On 2021/7/31 3:46, Gao Xiang wrote:
Since tail-packing inline has been supported by iomap now, let's
convert all EROFS uncompressed data I/O to iomap, which is pretty
straight-forward.
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
---
fs/erofs/data.c | 288 ++++++++----------------------------------------
1 file changed, 49 insertions(+), 239 deletions(-)
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index 911521293b20..6b98156bb5ca 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -9,29 +9,6 @@
#include <linux/dax.h>
#include <trace/events/erofs.h>
-static void erofs_readendio(struct bio *bio)
-{
- struct bio_vec *bvec;
- blk_status_t err = bio->bi_status;
- struct bvec_iter_all iter_all;
-
- bio_for_each_segment_all(bvec, bio, iter_all) {
- struct page *page = bvec->bv_page;
-
- /* page is already locked */
- DBG_BUGON(PageUptodate(page));
-
- if (err)
- SetPageError(page);
- else
- SetPageUptodate(page);
-
- unlock_page(page);
- /* page could be reclaimed now */
- }
- bio_put(bio);
-}
-
struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr)
{
struct address_space *const mapping = sb->s_bdev->bd_inode->i_mapping;
@@ -109,206 +86,6 @@ static int erofs_map_blocks_flatmode(struct inode *inode,
return err;
}
-static inline struct bio *erofs_read_raw_page(struct bio *bio,
- struct address_space *mapping,
- struct page *page,
- erofs_off_t *last_block,
- unsigned int nblocks,
- unsigned int *eblks,
- bool ra)
-{
- struct inode *const inode = mapping->host;
- struct super_block *const sb = inode->i_sb;
- erofs_off_t current_block = (erofs_off_t)page->index;
- int err;
-
- DBG_BUGON(!nblocks);
-
- if (PageUptodate(page)) {
- err = 0;
- goto has_updated;
- }
-
- /* note that for readpage case, bio also equals to NULL */
- if (bio &&
- (*last_block + 1 != current_block || !*eblks)) {
-submit_bio_retry:
- submit_bio(bio);
- bio = NULL;
- }
-
- if (!bio) {
- struct erofs_map_blocks map = {
- .m_la = blknr_to_addr(current_block),
- };
- erofs_blk_t blknr;
- unsigned int blkoff;
-
- err = erofs_map_blocks_flatmode(inode, &map, EROFS_GET_BLOCKS_RAW);
- if (err)
- goto err_out;
-
- /* zero out the holed page */
- if (!(map.m_flags & EROFS_MAP_MAPPED)) {
- zero_user_segment(page, 0, PAGE_SIZE);
- SetPageUptodate(page);
-
- /* imply err = 0, see erofs_map_blocks */
- goto has_updated;
- }
-
- /* for RAW access mode, m_plen must be equal to m_llen */
- DBG_BUGON(map.m_plen != map.m_llen);
-
- blknr = erofs_blknr(map.m_pa);
- blkoff = erofs_blkoff(map.m_pa);
-
- /* deal with inline page */
- if (map.m_flags & EROFS_MAP_META) {
- void *vsrc, *vto;
- struct page *ipage;
-
- DBG_BUGON(map.m_plen > PAGE_SIZE);
-
- ipage = erofs_get_meta_page(inode->i_sb, blknr);
-
- if (IS_ERR(ipage)) {
- err = PTR_ERR(ipage);
- goto err_out;
- }
-
- vsrc = kmap_atomic(ipage);
- vto = kmap_atomic(page);
- memcpy(vto, vsrc + blkoff, map.m_plen);
- memset(vto + map.m_plen, 0, PAGE_SIZE - map.m_plen);
- kunmap_atomic(vto);
- kunmap_atomic(vsrc);
- flush_dcache_page(page);
-
- SetPageUptodate(page);
- /* TODO: could we unlock the page earlier? */
- unlock_page(ipage);
- put_page(ipage);
-
- /* imply err = 0, see erofs_map_blocks */
- goto has_updated;
- }
-
- /* pa must be block-aligned for raw reading */
- DBG_BUGON(erofs_blkoff(map.m_pa));
-
- /* max # of continuous pages */
- if (nblocks > DIV_ROUND_UP(map.m_plen, PAGE_SIZE))
- nblocks = DIV_ROUND_UP(map.m_plen, PAGE_SIZE);
-
- *eblks = bio_max_segs(nblocks);
- bio = bio_alloc(GFP_NOIO, *eblks);
-
- bio->bi_end_io = erofs_readendio;
- bio_set_dev(bio, sb->s_bdev);
- bio->bi_iter.bi_sector = (sector_t)blknr <<
- LOG_SECTORS_PER_BLOCK;
- bio->bi_opf = REQ_OP_READ | (ra ? REQ_RAHEAD : 0);
- }
-
- err = bio_add_page(bio, page, PAGE_SIZE, 0);
- /* out of the extent or bio is full */
- if (err < PAGE_SIZE)
- goto submit_bio_retry;
- --*eblks;
- *last_block = current_block;
- return bio;
-
-err_out:
- /* for sync reading, set page error immediately */
- if (!ra) {
- SetPageError(page);
- ClearPageUptodate(page);
- }
-has_updated:
- unlock_page(page);
-
- /* if updated manually, continuous pages has a gap */
- if (bio)
- submit_bio(bio);
- return err ? ERR_PTR(err) : NULL;
-}
-
-/*
- * since we dont have write or truncate flows, so no inode
- * locking needs to be held at the moment.
