From bd735bdaa62fb64980c07f5443f24aefd0081569 Mon Sep 17 00:00:00 2001 From: Jeffle Xu Date: Mon, 25 Apr 2022 20:21:41 +0800 Subject: erofs: implement fscache-based data read for inline layout Implement the data plane of reading data from data blobs over fscache for inline layout. For the heading non-inline part, the data plane for non-inline layout is reused, while only the tail packing part needs special handling. Signed-off-by: Jeffle Xu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20220425122143.56815-20-jefflexu@linux.alibaba.com Acked-by: Chao Yu Signed-off-by: Gao Xiang --- fs/erofs/fscache.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'fs') diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index b3af72af7c88..5b779812a5ee 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -83,6 +83,33 @@ out: return ret; } +static int erofs_fscache_readpage_inline(struct folio *folio, + struct erofs_map_blocks *map) +{ + struct super_block *sb = folio_mapping(folio)->host->i_sb; + struct erofs_buf buf = __EROFS_BUF_INITIALIZER; + erofs_blk_t blknr; + size_t offset, len; + void *src, *dst; + + /* For tail packing layout, the offset may be non-zero. */ + offset = erofs_blkoff(map->m_pa); + blknr = erofs_blknr(map->m_pa); + len = map->m_llen; + + src = erofs_read_metabuf(&buf, sb, blknr, EROFS_KMAP); + if (IS_ERR(src)) + return PTR_ERR(src); + + dst = kmap_local_folio(folio, 0); + memcpy(dst, src + offset, len); + memset(dst + len, 0, PAGE_SIZE - len); + kunmap_local(dst); + + erofs_put_metabuf(&buf); + return 0; +} + static int erofs_fscache_readpage(struct file *file, struct page *page) { struct folio *folio = page_folio(page); @@ -108,6 +135,11 @@ static int erofs_fscache_readpage(struct file *file, struct page *page) goto out_uptodate; } + if (map.m_flags & EROFS_MAP_META) { + ret = erofs_fscache_readpage_inline(folio, &map); + goto out_uptodate; + } + mdev = (struct erofs_map_dev) { .m_deviceid = map.m_deviceid, .m_pa = map.m_pa, -- cgit v1.2.3