/* * Interface between ext4 and JBD */ #include "ext4_jbd2.h" #include <trace/events/ext4.h> /* Just increment the non-pointer handle value */ static handle_t *ext4_get_nojournal(void) { handle_t *handle = current->journal_info; unsigned long ref_cnt = (unsigned long)handle; BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT); ref_cnt++; handle = (handle_t *)ref_cnt; current->journal_info = handle; return handle; } /* Decrement the non-pointer handle value */ static void ext4_put_nojournal(handle_t *handle) { unsigned long ref_cnt = (unsigned long)handle; BUG_ON(ref_cnt == 0); ref_cnt--; handle = (handle_t *)ref_cnt; current->journal_info = handle; } /* * Wrappers for jbd2_journal_start/end. */ static int ext4_journal_check_start(struct super_block *sb) { journal_t *journal; might_sleep(); if (sb->s_flags & MS_RDONLY) return -EROFS; WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); journal = EXT4_SB(sb)->s_journal; /* * Special case here: if the journal has aborted behind our * backs (eg. EIO in the commit thread), then we still need to * take the FS itself readonly cleanly. */ if (journal && is_journal_aborted(journal)) { ext4_abort(sb, "Detected aborted journal"); return -EROFS; } return 0; } handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, int type, int blocks, int rsv_blocks) { journal_t *journal; int err; trace_ext4_journal_start(sb, blocks, rsv_blocks, _RET_IP_); err = ext4_journal_check_start(sb); if (err < 0) return ERR_PTR(err); journal = EXT4_SB(sb)->s_journal; if (!journal) return ext4_get_nojournal(); return jbd2__journal_start(journal, blocks, rsv_blocks, GFP_NOFS, type, line); } int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) { struct super_block *sb; int err; int rc; if (!ext4_handle_valid(handle)) { ext4_put_nojournal(handle); return 0; } if (!handle->h_transaction) { err = jbd2_journal_stop(handle); return handle->h_err ? handle->h_err : err; } sb = handle->h_transaction->t_journal->j_private; err = handle->h_err; rc = jbd2_journal_stop(handle); if (!err) err = rc; if (err) __ext4_std_error(sb, where, line, err); return err; } handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, int type) { struct super_block *sb; int err; if (!ext4_handle_valid(handle)) return ext4_get_nojournal(); sb = handle->h_journal->j_private; trace_ext4_journal_start_reserved(sb, handle->h_buffer_credits, _RET_IP_); err = ext4_journal_check_start(sb); if (err < 0) { jbd2_journal_free_reserved(handle); return ERR_PTR(err); } err = jbd2_journal_start_reserved(handle, type, line); if (err < 0) return ERR_PTR(err); return handle; } static void ext4_journal_abort_handle(const char *caller, unsigned int line, const char *err_fn, struct buffer_head *bh, handle_t *handle, int err) { char nbuf[16]; const char *errstr = ext4_decode_error(NULL, err, nbuf); BUG_ON(!ext4_handle_valid(handle)); if (bh) BUFFER_TRACE(bh, "abort"); if (!handle->h_err) handle->h_err = err; if (is_handle_aborted(handle)) return; printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n", caller, line, errstr, err_fn); jbd2_journal_abort_handle(handle); } int __ext4_journal_get_write_access(const char *where, unsigned int line, handle_t *handle, struct buffer_head *bh) { int err = 0; might_sleep(); if (ext4_handle_valid(handle)) { err = jbd2_journal_get_write_access(handle, bh); if (err) ext4_journal_abort_handle(where, line, __func__, bh, handle, err); } return err; } /* * The ext4 forget function must perform a revoke if we are freeing data * which has been journaled. Metadata (eg. indirect blocks) must be * revoked in all cases. * * "bh" may be NULL: a metadata block may have been freed from memory * but there may still be a record of it