page unless we can and should check block ranges: - */ - if (bsize == PAGE_SIZE || !ops->is_partially_uptodate) - return PageUptodate(page) == seek_data; - - lock_page(page); - if (unlikely(page->mapping != inode->i_mapping)) - goto out_unlock_not_found; - - for (off = 0; off < PAGE_SIZE; off += bsize) { - if (offset_in_page(*lastoff) >= 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; -} - -/* - * Seek for SEEK_DATA / SEEK_HOLE in the page cache. - * - * Within unwritten extents, the page cache determines which parts are holes - * and which are data: uptodate buffer heads count as data; everything else - * counts as a hole. - * - * Returns the resulting offset on successs, and -ENOENT otherwise. - */ static loff_t -page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length, - int whence) -{ - pgoff_t index = offset >> PAGE_SHIFT; - pgoff_t end = DIV_ROUND_UP(offset + length, PAGE_SIZE); - loff_t lastoff = offset; - struct pagevec pvec; - - if (length <= 0) - return -ENOENT; - - pagevec_init(&pvec); - - do { - unsigned nr_pages, i; - - nr_pages = pagevec_lookup_range(&pvec, inode->i_mapping, &index, - end - 1); - if (nr_pages == 0) - break; - - for (i = 0; i < nr_pages; i++) { - struct page *page = pvec.pages[i]; - - if (page_seek_hole_data(inode, page, &lastoff, whence)) - goto check_range; - lastoff = page_offset(page) + PAGE_SIZE; - } - pagevec_release(&pvec); - } while (index < end); - - /* When no page at lastoff and we are not done, we found a hole. */ - if (whence != SEEK_HOLE) - goto not_found; - -check_range: - if (lastoff < offset + length) - goto out; -not_found: - lastoff = -ENOENT; -out: - pagevec_release(&pvec); - return lastoff; -} - - -static loff_t -iomap_seek_hole_actor(struct inode *inode, loff_t offset, loff_t length, +iomap_seek_hole_actor(struct inode *inode, loff_t start, loff_t length, void *data, struct iomap *iomap, struct iomap *srcmap) { + loff_t offset = start; + switch (iomap->type) { case IOMAP_UNWRITTEN: - offset = page_cache_seek_hole_data(inode, offset, length, - SEEK_HOLE); - if (offset < 0) + offset = mapping_seek_hole_data(inode->i_mapping, start, + start + length, SEEK_HOLE); + if (offset == start + length) return length; fallthrough; case IOMAP_HOLE: @@ -164,15 +59,17 @@ iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops) EXPORT_SYMBOL_GPL(iomap_seek_hole); static loff_t -iomap_seek_data_actor(struct inode *inode, loff_t offset, loff_t length, +iomap_seek_data_actor(struct inode *inode, loff_t start, loff_t length, void *data, struct iomap *iomap, struct iomap *srcmap) { + loff_t offset = start; + switch (iomap->type) { case IOMAP_HOLE: return length; case IOMAP_UNWRITTEN: - offset = page_cache_seek_hole_data(inode, offset, length, - SEEK_DATA); + offset = mapping_seek_hole_data(inode->i_mapping, start, + start + length, SEEK_DATA); if (offset < 0) return length; fallthrough; |