// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "gfs2.h" #include "incore.h" #include "bmap.h" #include "glock.h" #include "log.h" #include "lops.h" #include "meta_io.h" #include "util.h" #include "dir.h" #include "trace_gfs2.h" #include "trans.h" static void gfs2_log_shutdown(struct gfs2_sbd *sdp); /** * gfs2_struct2blk - compute stuff * @sdp: the filesystem * @nstruct: the number of structures * * Compute the number of log descriptor blocks needed to hold a certain number * of structures of a certain size. * * Returns: the number of blocks needed (minimum is always 1) */ unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct) { unsigned int blks; unsigned int first, second; /* The initial struct gfs2_log_descriptor block */ blks = 1; first = sdp->sd_ldptrs; if (nstruct > first) { /* Subsequent struct gfs2_meta_header blocks */ second = sdp->sd_inptrs; blks += DIV_ROUND_UP(nstruct - first, second); } return blks; } /** * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters * @mapping: The associated mapping (maybe NULL) * @bd: The gfs2_bufdata to remove * * The ail lock _must_ be held when calling this function * */ void gfs2_remove_from_ail(struct gfs2_bufdata *bd) { bd->bd_tr = NULL; list_del_init(&bd->bd_ail_st_list); list_del_init(&bd->bd_ail_gl_list); atomic_dec(&bd->bd_gl->gl_ail_count); brelse(bd->bd_bh); } /** * gfs2_ail1_start_one - Start I/O on a part of the AIL * @sdp: the filesystem * @wbc: The writeback control structure * @ai: The ail structure * */ static int gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct writeback_control *wbc, struct gfs2_trans *tr, struct blk_plug *plug) __releases(&sdp->sd_ail_lock) __acquires(&sdp->sd_ail_lock) { struct gfs2_glock *gl = NULL; struct address_space *mapping; struct gfs2_bufdata *bd, *s; struct buffer_head *bh; int ret = 0; list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) { bh = bd->bd_bh; gfs2_assert(sdp, bd->bd_tr == tr); if (!buffer_busy(bh)) { if (buffer_uptodate(bh)) { list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list); continue; } if (!cmpxchg(&sdp->sd_log_error, 0, -EIO)) { gfs2_io_error_bh(sdp, bh); gfs2_withdraw_delayed(sdp); } } if (gfs2_withdrawn(sdp)) { gfs2_remove_from_ail(bd); continue; } if (!buffer_dirty(bh)) continue; if (gl == bd->bd_gl) continue; gl = bd->bd_gl; list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list); mapping = bh->b_page->mapping; if (!mapping) continue; spin_unlock(&sdp->sd_ail_lock); ret = generic_writepages(mapping, wbc); if (need_resched()) { blk_finish_plug(plug); cond_resched(); blk_start_plug(plug); } spin_lock(&sdp->sd_ail_lock); if (ret == -ENODATA) /* if a jdata write into a new hole */ ret = 0; /* ignore it */ if (ret || wbc->nr_to_write <= 0) break; return -EBUSY; } return ret; } static void dump_ail_list(struct gfs2_sbd *sdp) { struct gfs2_trans *tr; struct gfs2_bufdata *bd; struct buffer_head *bh; list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) { list_for_each_entry_reverse(bd, &tr->tr_ail1_list, bd_ail_st_list) { bh = bd->bd_bh; fs_err(sdp, "bd %p: blk:0x%llx bh=%p ", bd, (unsigned long long)bd->bd_blkno, bh); if (!bh) { fs_err(sdp, "\n"); continue; } fs_err(sdp, "0x%llx up2:%d dirt:%d lkd:%d req:%d " "map:%d new:%d ar:%d aw:%d delay:%d " "io err:%d unwritten:%d dfr:%d pin:%d esc:%d\n", (unsigned long long)bh->b_blocknr, buffer_uptodate(bh), buffer_dirty(bh), buffer_locked(bh), buffer_req(bh), buffer_mapped(bh), buffer_new(bh), buffer_async_read(bh), buffer_async_write(bh), buffer_delay(bh), buffer_write_io_error(bh), buffer_unwritten(bh), buffer_defer_completion(bh), buffer_pinned(bh), buffer_escaped(bh)); } } } /** * gfs2_ail1_flush - start writeback of some ail1 entries * @sdp: The super block * @wbc: The writeback control structure * * Writes back some ail1 entries, according to the limits in the * writeback control structure */ void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc) { struct list_head *head = &sdp->sd_ail1_list; struct gfs2_trans *tr; struct blk_plug plug; int ret; unsigned long flush_start = jiffies; trace_gfs2_ail_flush(sdp, wbc, 1); blk_start_plug(&plug); spin_lock(&sdp->sd_ail_lock); restart: ret = 0; if (time_after(jiffies, flush_start + (HZ * 600))) { fs_err(sdp, "Error: In %s for ten minutes! t=%d\n", __func__, current->journal_info ? 