1)Moved on-disk structures to erofs_fs.h 2)Some naming changes. I think we can keep 'IS_HOLE()' macro, otherwise the code does not look clean(if used directly/without macro).Its getting used only in inode.c so it can be kept there. what do you think ?
Signed-off-by: Pratik Shinde <[email protected]> --- include/erofs/internal.h | 9 ++- include/erofs_fs.h | 11 ++++ lib/inode.c | 153 ++++++++++++++++++++++++++++++++++++++++------- 3 files changed, 150 insertions(+), 23 deletions(-) diff --git a/include/erofs/internal.h b/include/erofs/internal.h index e13adda..2d7466b 100644 --- a/include/erofs/internal.h +++ b/include/erofs/internal.h @@ -63,7 +63,7 @@ struct erofs_sb_info { extern struct erofs_sb_info sbi; struct erofs_inode { - struct list_head i_hash, i_subdirs, i_xattrs; + struct list_head i_hash, i_subdirs, i_xattrs, i_sparse_extents; unsigned int i_count; struct erofs_inode *i_parent; @@ -93,6 +93,7 @@ struct erofs_inode { unsigned int xattr_isize; unsigned int extent_isize; + unsigned int sparse_extent_isize; erofs_nid_t nid; struct erofs_buffer_head *bh; @@ -139,5 +140,11 @@ static inline const char *erofs_strerror(int err) return msg; } +struct erofs_sparse_extent_node { + struct list_head next; + erofs_blk_t lblk; + erofs_blk_t pblk; + u32 len; +}; #endif diff --git a/include/erofs_fs.h b/include/erofs_fs.h index bcc4f0c..a63e1c6 100644 --- a/include/erofs_fs.h +++ b/include/erofs_fs.h @@ -321,5 +321,16 @@ static inline void erofs_check_ondisk_layout_definitions(void) Z_EROFS_VLE_CLUSTER_TYPE_MAX - 1); } +/* on-disk sparse extent format */ +struct erofs_sparse_extent { + __le32 ee_lblk; + __le32 ee_pblk; + __le32 ee_len; +}; + +struct erofs_sparse_extent_iheader { + u32 count; +}; + #endif diff --git a/lib/inode.c b/lib/inode.c index 0e19b11..da20599 100644 --- a/lib/inode.c +++ b/lib/inode.c @@ -38,6 +38,97 @@ static unsigned char erofs_type_by_mode[S_IFMT >> S_SHIFT] = { struct list_head inode_hashtable[NR_INODE_HASHTABLE]; + +#define IS_HOLE(start, end) (roundup(start, EROFS_BLKSIZ) == start && \ + roundup(end, EROFS_BLKSIZ) == end && \ + (end - start) % EROFS_BLKSIZ == 0) + +/** + read extents of the given file. + record the data extents and link them into a chain. + exclude holes present in file. + */ +unsigned int erofs_read_sparse_extents(int fd, struct list_head *extents) +{ + erofs_blk_t startblk, endblk, datablk; + unsigned int nholes = 0; + erofs_off_t data, hole, len = 0, last_data; + struct erofs_sparse_extent_node *e_data; + + len = lseek(fd, 0, SEEK_END); + if (len < 0) + return -errno; + if (lseek(fd, 0, SEEK_SET) == -1) + return -errno; + data = 0; + last_data = 0; + while (data < len) { + hole = lseek(fd, data, SEEK_HOLE); + if (hole == len) + break; + data = lseek(fd, hole, SEEK_DATA); + if (data < 0 || hole > data) + return -EINVAL; + if (IS_HOLE(hole, data)) { + startblk = erofs_blknr(hole); + datablk = erofs_blknr(last_data); + endblk = erofs_blknr(data); + last_data = data; + e_data = malloc(sizeof( + struct erofs_sparse_extent_node)); + if (e_data == NULL) + return -ENOMEM; + e_data->lblk = datablk; + e_data->len = (startblk - datablk); + list_add_tail(&e_data->next, extents); + nholes += (endblk - startblk); + } + } + /* rounddown to exclude tail-end data */ + if (last_data < len && (len - last_data) >= EROFS_BLKSIZ) { + e_data = malloc(sizeof(struct erofs_sparse_extent_node)); + if (e_data == NULL) + return -ENOMEM; + startblk = erofs_blknr(last_data); + e_data->lblk = startblk; + e_data->len = erofs_blknr(rounddown((len - last_data), + EROFS_BLKSIZ)); + list_add_tail(&e_data->next, extents); + } + return nholes; +} + +int erofs_write_sparse_extents(struct erofs_inode *inode, erofs_off_t off) +{ + struct erofs_sparse_extent_node *e_node; + struct erofs_sparse_extent_iheader *header; + char *buf; + unsigned int p = 0; + int ret; + + buf = malloc(inode->sparse_extent_isize); + if (buf == NULL) + return -ENOMEM; + header = (struct erofs_sparse_extent_iheader *) buf; + header->count = 0; + p += sizeof(struct erofs_sparse_extent_iheader); + list_for_each_entry(e_node, &inode->i_sparse_extents, next) { + const struct erofs_sparse_extent ee = { + .ee_lblk = cpu_to_le32(e_node->lblk), + .ee_pblk = cpu_to_le32(e_node->pblk), + .ee_len = cpu_to_le32(e_node->len) + }; + memcpy(buf + p, &ee, sizeof(struct erofs_sparse_extent)); + p += sizeof(struct erofs_sparse_extent); + header->count++; + list_del(&e_node->next); + free(e_node); + } + ret = dev_write(buf, off, inode->sparse_extent_isize); + free(buf); + return ret; +} + void erofs_inode_manager_init(void) { unsigned int i; @@ -304,8 +395,9 @@ static bool erofs_file_is_compressible(struct erofs_inode *inode) int erofs_write_file(struct erofs_inode *inode) { - unsigned int nblocks, i; + unsigned int nblocks, i, j, nholes; int ret, fd; + struct erofs_sparse_extent_node *e_node; if (!inode->i_size) { inode->datalayout = EROFS_INODE_FLAT_PLAIN; @@ -322,31 +414,42 @@ int erofs_write_file(struct erofs_inode *inode) /* fallback to all data uncompressed */ inode->datalayout = EROFS_INODE_FLAT_INLINE; nblocks = inode->i_size / EROFS_BLKSIZ; - - ret = __allocate_inode_bh_data(inode, nblocks); - if (ret) - return ret; - fd = open(inode->i_srcpath, O_RDONLY | O_BINARY); if (fd < 0) return -errno; - - for (i = 0; i < nblocks; ++i) { - char buf[EROFS_BLKSIZ]; - - ret = read(fd, buf, EROFS_BLKSIZ); - if (ret != EROFS_BLKSIZ) { - if (ret < 0) + nholes = erofs_read_sparse_extents(fd, &inode->i_sparse_extents); + if (nholes < 0) { + close(fd); + return nholes; + } + ret = __allocate_inode_bh_data(inode, nblocks - nholes); + if (ret) { + close(fd); + return ret; + } + i = inode->u.i_blkaddr; + inode->sparse_extent_isize = sizeof(struct erofs_sparse_extent_iheader); + list_for_each_entry(e_node, &inode->i_sparse_extents, next) { + inode->sparse_extent_isize += sizeof(struct erofs_sparse_extent); + e_node->pblk = i; + ret = lseek(fd, blknr_to_addr(e_node->lblk), SEEK_SET); + if (ret < 0) + goto fail; + for (j = 0; j < e_node->len; j++) { + char buf[EROFS_BLKSIZ]; + ret = read(fd, buf, EROFS_BLKSIZ); + if (ret != EROFS_BLKSIZ) { + if (ret < 0) + goto fail; + close(fd); + return -EAGAIN; + } + ret = blk_write(buf, e_node->pblk + j, 1); + if (ret) goto fail; - close(fd); - return -EAGAIN; } - - ret = blk_write(buf, inode->u.i_blkaddr + i, 1); - if (ret) - goto fail; + i += e_node->len; } - /* read the tail-end data */ inode->idata_size = inode->i_size % EROFS_BLKSIZ; if (inode->idata_size) { @@ -479,8 +582,14 @@ static bool erofs_bh_flush_write_inode(struct erofs_buffer_head *bh) if (ret) return false; free(inode->compressmeta); + off += inode->extent_isize; } + if (inode->sparse_extent_isize) { + ret = erofs_write_sparse_extents(inode, off); + if (ret) + return false; + } inode->bh = NULL; erofs_iput(inode); return erofs_bh_flush_generic_end(bh); @@ -737,10 +846,11 @@ struct erofs_inode *erofs_new_inode(void) init_list_head(&inode->i_subdirs); init_list_head(&inode->i_xattrs); + init_list_head(&inode->i_sparse_extents); inode->idata_size = 0; inode->xattr_isize = 0; - inode->extent_isize = 0; + inode->sparse_extent_isize = 0; inode->bh = inode->bh_inline = inode->bh_data = NULL; inode->idata = NULL; @@ -961,4 +1071,3 @@ struct erofs_inode *erofs_mkfs_build_tree_from_path(struct erofs_inode *parent, return erofs_mkfs_build_tree(inode); } - -- 2.9.3