in the journal, and that record * still needs to be revoked. * * If the handle isn't valid we're not journaling, but we still need to * call into ext4_journal_revoke() to put the buffer head. */ int __ext4_forget(const char *where, unsigned int line, handle_t *handle, int is_metadata, struct inode *inode, struct buffer_head *bh, ext4_fsblk_t blocknr) { int err; might_sleep(); trace_ext4_forget(inode, is_metadata, blocknr); BUFFER_TRACE(bh, "enter"); jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " "data mode %x\n", bh, is_metadata, inode->i_mode, test_opt(inode->i_sb, DATA_FLAGS)); /* In the no journal case, we can just do a bforget and return */ if (!ext4_handle_valid(handle)) { bforget(bh); return 0; } /* Never use the revoke function if we are doing full data * journaling: there is no need to, and a V1 superblock won't * support it. Otherwise, only skip the revoke on un-journaled * data blocks. */ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || (!is_metadata && !ext4_should_journal_data(inode))) { if (bh) { BUFFER_TRACE(bh, "call jbd2_journal_forget"); err = jbd2_journal_forget(handle, bh); if (err) ext4_journal_abort_handle(where, line, __func__, bh, handle, err); return err; } return 0; } /* * data!=journal && (is_metadata || should_journal_data(inode)) */ BUFFER_TRACE(bh, "call jbd2_journal_revoke"); err = jbd2_journal_revoke(handle, blocknr, bh); if (err) { ext4_journal_abort_handle(where, line, __func__, bh, handle, err); __ext4_abort(inode->i_sb, where, line, "error %d when attempting revoke", err); } BUFFER_TRACE(bh, "exit"); return err; } int __ext4_journal_get_create_access(const char *where, unsigned int line, handle_t *handle, struct buffer_head *bh) { int err = 0; if (ext4_handle_valid(handle)) { err = jbd2_journal_get_create_access(handle, bh); if (err) ext4_journal_abort_handle(where, line, __func__, bh, handle, err); } return err; } int __ext4_handle_dirty_metadata(const char *where, unsigned int line, handle_t *handle, struct inode *inode, struct buffer_head *bh) { int err = 0; might_sleep(); set_buffer_meta(bh); set_buffer_prio(bh); if (ext4_handle_valid(handle)) { err = jbd2_journal_dirty_metadata(handle, bh); /* Errors can only happen due to aborted journal or a nasty bug */ if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) { ext4_journal_abort_handle(where, line, __func__, bh, handle, err); if (inode == NULL) { pr_err("EXT4: jbd2_journal_dirty_metadata " "failed: handle type %u started at " "line %u, credits %u/%u, errcode %d", handle->h_type, handle->h_line_no, handle->h_requested_credits, handle->h_buffer_credits, err); return err; } ext4_error_inode(inode, where, line, bh->b_blocknr, "journal_dirty_metadata failed: " "handle type %u started at line %u, " "credits %u/%u, errcode %d", handle->h_type, handle->h_line_no, handle->h_requested_credits, handle->h_buffer_credits, err); } } else { if (inode) mark_buffer_dirty_inode(bh, inode); else mark_buffer_dirty(bh); if (inode && inode_needs_sync(inode)) { sync_dirty_buffer(bh); if (buffer_req(bh) && !buffer_uptodate(bh)) { struct ext4_super_block *es; es = EXT4_SB(inode->i_sb)->s_es; es->s_last_error_block = cpu_to_le64(bh->b_blocknr); ext4_error_inode(inode, where, line, bh->b_blocknr, "IO error syncing itable block"); err = -EIO; } } } return err; } int __ext4_handle_dirty_super(const char *where, unsigned int line, handle_t *handle, struct super_block *sb) { struct buffer_head *bh = EXT4_SB(sb)->s_sbh; int err = 0; ext4_superblock_csum_set(sb); if (ext4_handle_valid(handle)) { err = jbd2_journal_dirty_metadata(handle, bh); if (err) ext4_journal_abort_handle(where, line, __func__, bh, handle, err); } else mark_buffer_dirty(bh); return err; }