diff options
| -rw-r--r-- | fs/erofs/data.c | 98 | ||||
| -rw-r--r-- | fs/erofs/internal.h | 13 |
2 files changed, 90 insertions, 21 deletions
diff --git a/fs/erofs/data.c b/fs/erofs/data.c index 4f98c76ec043..bd37f53f60cb 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -22,6 +22,57 @@ struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr) return page; } +void erofs_unmap_metabuf(struct erofs_buf *buf) +{ + if (buf->kmap_type == EROFS_KMAP) + kunmap(buf->page); + else if (buf->kmap_type == EROFS_KMAP_ATOMIC) + kunmap_atomic(buf->base); + buf->base = NULL; + buf->kmap_type = EROFS_NO_KMAP; +} + +void erofs_put_metabuf(struct erofs_buf *buf) +{ + if (!buf->page) + return; + erofs_unmap_metabuf(buf); + put_page(buf->page); + buf->page = NULL; +} + +void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb, + erofs_blk_t blkaddr, enum erofs_kmap_type type) +{ + struct address_space *const mapping = sb->s_bdev->bd_inode->i_mapping; + erofs_off_t offset = blknr_to_addr(blkaddr); + pgoff_t index = offset >> PAGE_SHIFT; + struct page *page = buf->page; + + if (!page || page->index != index) { + erofs_put_metabuf(buf); + page = read_cache_page_gfp(mapping, index, + mapping_gfp_constraint(mapping, ~__GFP_FS)); + if (IS_ERR(page)) + return page; + /* should already be PageUptodate, no need to lock page */ + buf->page = page; + } + if (buf->kmap_type == EROFS_NO_KMAP) { + if (type == EROFS_KMAP) + buf->base = kmap(page); + else if (type == EROFS_KMAP_ATOMIC) + buf->base = kmap_atomic(page); + buf->kmap_type = type; + } else if (buf->kmap_type != type) { + DBG_BUGON(1); + return ERR_PTR(-EFAULT); + } + if (type == EROFS_NO_KMAP) + return NULL; + return buf->base + (offset & ~PAGE_MASK); +} + static int erofs_map_blocks_flatmode(struct inode *inode, struct erofs_map_blocks *map, int flags) @@ -31,7 +82,7 @@ static int erofs_map_blocks_flatmode(struct inode *inode, struct erofs_inode *vi = EROFS_I(inode); bool tailendpacking = (vi->datalayout == EROFS_INODE_FLAT_INLINE); - nblocks = DIV_ROUND_UP(inode->i_size, PAGE_SIZE); + nblocks = DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); lastblk = nblocks - tailendpacking; /* there is no hole in flatmode */ @@ -72,10 +123,11 @@ static int erofs_map_blocks(struct inode *inode, struct super_block *sb = inode->i_sb; struct erofs_inode *vi = EROFS_I(inode); struct erofs_inode_chunk_index *idx; - struct page *page; + struct erofs_buf buf = __EROFS_BUF_INITIALIZER; u64 chunknr; unsigned int unit; erofs_off_t pos; + void *kaddr; int err = 0; trace_erofs_map_blocks_enter(inode, map, flags); @@ -101,9 +153,9 @@ static int erofs_map_blocks(struct inode *inode, pos = ALIGN(iloc(EROFS_SB(sb), vi->nid) + vi->inode_isize + vi->xattr_isize, unit) + unit * chunknr; - page = erofs_get_meta_page(inode->i_sb, erofs_blknr(pos)); - if (IS_ERR(page)) { - err = PTR_ERR(page); + kaddr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos), EROFS_KMAP); + if (IS_ERR(kaddr)) { + err = PTR_ERR(kaddr); goto out; } map->m_la = chunknr << vi->chunkbits; @@ -112,7 +164,7 @@ static int erofs_map_blocks(struct inode *inode, /* handle block map */ if (!(vi->chunkformat & EROFS_CHUNK_FORMAT_INDEXES)) { - __le32 *blkaddr = page_address(page) + erofs_blkoff(pos); + __le32 *blkaddr = kaddr + erofs_blkoff(pos); if (le32_to_cpu(*blkaddr) == EROFS_NULL_ADDR) { map->m_flags = 0; @@ -123,7 +175,7 @@ static int erofs_map_blocks(struct inode *inode, goto out_unlock; } /* parse chunk indexes */ - idx = page_address(page) + erofs_blkoff(pos); + idx = kaddr + erofs_blkoff(pos); switch (le32_to_cpu(idx->blkaddr)) { case EROFS_NULL_ADDR: map->m_flags = 0; @@ -136,8 +188,7 @@ static int erofs_map_blocks(struct inode *inode, break; } out_unlock: - unlock_page(page); - put_page(page); + erofs_put_metabuf(&buf); out: if (!err) map->m_llen = map->m_plen; @@ -226,16 +277,16 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, } if (map.m_flags & EROFS_MAP_META) { - struct page *ipage; + void *ptr; + struct erofs_buf buf = __EROFS_BUF_INITIALIZER; iomap->type = IOMAP_INLINE; - ipage = erofs_get_meta_page(inode->i_sb, - erofs_blknr(mdev.m_pa)); - if (IS_ERR(ipage)) - return PTR_ERR(ipage); - iomap->inline_data = page_address(ipage) + - erofs_blkoff(mdev.m_pa); - iomap->private = ipage; + ptr = erofs_read_metabuf(&buf, inode->i_sb, + erofs_blknr(mdev.m_pa), EROFS_KMAP); + if (IS_ERR(ptr)) + return PTR_ERR(ptr); + iomap->inline_data = ptr + erofs_blkoff(mdev.m_pa); + iomap->private = buf.base; } else { iomap->type = IOMAP_MAPPED; iomap->addr = mdev.m_pa; @@ -246,12 +297,17 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, static int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length, ssize_t written, unsigned int flags, struct iomap *iomap) { - struct page *ipage = iomap->private; + void *ptr = iomap->private; + + if (ptr) { + struct erofs_buf buf = { + .page = kmap_to_page(ptr), + .base = ptr, + .kmap_type = EROFS_KMAP, + }; - if (ipage) { DBG_BUGON(iomap->type != IOMAP_INLINE); - unlock_page(ipage); - put_page(ipage); + erofs_put_metabuf(&buf); } else { DBG_BUGON(iomap->type == IOMAP_INLINE); } diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index fca3747d97be..7053f1c4171d 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -251,6 +251,19 @@ static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) #error erofs cannot be used in this platform #endif +enum erofs_kmap_type { + EROFS_NO_KMAP, /* don't map the buffer */ + EROFS_KMAP, /* use kmap() to map the buffer */ + EROFS_KMAP_ATOMIC, /* use kmap_atomic() to map the buffer */ +}; + +struct erofs_buf { + struct page *page; + void *base; + enum erofs_kmap_type kmap_type; +}; +#define __EROFS_BUF_INITIALIZER ((struct erofs_buf){ .page = NULL }) + #define ROOT_NID(sb) ((sb)->root_nid) #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) |