1 : 0); dump_ail_list(sdp); goto out; } list_for_each_entry_reverse(tr, head, tr_list) { if (wbc->nr_to_write <= 0) break; ret = gfs2_ail1_start_one(sdp, wbc, tr, &plug); if (ret) { if (ret == -EBUSY) goto restart; break; } } out: spin_unlock(&sdp->sd_ail_lock); blk_finish_plug(&plug); if (ret) { gfs2_lm(sdp, "gfs2_ail1_start_one (generic_writepages) " "returned: %d\n", ret); gfs2_withdraw(sdp); } trace_gfs2_ail_flush(sdp, wbc, 0); } /** * gfs2_ail1_start - start writeback of all ail1 entries * @sdp: The superblock */ static void gfs2_ail1_start(struct gfs2_sbd *sdp) { struct writeback_control wbc = { .sync_mode = WB_SYNC_NONE, .nr_to_write = LONG_MAX, .range_start = 0, .range_end = LLONG_MAX, }; return gfs2_ail1_flush(sdp, &wbc); } static void gfs2_log_update_flush_tail(struct gfs2_sbd *sdp) { unsigned int new_flush_tail = sdp->sd_log_head; struct gfs2_trans *tr; if (!list_empty(&sdp->sd_ail1_list)) { tr = list_last_entry(&sdp->sd_ail1_list, struct gfs2_trans, tr_list); new_flush_tail = tr->tr_first; } sdp->sd_log_flush_tail = new_flush_tail; } static void gfs2_log_update_head(struct gfs2_sbd *sdp) { unsigned int new_head = sdp->sd_log_flush_head; if (sdp->sd_log_flush_tail == sdp->sd_log_head) sdp->sd_log_flush_tail = new_head; sdp->sd_log_head = new_head; } /** * gfs2_ail_empty_tr - empty one of the ail lists of a transaction */ static void gfs2_ail_empty_tr(struct gfs2_sbd *sdp, struct gfs2_trans *tr, struct list_head *head) { struct gfs2_bufdata *bd; while (!list_empty(head)) { bd = list_first_entry(head, struct gfs2_bufdata, bd_ail_st_list); gfs2_assert(sdp, bd->bd_tr == tr); gfs2_remove_from_ail(bd); } } /** * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced * @sdp: the filesystem * @tr: the transaction * @max_revokes: If nonzero, issue revokes for the bd items for written buffers * * returns: the transaction's count of remaining active items */ static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr, int *max_revokes) { struct gfs2_bufdata *bd, *s; struct buffer_head *bh; int active_count = 0; list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) { bh = bd->bd_bh; gfs2_assert(sdp, bd->bd_tr == tr); /* * If another process flagged an io error, e.g. writing to the * journal, error all other bhs and move them off the ail1 to * prevent a tight loop when unmount tries to flush ail1, * regardless of whether they're still busy. If no outside * errors were found and the buffer is busy, move to the next. * If the ail buffer is not busy and caught an error, flag it * for others. */ if (!sdp->sd_log_error && buffer_busy(bh)) { active_count++; continue; } if (!buffer_uptodate(bh) && !cmpxchg(&sdp->sd_log_error, 0, -EIO)) { gfs2_io_error_bh(sdp, bh); gfs2_withdraw_delayed(sdp); } /* * If we have space for revokes and the bd is no longer on any * buf list, we can just add a revoke for it immediately and * avoid having to put it on the ail2 list, where it would need * to be revoked later. */ if (*max_revokes && list_empty(&bd->bd_list)) { gfs2_add_revoke(sdp, bd); (*max_revokes)--; continue; } list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list); } return active_count; } /** * gfs2_ail1_empty - Try to empty the ail1 lists * @sdp: The superblock * @max_revokes: If non-zero, add revokes where appropriate * * Tries to empty the ail1 lists, starting with the oldest first */ static int gfs2_ail1_empty(struct gfs2_sbd *sdp, int max_revokes) { struct gfs2_trans *tr, *s; int oldest_tr = 1; int ret; spin_lock(&sdp->sd_ail_lock); list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) { if (!gfs2_ail1_empty_one(sdp, tr, &max_revokes) && oldest_tr) list_move(&tr->tr_list, &sdp->sd_ail2_list); else oldest_tr = 0; } gfs2_log_update_flush_tail(sdp); ret = list_empty(&sdp->sd_ail1_list); spin_unlock(&sdp->sd_ail_lock); if (test_bit(SDF_WITHDRAWING, &sdp->sd_flags)) { gfs2_lm(sdp, "fatal: I/O error(s)\n"); gfs2_withdraw(sdp); } return ret; } static void gfs2_ail1_wait(struct gfs2_sbd *sdp) { struct gfs2_trans *tr; struct gfs2_bufdata *bd; struct buffer_head *bh; spin_lock(&sdp->sd_ail_lock); list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) { list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) { bh = bd->bd_bh; if (!buffer_locked(bh)) continue; get_bh(bh); spin_unlock(&sdp->sd_ail_lock); wait_on_buffer(bh); brelse(bh); return; } } spin_unlock(&sdp->sd_ail_lock); } static void __ail2_empty(struct gfs2_sbd *sdp, struct gfs2_trans *tr) { gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list); list_del(&tr->tr_list); gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list)); gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list)); gfs2_trans_free(sdp, tr); } static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail) { struct list_head *ail2_list = &sdp->sd_ail2_list; unsigned int old_tail = sdp->sd_log_tail; struct gfs2_trans *tr, *safe; spin_lock(&sdp->sd_ail_lock); if (old_tail <= new_tail) { list_for_each_entry_safe(tr, safe, ail2_list, tr_list) { if (old_tail <= tr->tr_first && tr->tr_first < new_tail) __ail2_empty(sdp, tr); } } else { list_for_each_entry_safe(tr, safe, ail2_list, tr_list) { if (old_tail <= tr->tr_first || tr->tr_first < new_tail) __ail2_empty(sdp, tr); } } spin_unlock(&sdp->sd_ail_lock); } /** * gfs2_log_is_empty - Check if the log is empty * @sdp: The GFS2 superblock */ bool gfs2_log_is_empty(struct gfs2_sbd *sdp) { return atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks; } static bool __gfs2_log_try_reserve_revokes(struct gfs2_sbd *sdp, unsigned int revokes) { unsigned int available; available = atomic_read(&sdp->sd_log_revokes_available); while (available >= revokes) { if (atomic_try_cmpxchg(&sdp->sd_log_revokes_available, &available, available - revokes)) return true; } return false; } /** * gfs2_log_release_revokes - Release a given number of revokes * @sdp: The GFS2 superblock * @revokes: The number of revokes to release * * sdp->sd_log_flush_lock must be held. */ void gfs2_log_release_revokes(struct gfs2_sbd *sdp, unsigned int revokes) { if (revokes) atomic_add(revokes, &sdp->sd_log_revokes_available); } /** * gfs2_log_release - Release a given number of log blocks * @sdp: The GFS2 superblock * @blks: The number of blocks * */ void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) { atomic_add(blks, &sdp->sd_log_blks_free); trace_gfs2_log_blocks(sdp, blks); gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks); if (atomic_read(&sdp->sd_log_blks_needed)) wake_up(&sdp->sd_log_waitq); } /** * __gfs2_log_try_reserve - Try to make a log reservation * @sdp: The GFS2 superblock * @blks: The number of blocks to reserve * @taboo_blks: The number of blocks to leave free * * Try to do the same as __gfs2_log_reserve(), but fail if no more log * space is immediately available. */ static bool __gfs2_log_try_reserve(struct gfs2_sbd *sdp, unsigned int blks, unsigned int taboo_blks) { unsigned wanted = blks + taboo_blks; unsigned int free_blocks; free_blocks = atomic_read(&sdp->sd_log_blks_free); while (free_blocks >= wanted) { if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks, free_blocks - blks)) { trace_gfs2_log_blocks(sdp, -blks); return true; } } return false; } /** * __gfs2_log_reserve - Make a log reservation * @sdp: The GFS2 superblock * @blks: The number of blocks to reserve * @taboo_blks: The number of blocks to leave free * * @taboo_blks is set to 0 for logd, and to GFS2_LOG_FLUSH_MIN_BLOCKS * for all other processes. This ensures that when the log is almost full, * logd will still be able to call gfs2_log_flush one more time without * blocking, which will advance the tail and make some more log space * available. * * We no longer flush the log here, instead we wake up logd to do that * for us. To avoid the thundering