static inline int nilfs_cpfile_get_checkpoint_block(struct inode *cpfile, __u64 cno, int create, struct buffer_head **bhp) { return nilfs_mdt_get_block(cpfile, nilfs_cpfile_get_blkoff(cpfile, cno), create, nilfs_cpfile_block_init, bhp); }
/** * nilfs_cpfile_find_checkpoint_block - find and get a buffer on cpfile * @cpfile: inode of cpfile * @start_cno: start checkpoint number (inclusive) * @end_cno: end checkpoint number (inclusive) * @cnop: place to store the next checkpoint number * @bhp: place to store a pointer to buffer_head struct * * Return Value: On success, it returns 0. On error, the following negative * error code is returned. * * %-ENOMEM - Insufficient memory available. * * %-EIO - I/O error * * %-ENOENT - no block exists in the range. */ static int nilfs_cpfile_find_checkpoint_block(struct inode *cpfile, __u64 start_cno, __u64 end_cno, __u64 *cnop, struct buffer_head **bhp) { unsigned long start, end, blkoff; int ret; if (unlikely(start_cno > end_cno)) return -ENOENT; start = nilfs_cpfile_get_blkoff(cpfile, start_cno); end = nilfs_cpfile_get_blkoff(cpfile, end_cno); ret = nilfs_mdt_find_block(cpfile, start, end, &blkoff, bhp); if (!ret) *cnop = (blkoff == start) ? start_cno : nilfs_cpfile_first_checkpoint_in_block(cpfile, blkoff); return ret; }
static inline int nilfs_cpfile_is_in_first(const struct inode *cpfile, __u64 cno) { return nilfs_cpfile_get_blkoff(cpfile, cno) == 0; }
static inline int nilfs_cpfile_delete_checkpoint_block(struct inode *cpfile, __u64 cno) { return nilfs_mdt_delete_block(cpfile, nilfs_cpfile_get_blkoff(cpfile, cno)); }
static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno) { struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh; struct nilfs_cpfile_header *header; struct nilfs_checkpoint *cp; struct nilfs_snapshot_list *list; __u64 curr, prev; unsigned long curr_blkoff, prev_blkoff; void *kaddr; int ret; if (cno == 0) return -ENOENT; /* checkpoint number 0 is invalid */ down_write(&NILFS_MDT(cpfile)->mi_sem); ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh); if (ret < 0) goto out_sem; kaddr = kmap_atomic(cp_bh->b_page); cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); if (nilfs_checkpoint_invalid(cp)) { ret = -ENOENT; kunmap_atomic(kaddr); goto out_cp; } if (nilfs_checkpoint_snapshot(cp)) { ret = 0; kunmap_atomic(kaddr); goto out_cp; } kunmap_atomic(kaddr); ret = nilfs_cpfile_get_header_block(cpfile, &header_bh); if (ret < 0) goto out_cp; kaddr = kmap_atomic(header_bh->b_page); header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr); list = &header->ch_snapshot_list; curr_bh = header_bh; get_bh(curr_bh); curr = 0; curr_blkoff = 0; prev = le64_to_cpu(list->ssl_prev); while (prev > cno) { prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev); curr = prev; if (curr_blkoff != prev_blkoff) { kunmap_atomic(kaddr); brelse(curr_bh); ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, 0, &curr_bh); if (ret < 0) goto out_header; kaddr = kmap_atomic(curr_bh->b_page); } curr_blkoff = prev_blkoff; cp = nilfs_cpfile_block_get_checkpoint( cpfile, curr, curr_bh, kaddr); list = &cp->cp_snapshot_list; prev = le64_to_cpu(list->ssl_prev); } kunmap_atomic(kaddr); if (prev != 0) { ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0, &prev_bh); if (ret < 0) goto out_curr; } else { prev_bh = header_bh; get_bh(prev_bh); } kaddr = kmap_atomic(curr_bh->b_page); list = nilfs_cpfile_block_get_snapshot_list( cpfile, curr, curr_bh, kaddr); list->ssl_prev = cpu_to_le64(cno); kunmap_atomic(kaddr); kaddr = kmap_atomic(cp_bh->b_page); cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); cp->cp_snapshot_list.ssl_next = cpu_to_le64(curr); cp->cp_snapshot_list.ssl_prev = cpu_to_le64(prev); nilfs_checkpoint_set_snapshot(cp); kunmap_atomic(kaddr); kaddr = kmap_atomic(prev_bh->b_page); list = nilfs_cpfile_block_get_snapshot_list( cpfile, prev, prev_bh, kaddr); list->ssl_next = cpu_to_le64(cno); kunmap_atomic(kaddr); kaddr = kmap_atomic(header_bh->b_page); header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr); le64_add_cpu(&header->ch_nsnapshots, 1); kunmap_atomic(kaddr); mark_buffer_dirty(prev_bh); mark_buffer_dirty(curr_bh); mark_buffer_dirty(cp_bh); mark_buffer_dirty(header_bh); nilfs_mdt_mark_dirty(cpfile); brelse(prev_bh); out_curr: brelse(curr_bh); out_header: brelse(header_bh); out_cp: brelse(cp_bh); out_sem: up_write(&NILFS_MDT(cpfile)->mi_sem); return ret; }
static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop, void *buf, unsigned int cisz, size_t nci) { struct buffer_head *bh; struct nilfs_cpfile_header *header; struct nilfs_checkpoint *cp; struct nilfs_cpinfo *ci = buf; __u64 curr = *cnop, next; unsigned long curr_blkoff, next_blkoff; void *kaddr; int n = 0, ret; down_read(&NILFS_MDT(cpfile)->mi_sem); if (curr == 0) { ret = nilfs_cpfile_get_header_block(cpfile, &bh); if (ret < 0) goto out; kaddr = kmap_atomic(bh->b_page); header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr); curr = le64_to_cpu(header->ch_snapshot_list.ssl_next); kunmap_atomic(kaddr); brelse(bh); if (curr == 0) { ret = 0; goto out; } } else if (unlikely(curr == ~(__u64)0)) { ret = 0; goto out; } curr_blkoff = nilfs_cpfile_get_blkoff(cpfile, curr); ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, 0, &bh); if (unlikely(ret < 0)) { if (ret == -ENOENT) ret = 0; /* No snapshots (started from a hole block) */ goto out; } kaddr = kmap_atomic(bh->b_page); while (n < nci) { cp = nilfs_cpfile_block_get_checkpoint(cpfile, curr, bh, kaddr); curr = ~(__u64)0; /* Terminator */ if (unlikely(nilfs_checkpoint_invalid(cp) || !nilfs_checkpoint_snapshot(cp))) break; nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, ci); ci = (void *)ci + cisz; n++; next = le64_to_cpu(cp->cp_snapshot_list.ssl_next); if (next == 0) break; /* reach end of the snapshot list */ next_blkoff = nilfs_cpfile_get_blkoff(cpfile, next); if (curr_blkoff != next_blkoff) { kunmap_atomic(kaddr); brelse(bh); ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, 0, &bh); if (unlikely(ret < 0)) { WARN_ON(ret == -ENOENT); goto out; } kaddr = kmap_atomic(bh->b_page); } curr = next; curr_blkoff = next_blkoff; } kunmap_atomic(kaddr); brelse(bh); *cnop = curr; ret = n; out: up_read(&NILFS_MDT(cpfile)->mi_sem); return ret; }