diff options
Diffstat (limited to 'fs/iomap.c')
| -rw-r--r-- | fs/iomap.c | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/fs/iomap.c b/fs/iomap.c index d14d75a97ab3..ad994c408cb8 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1150,207 +1150,6 @@ out_unlock: EXPORT_SYMBOL_GPL(iomap_page_mkwrite); /* - * 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, - void *data, struct iomap *iomap) -{ - switch (iomap->type) { - case IOMAP_UNWRITTEN: - offset = page_cache_seek_hole_data(inode, offset, length, - SEEK_HOLE); - if (offset < 0) - return length; - /* fall through */ - case IOMAP_HOLE: - *(loff_t *)data = offset; - return 0; - default: - return length; - } -} - -loff_t -iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops) -{ - loff_t size = i_size_read(inode); - loff_t length = size - offset; - loff_t ret; - - /* Nothing to be found before or beyond the end of the file. */ - if (offset < 0 || offset >= size) - return -ENXIO; - - while (length > 0) { - ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops, - &offset, iomap_seek_hole_actor); - if (ret < 0) - return ret; - if (ret == 0) - break; - - offset += ret; - length -= ret; - } - - return offset; -} -EXPORT_SYMBOL_GPL(iomap_seek_hole); - -static loff_t -iomap_seek_data_actor(struct inode *inode, loff_t offset, loff_t length, - void *data, struct iomap *iomap) -{ - switch (iomap->type) { - case IOMAP_HOLE: - return length; - case IOMAP_UNWRITTEN: - offset = page_cache_seek_hole_data(inode, offset, length, - SEEK_DATA); - if (offset < 0) - return length; - /*FALLTHRU*/ - default: - *(loff_t *)data = offset; - return 0; - } -} - -loff_t -iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops) -{ - loff_t size = i_size_read(inode); - loff_t length = size - offset; - loff_t ret; - - /* Nothing to be found before or beyond the end of the file. */ - if (offset < 0 || offset >= size) - return -ENXIO; - - while (length > 0) { - ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops, - &offset, iomap_seek_data_actor); - if (ret < 0) - return ret; - if (ret == 0) - break; - - offset += ret; - length -= ret; - } - - if (length <= 0) - return -ENXIO; - return offset; -} -EXPORT_SYMBOL_GPL(iomap_seek_data); - -/* * Private flags for iomap_dio, must not overlap with the public ones in * iomap.h: */ |