herd and to ensure that we deal fairly * with queued waiters, we use an exclusive wait. This means that when we * get woken with enough journal space to get our reservation, we need to * wake the next waiter on the list. */ static void __gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks, unsigned int taboo_blks) { unsigned wanted = blks + taboo_blks; unsigned int free_blocks; atomic_add(blks, &sdp->sd_log_blks_needed); for (;;) { if (current != sdp->sd_logd_process) wake_up(&sdp->sd_logd_waitq); io_wait_event(sdp->sd_log_waitq, (free_blocks = atomic_read(&sdp->sd_log_blks_free), free_blocks >= wanted)); do { if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks, free_blocks - blks)) goto reserved; } while (free_blocks >= wanted); } reserved: trace_gfs2_log_blocks(sdp, -blks); if (atomic_sub_return(blks, &sdp->sd_log_blks_needed)) wake_up(&sdp->sd_log_waitq); } /** * gfs2_log_try_reserve - Try to make a log reservation * @sdp: The GFS2 superblock * @tr: The transaction * @extra_revokes: The number of additional revokes reserved (output) * * This is similar to gfs2_log_reserve, but sdp->sd_log_flush_lock must be * held for correct revoke accounting. */ bool gfs2_log_try_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr, unsigned int *extra_revokes) { unsigned int blks = tr->tr_reserved; unsigned int revokes = tr->tr_revokes; unsigned int revoke_blks = 0; *extra_revokes = 0; if (revokes && !__gfs2_log_try_reserve_revokes(sdp, revokes)) { revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs); *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes; blks += revoke_blks; } if (!blks) return true; if (__gfs2_log_try_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS)) return true; if (!revoke_blks) gfs2_log_release_revokes(sdp, revokes); return false; } /** * gfs2_log_reserve - Make a log reservation * @sdp: The GFS2 superblock * @tr: The transaction * @extra_revokes: The number of additional revokes reserved (output) * * sdp->sd_log_flush_lock must not be held. */ void gfs2_log_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr, unsigned int *extra_revokes) { unsigned int blks = tr->tr_reserved; unsigned int revokes = tr->tr_revokes; unsigned int revoke_blks = 0; *extra_revokes = 0; if (revokes) { revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs); *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes; blks += revoke_blks; } __gfs2_log_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS); } /** * log_distance - Compute distance between two journal blocks * @sdp: The GFS2 superblock * @newer: The most recent journal block of the pair * @older: The older journal block of the pair * * Compute the distance (in the journal direction) between two * blocks in the journal * * Returns: the distance in blocks */ static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer, unsigned int older) { int dist; dist = newer - older; if (dist < 0) dist += sdp->sd_jdesc->jd_blocks; return dist; } /** * calc_reserved - Calculate the number of blocks to keep reserved * @sdp: The GFS2 superblock * * This is complex. We need to reserve room for all our currently used * metadata blocks (e.g. normal file I/O rewriting file time stamps) and * all our journaled data blocks for journaled files (e.g. files in the * meta_fs like rindex, or files for which chattr +j was done.) * If we don't reserve enough space, corruption will follow. * * We can have metadata blocks and jdata blocks in the same journal. Each * type gets its own log descriptor, for which we need to reserve a block. * In fact, each type has the potential for needing more than one log descriptor * in cases where we have more blocks than will fit in a log descriptor. * Metadata journal entries take up half the space of journaled buffer entries. * * Also, we need to reserve blocks for revoke journal entries and one for an * overall header for the lot. * * Returns: the number of blocks reserved */ static unsigned int calc_reserved(struct gfs2_sbd *sdp) { unsigned int reserved = GFS2_LOG_FLUSH_MIN_BLOCKS; unsigned int blocks; struct gfs2_trans *tr = sdp->sd_log_tr; if (tr) { blocks = tr->tr_num_buf_new - tr->tr_num_buf_rm; reserved += blocks + DIV_ROUND_UP(blocks, buf_limit(sdp)); blocks = tr->tr_num_databuf_new - tr->tr_num_databuf_rm; reserved += blocks + DIV_ROUND_UP(blocks, databuf_limit(sdp)); } return reserved; } static void log_pull_tail(struct gfs2_sbd *sdp) { unsigned int new_tail = sdp->sd_log_flush_tail; unsigned int dist; if (new_tail == sdp->sd_log_tail) return; dist = log_distance(sdp, new_tail, sdp->sd_log_tail); ail2_empty(sdp, new_tail); gfs2_log_release(sdp, dist); sdp->sd_log_tail = new_tail; } void log_flush_wait(struct gfs2_sbd *sdp) { DEFINE_WAIT(wait); if (atomic_read(&sdp->sd_log_in_flight)) { do { prepare_to_wait(&sdp->sd_log_flush_wait, &wait, TASK_UNINTERRUPTIBLE); if (atomic_read(&sdp->sd_log_in_flight)) io_schedule(); } while(atomic_read(&sdp->sd_log_in_flight)); finish_wait(&sdp->sd_log_flush_wait, &wait); } } static int ip_cmp(void *priv, struct list_head *a, struct list_head *b) { struct gfs2_inode *ipa, *ipb; ipa = list_entry(a, struct gfs2_inode, i_ordered); ipb = list_entry(b, struct gfs2_inode, i_ordered); if (ipa->i_no_addr < ipb->i_no_addr) return -1; if (ipa->i_no_addr > ipb->i_no_addr) return 1; return 0; } static void __ordered_del_inode(struct gfs2_inode *ip) { if (!list_empty(&ip->i_ordered)) list_del_init(&ip->i_ordered); } static void gfs2_ordered_write(struct gfs2_sbd *sdp) { struct gfs2_inode *ip; LIST_HEAD(written); spin_lock(&sdp->sd_ordered_lock); list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp); while (!list_empty(&sdp->sd_log_ordered)) { ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered); if (ip->i_inode.i_mapping->nrpages == 0) { __ordered_del_inode(ip); continue; } list_move(&ip->i_ordered, &written); spin_unlock(&sdp->sd_ordered_lock); filemap_fdatawrite(ip->i_inode.i_mapping); spin_lock(&sdp->sd_ordered_lock); } list_splice(&written, &sdp->sd_log_ordered); spin_unlock(&sdp->sd_ordered_lock); } static void gfs2_ordered_wait(struct gfs2_sbd *sdp) { struct gfs2_inode *ip; spin_lock(&sdp->sd_ordered_lock); while (!list_empty(&sdp->sd_log_ordered)) { ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered); __ordered_del_inode(ip); if (ip->i_inode.i_mapping->nrpages == 0) continue; spin_unlock(&sdp->sd_ordered_lock); filemap_fdatawait(ip->i_inode.i_mapping); spin_lock(&sdp->sd_ordered_lock); } spin_unlock(&sdp->sd_ordered_lock); } void gfs2_ordered_del_inode(struct gfs2_inode *ip) { struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); spin_lock(&sdp->sd_ordered_lock); __ordered_del_inode(ip); spin_unlock(&sdp->sd_ordered_lock); } void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd) { struct buffer_head *bh = bd->bd_bh; struct gfs2_glock *gl = bd->bd_gl; sdp->sd_log_num_revoke++; if (atomic_inc_return(&gl->gl_revokes) == 1) gfs2_glock_hold(gl); bh->b_private = NULL; bd->bd_blkno = bh->b_blocknr; gfs2_remove_from_ail(bd); /* drops ref on bh */ bd->bd_bh = NULL; set_bit(GLF_LFLUSH, &gl->gl_flags); list_add(&bd->bd_list, &sdp->sd_log_revokes); } void gfs2_glock_remove_revoke(struct gfs2_glock *gl) { if (atomic_dec_return(&gl->gl_revokes) == 0) { clear_bit(GLF_LFLUSH, &gl->gl_flags); gfs2_glock_queue_put(gl); } } /** * gfs2_flush_revokes - Add as many revokes to the system transaction as we can * @sdp: The GFS2 superblock * * Our usual strategy is to defer writing revokes as much as we can in the hope * that we'll eventually overwrite the journal, which will make those revokes * go away. This changes when we flush the log: at that point, there will * likely be some left-over space in the last revoke block of that transaction. * We can fill that space with additional revokes for blocks that have already * been written back. This will basically come at no cost now, and will save * us from having to keep track of those blocks on the AIL2 list later. */ void gfs2_flush_revokes(struct gfs2_sbd *sdp) { /* number of revokes we still have room