- */
-static int erofs_raw_access_readpage(struct file *file, struct page *page)
-{
- erofs_off_t last_block;
- unsigned int eblks;
- struct bio *bio;
-
- trace_erofs_readpage(page, true);
-
- bio = erofs_read_raw_page(NULL, page->mapping,
- page, &last_block, 1, &eblks, false);
-
- if (IS_ERR(bio))
- return PTR_ERR(bio);
-
- if (bio)
- submit_bio(bio);
- return 0;
-}
-
-static void erofs_raw_access_readahead(struct readahead_control *rac)
-{
- erofs_off_t last_block;
- unsigned int eblks;
- struct bio *bio = NULL;
- struct page *page;
-
- trace_erofs_readpages(rac->mapping->host, readahead_index(rac),
- readahead_count(rac), true);
-
- while ((page = readahead_page(rac))) {
- prefetchw(&page->flags);
-
- bio = erofs_read_raw_page(bio, rac->mapping, page, &last_block,
- readahead_count(rac), &eblks, true);
-
- /* all the page errors are ignored when readahead */
- if (IS_ERR(bio)) {
- pr_err("%s, readahead error at page %lu of nid %llu\n",
- __func__, page->index,
- EROFS_I(rac->mapping->host)->nid);
-
- bio = NULL;
- }
-
- put_page(page);
- }
-
- if (bio)
- submit_bio(bio);
-}
-
-static sector_t erofs_bmap(struct address_space *mapping, sector_t block)
-{
- struct inode *inode = mapping->host;
- struct erofs_map_blocks map = {
- .m_la = blknr_to_addr(block),
- };
-
- if (EROFS_I(inode)->datalayout == EROFS_INODE_FLAT_INLINE) {
- erofs_blk_t blks = i_size_read(inode) >> LOG_BLOCK_SIZE;
-
- if (block >> LOG_SECTORS_PER_BLOCK >= blks)
- return 0;
- }
-
- if (!erofs_map_blocks_flatmode(inode, &map, EROFS_GET_BLOCKS_RAW))
- return erofs_blknr(map.m_pa);
-
- return 0;
-}
-
static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned int flags, struct iomap *iomap, struct iomap *srcmap)
{
@@ -327,6 +104,7 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
iomap->offset = map.m_la;
iomap->length = map.m_llen;
iomap->flags = 0;
+ iomap->private = NULL;
if (!(map.m_flags & EROFS_MAP_MAPPED)) {
iomap->type = IOMAP_HOLE;
@@ -336,20 +114,61 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
return 0;
}
- /* that shouldn't happen for now */
if (map.m_flags & EROFS_MAP_META) {
- DBG_BUGON(1);
- return -ENOTBLK;
+ struct page *ipage;
+
+ iomap->type = IOMAP_INLINE;
+ ipage = erofs_get_meta_page(inode->i_sb,
+ erofs_blknr(map.m_pa));
Error handling for erofs_get_meta_page()?
Thanks
+ iomap->inline_data = page_address(ipage) +
+ erofs_blkoff(map.m_pa);
+ iomap->private = ipage;
+ } else {
+ iomap->type = IOMAP_MAPPED;
+ iomap->addr = map.m_pa;
}
- iomap->type = IOMAP_MAPPED;
- iomap->addr = map.m_pa;
return 0;
}
+static int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length,
+ ssize_t written, unsigned flags, struct iomap *iomap)
+{
+ struct page *ipage = iomap->private;
+
+ if (ipage) {
+ DBG_BUGON(iomap->type != IOMAP_INLINE);
+ unlock_page(ipage);
+ put_page(ipage);
+ } else {
+ DBG_BUGON(iomap->type == IOMAP_INLINE);
+ }
+ return written;
+}
+
const struct iomap_ops erofs_iomap_ops = {
.iomap_begin = erofs_iomap_begin,
+ .iomap_end = erofs_iomap_end,
};
+/*
+ * since we dont have write or truncate flows, so no inode
+ * locking needs to be held at the moment.
+ */
+static int erofs_readpage(struct file *file, struct page *page)
+{
+ return iomap_readpage(page, &erofs_iomap_ops);
+}
+
+static void erofs_readahead(struct readahead_control *rac)
+{
+ return iomap_readahead(rac, &erofs_iomap_ops);
+}
+
+static sector_t erofs_bmap(struct address_space *mapping, sector_t block)
+{
+ return iomap_bmap(mapping, block, &erofs_iomap_ops);
+}
+
static int erofs_prepare_dio(struct kiocb *iocb, struct iov_iter *to)
{
struct inode *inode = file_inode(iocb->ki_filp);
@@ -365,15 +184,6 @@ static int erofs_prepare_dio(struct kiocb *iocb, struct iov_iter *to)
if (align & blksize_mask)
return -EINVAL;
-
- /*
- * Temporarily fall back tail-packing inline to buffered I/O instead
- * since tail-packing inline support relies on an iomap core update.
- */
- if (EROFS_I(inode)->datalayout == EROFS_INODE_FLAT_INLINE &&
- iocb->ki_pos + iov_iter_count(to) >
- rounddown(inode->i_size, EROFS_BLKSIZ))
- return 1;
return 0;
}
@@ -409,8 +219,8 @@ static ssize_t erofs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
/* for uncompressed (aligned) files and raw access for other files */
const struct address_space_operations erofs_raw_access_aops = {
- .readpage = erofs_raw_access_readpage,
- .readahead = erofs_raw_access_readahead,
+ .readpage = erofs_readpage,
+ .readahead = erofs_readahead,
.bmap = erofs_bmap,
.direct_IO = noop_direct_IO,
};
