diff options
Diffstat (limited to 'fs/ocfs2/suballoc.c')
| -rw-r--r-- | fs/ocfs2/suballoc.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index 4c1399cc03f3..b4ca5911caaf 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -2185,3 +2185,162 @@ out: return ret; } + +/* + * Read the inode specified by blkno to get suballoc_slot and + * suballoc_bit. + */ +static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno, + u16 *suballoc_slot, u16 *suballoc_bit) +{ + int status; + struct buffer_head *inode_bh = NULL; + struct ocfs2_dinode *inode_fe; + + mlog_entry("blkno: %llu\n", blkno); + + /* dirty read disk */ + status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh); + if (status < 0) { + mlog(ML_ERROR, "read block %llu failed %d\n", blkno, status); + goto bail; + } + + inode_fe = (struct ocfs2_dinode *) inode_bh->b_data; + if (!OCFS2_IS_VALID_DINODE(inode_fe)) { + mlog(ML_ERROR, "invalid inode %llu requested\n", blkno); + status = -EINVAL; + goto bail; + } + + if (le16_to_cpu(inode_fe->i_suballoc_slot) != OCFS2_INVALID_SLOT && + (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) { + mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n", + blkno, (u32)le16_to_cpu(inode_fe->i_suballoc_slot)); + status = -EINVAL; + goto bail; + } + + if (suballoc_slot) + *suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot); + if (suballoc_bit) + *suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit); + +bail: + brelse(inode_bh); + + mlog_exit(status); + return status; +} + +/* + * test whether bit is SET in allocator bitmap or not. on success, 0 + * is returned and *res is 1 for SET; 0 otherwise. when fails, errno + * is returned and *res is meaningless. Call this after you have + * cluster locked against suballoc, or you may get a result based on + * non-up2date contents + */ +static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb, + struct inode *suballoc, + struct buffer_head *alloc_bh, u64 blkno, + u16 bit, int *res) +{ + struct ocfs2_dinode *alloc_fe; + struct ocfs2_group_desc *group; + struct buffer_head *group_bh = NULL; + u64 bg_blkno; + int status; + + mlog_entry("blkno: %llu bit: %u\n", blkno, (unsigned int)bit); + + alloc_fe = (struct ocfs2_dinode *)alloc_bh->b_data; + if ((bit + 1) > ocfs2_bits_per_group(&alloc_fe->id2.i_chain)) { + mlog(ML_ERROR, "suballoc bit %u out of range of %u\n", + (unsigned int)bit, + ocfs2_bits_per_group(&alloc_fe->id2.i_chain)); + status = -EINVAL; + goto bail; + } + + bg_blkno = ocfs2_which_suballoc_group(blkno, bit); + status = ocfs2_read_group_descriptor(suballoc, alloc_fe, bg_blkno, + &group_bh); + if (status < 0) { + mlog(ML_ERROR, "read group %llu failed %d\n", bg_blkno, status); + goto bail; + } + + group = (struct ocfs2_group_desc *) group_bh->b_data; + *res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap); + +bail: + brelse(group_bh); + + mlog_exit(status); + return status; +} + +/* + * Test if the bit representing this inode (blkno) is set in the + * suballocator. + * + * On success, 0 is returned and *res is 1 for SET; 0 otherwise. + * + * In the event of failure, a negative value is returned and *res is + * meaningless. + * + * Callers must make sure to hold nfs_sync_lock to prevent + * ocfs2_delete_inode() on another node from accessing the same + * suballocator concurrently. + */ +int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res) +{ + int status; + u16 suballoc_bit = 0, suballoc_slot = 0; + struct inode *inode_alloc_inode; + struct buffer_head *alloc_bh = NULL; + + mlog_entry("blkno: %llu", blkno); + + status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot, + &suballoc_bit); + if (status < 0) { + mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status); + goto bail; + } + + inode_alloc_inode = + ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE, + suballoc_slot); + if (!inode_alloc_inode) { + /* the error code could be inaccurate, but we are not able to + * get the correct one. */ + status = -EINVAL; + mlog(ML_ERROR, "unable to get alloc inode in slot %u\n", + (u32)suballoc_slot); + goto bail; + } + + mutex_lock(&inode_alloc_inode->i_mutex); + status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0); + if (status < 0) { + mutex_unlock(&inode_alloc_inode->i_mutex); + mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n", + (u32)suballoc_slot, status); + goto bail; + } + + status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh, + blkno, suballoc_bit, res); + if (status < 0) + mlog(ML_ERROR, "test suballoc bit failed %d\n", status); + + ocfs2_inode_unlock(inode_alloc_inode, 0); + mutex_unlock(&inode_alloc_inode->i_mutex); + + iput(inode_alloc_inode); + brelse(alloc_bh); +bail: + mlog_exit(status); + return status; +} |