for */ unsigned int max_revokes = atomic_read(&sdp->sd_log_revokes_available); gfs2_log_lock(sdp); gfs2_ail1_empty(sdp, max_revokes); gfs2_log_unlock(sdp); } /** * gfs2_write_log_header - Write a journal log header buffer at lblock * @sdp: The GFS2 superblock * @jd: journal descriptor of the journal to which we are writing * @seq: sequence number * @tail: tail of the log * @lblock: value for lh_blkno (block number relative to start of journal) * @flags: log header flags GFS2_LOG_HEAD_* * @op_flags: flags to pass to the bio * * Returns: the initialized log buffer descriptor */ void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd, u64 seq, u32 tail, u32 lblock, u32 flags, int op_flags) { struct gfs2_log_header *lh; u32 hash, crc; struct page *page; struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local; struct timespec64 tv; struct super_block *sb = sdp->sd_vfs; u64 dblock; if (gfs2_withdrawn(sdp)) return; page = mempool_alloc(gfs2_page_pool, GFP_NOIO); lh = page_address(page); clear_page(lh); lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH); lh->lh_header.__pad0 = cpu_to_be64(0); lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH); lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); lh->lh_sequence = cpu_to_be64(seq); lh->lh_flags = cpu_to_be32(flags); lh->lh_tail = cpu_to_be32(tail); lh->lh_blkno = cpu_to_be32(lblock); hash = ~crc32(~0, lh, LH_V1_SIZE); lh->lh_hash = cpu_to_be32(hash); ktime_get_coarse_real_ts64(&tv); lh->lh_nsec = cpu_to_be32(tv.tv_nsec); lh->lh_sec = cpu_to_be64(tv.tv_sec); if (!list_empty(&jd->extent_list)) dblock = gfs2_log_bmap(jd, lblock); else { unsigned int extlen; int ret; extlen = 1; ret = gfs2_get_extent(jd->jd_inode, lblock, &dblock, &extlen); if (gfs2_assert_withdraw(sdp, ret == 0)) return; } lh->lh_addr = cpu_to_be64(dblock); lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr); /* We may only write local statfs, quota, etc., when writing to our own journal. The values are left 0 when recovering a journal different from our own. */ if (!(flags & GFS2_LOG_HEAD_RECOVERY)) { lh->lh_statfs_addr = cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr); lh->lh_quota_addr = cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr); spin_lock(&sdp->sd_statfs_spin); lh->lh_local_total = cpu_to_be64(l_sc->sc_total); lh->lh_local_free = cpu_to_be64(l_sc->sc_free); lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes); spin_unlock(&sdp->sd_statfs_spin); } BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE); crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4, sb->s_blocksize - LH_V1_SIZE - 4); lh->lh_crc = cpu_to_be32(crc); gfs2_log_write(sdp, jd, page, sb->s_blocksize, 0, dblock); gfs2_log_submit_bio(&jd->jd_log_bio, REQ_OP_WRITE | op_flags); } /** * log_write_header - Get and initialize a journal header buffer * @sdp: The GFS2 superblock * @flags: The log header flags, including log header origin * * Returns: the initialized log buffer descriptor */ static void log_write_header(struct gfs2_sbd *sdp, u32 flags) { int op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC; enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state); gfs2_assert_withdraw(sdp, (state != SFS_FROZEN)); if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) { gfs2_ordered_wait(sdp); log_flush_wait(sdp); op_flags = REQ_SYNC | REQ_META | REQ_PRIO; } sdp->sd_log_idle = (sdp->sd_log_flush_tail == sdp->sd_log_flush_head); gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++, sdp->sd_log_flush_tail, sdp->sd_log_flush_head, flags, op_flags); gfs2_log_incr_head(sdp); log_flush_wait(sdp); log_pull_tail(sdp); gfs2_log_update_head(sdp); } /** * ail_drain - drain the ail lists after a withdraw * @sdp: Pointer to GFS2 superblock */ static void ail_drain(struct gfs2_sbd *sdp) { struct gfs2_trans *tr; spin_lock(&sdp->sd_ail_lock); /* * For transactions on the sd_ail1_list we need to drain both the * ail1 and ail2 lists. That's because function gfs2_ail1_start_one * (temporarily) moves items from its tr_ail1 list to tr_ail2 list * before revokes are sent for that block. Items on the sd_ail2_list * should have already gotten beyond that point, so no need. */ while (!list_empty(&sdp->sd_ail1_list)) { tr = list_first_entry(&sdp->sd_ail1_list, struct gfs2_trans, tr_list); gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail1_list); gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list); list_del(&tr->tr_list); gfs2_trans_free(sdp, tr); } while (!list_empty(&sdp->sd_ail2_list)) { tr = list_first_entry(&sdp->sd_ail2_list, struct gfs2_trans, tr_list); gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list); list_del(&tr->tr_list); gfs2_trans_free(sdp, tr); } spin_unlock(&sdp->sd_ail_lock); } /** * empty_ail1_list - try to start IO and empty the ail1 list * @sdp: Pointer to GFS2 superblock */ static void empty_ail1_list(struct gfs2_sbd *sdp) { unsigned long start = jiffies; for (;;) { if (time_after(jiffies, start + (HZ * 600))) { fs_err(sdp, "Error: In %s for 10 minutes! t=%d\n", __func__, current->journal_info ? 1 : 0); dump_ail_list(sdp); return; } gfs2_ail1_start(sdp); gfs2_ail1_wait(sdp); if (gfs2_ail1_empty(sdp, 0)) return; } } /** * trans_drain - drain the buf and databuf queue for a failed transaction * @tr: the transaction to drain * * When this is called, we're taking an error exit for a log write that failed * but since we bypassed the after_commit functions, we need to remove the * items from the buf and databuf queue. */ static void trans_drain(struct gfs2_trans *tr) { struct gfs2_bufdata *bd; struct list_head *head; if (!tr) return; head = &tr->tr_buf; while (!list_empty(head)) { bd = list_first_entry(head, struct gfs2_bufdata, bd_list); list_del_init(&bd->bd_list); if (!list_empty(&bd->bd_ail_st_list)) gfs2_remove_from_ail(bd); kmem_cache_free(gfs2_bufdata_cachep, bd); } head = &tr->tr_databuf; while (!list_empty(head)) { bd = list_first_entry(head, struct gfs2_bufdata, bd_list); list_del_init(&bd->bd_list); if (!list_empty(&bd->bd_ail_st_list)) gfs2_remove_from_ail(bd); kmem_cache_free(gfs2_bufdata_cachep, bd); } } /** * gfs2_log_flush - flush incore transaction(s) * @sdp: the filesystem * @gl: The glock structure to flush. If NULL, flush the whole incore log * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags * */ void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags) { struct gfs2_trans *tr = NULL; unsigned int reserved_blocks = 0, used_blocks = 0; enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state); unsigned int first_log_head; unsigned int reserved_revokes = 0; down_write(&sdp->sd_log_flush_lock); trace_gfs2_log_flush(sdp, 1, flags); repeat: /* * Do this check while holding the log_flush_lock to prevent new * buffers from being added to the ail via gfs2_pin() */ if (gfs2_withdrawn(sdp) || !test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) goto out; /* Log might have been flushed while we waited for the flush lock */ if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) goto out; first_log_head = sdp->sd_log_head; sdp->sd_log_flush_head = first_log_head; tr = sdp->sd_log_tr; if (tr || sdp->sd_log_num_revoke) { if (reserved_blocks) gfs2_log_release(sdp, reserved_blocks); reserved_blocks = sdp->sd_log_blks_reserved; reserved_revokes = sdp->sd_log_num_revoke; if (tr) { sdp->sd_log_tr = NULL; tr->tr_first = first_log_head; if (unlikely (state == SFS_FROZEN)) { if (gfs2_assert_withdraw_delayed(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new)) goto out_withdraw; } } } else if (!reserved_blocks) { unsigned int taboo_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS; reserved_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS; if (current == sdp->sd_logd_process) taboo_blocks = 0; if (!__gfs2_log_try_reserve(sdp, reserved_blocks, taboo_blocks)) { up_write(&sdp->sd_log_flush_lock); __gfs2_log_reserve(sdp, reserved_blocks, taboo_blocks); down_write(&sdp->sd_log_flush_lock); goto repeat; } BUG_ON(sdp->sd_log_num_revoke); } if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN) clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags); if (unlikely(state == SFS_FROZEN)) if (gfs2_assert_withdraw_delayed(sdp, !reserved_revokes)) goto out_withdraw; gfs2_ordered_write(sdp); if (gfs2_withdrawn(sdp)) goto out_withdraw; lops_before_commit(sdp, tr); if (gfs2_withdrawn(sdp)) goto out_withdraw; gfs2_log_submit_bio(&sdp->sd_jdesc->jd_log_bio, REQ_OP_WRITE); if (gfs2_withdrawn(sdp)) goto out_withdraw; if (sdp->sd_log_head != sdp->sd_log_flush_head) { log_write_header(sdp, flags); } else if (sdp->sd_log_tail != sdp->sd_log_flush_tail && !sdp->sd_log_idle) { log_write_header(sdp, flags); } if (gfs2_withdrawn(sdp)) goto out_withdraw; lops_after_commit(sdp, tr); gfs2_log_lock(sdp); sdp->sd_log_blks_reserved = 0; spin_lock(&sdp->sd_ail_lock); if (tr && !list_empty(&tr->tr_ail1_list)) { list_add(&tr->tr_list, &sdp->sd_ail1_list); tr = NULL; } spin_unlock(&sdp->sd_ail_lock); gfs2_log_unlock(sdp); if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) { if (!sdp->sd_log_idle) { empty_ail1_list(sdp); if (gfs2_withdrawn(sdp)) goto out_withdraw; log_write_header(sdp, flags); } if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN | GFS2_LOG_HEAD_FLUSH_FREEZE)) gfs2_log_shutdown(sdp); if (flags & GFS2_LOG_HEAD_FLUSH_FREEZE) atomic_set(&sdp->sd_freeze_state, SFS_FROZEN); } out_end: used_blocks = log_distance(sdp, sdp->sd_log_flush_head, first_log_head); reserved_revokes += atomic_read(&sdp->sd_log_revokes_available); atomic_set(&sdp->sd_log_revokes_available, sdp->sd_ldptrs); gfs2_assert_withdraw(sdp, reserved_revokes % sdp->sd_inptrs == sdp->sd_ldptrs); if (reserved_revokes > sdp->sd_ldptrs) reserved_blocks += (reserved_revokes - sdp->sd_ldptrs) / sdp->sd_inptrs; out: if (used_blocks != reserved_blocks) { gfs2_assert_withdraw_delayed(sdp, used_blocks < reserved_blocks); gfs2_log_release(sdp, reserved_blocks - used_blocks); } up_write(&sdp->sd_log_flush_lock); gfs2_trans_free(sdp, tr); if (gfs2_withdrawing(sdp)) gfs2_withdraw(sdp); trace_gfs2_log_flush(sdp, 0, flags); return; out_withdraw: trans_drain(tr); /** * If the tr_list is empty, we're withdrawing during a log * flush that targets a transaction, but the transaction was * never queued onto any of the ail lists. Here we add it to * ail1 just so that ail_drain() will find and free it. */ spin_lock(&sdp->sd_ail_lock); if (tr && list_empty(&tr->tr_list)) list_add(&tr->tr_list, &sdp->sd_ail1_list); spin_unlock(&sdp->sd_ail_lock); ail_drain(sdp); /* frees all transactions */ tr = NULL; goto out_end; } /** * gfs2_merge_trans - Merge a new transaction into a cached transaction * @old: Original transaction to be expanded * @new: New transaction to be merged */ static void gfs2_merge_trans(struct gfs2_sbd *sdp, struct gfs2_trans *new) { struct gfs2_trans *old = sdp->sd_log_tr; WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags)); old->tr_num_buf_new += new->tr_num_buf_new; old->tr_num_databuf_new += new->tr_num_databuf_new; old->tr_num_buf_rm += new->tr_num_buf_rm; old->tr_num_databuf_rm += new->tr_num_databuf_rm; old->tr_revokes += new->tr_revokes; old->tr_num_revoke += new->tr_num_revoke; list_splice_tail_init(&new->tr_databuf, &old->tr_databuf); list_splice_tail_init(&new->tr_buf, &old->tr_buf); spin_lock(&sdp->sd_ail_lock); list_splice_tail_init(&new->tr_ail1_list, &old->tr_ail1_list); list_splice_tail_init(&new->tr_ail2_list, &old->tr_ail2_list); spin_unlock(&sdp->sd_ail_lock); } static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) { unsigned int reserved; unsigned int unused; unsigned int maxres; gfs2_log_lock(sdp); if (sdp->sd_log_tr) { gfs2_merge_trans(sdp, tr); } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) { gfs2_assert_withdraw(sdp, !test_bit(TR_ONSTACK, &tr->tr_flags)); sdp->sd_log_tr = tr; set_bit(TR_ATTACHED, &tr->tr_flags); } reserved = calc_reserved(sdp); maxres = sdp->sd_log_blks_reserved + tr->tr_reserved; gfs2_assert_withdraw(sdp, maxres >= reserved); unused = maxres - reserved; if (unused) gfs2_log_release(sdp, unused); sdp->sd_log_blks_reserved = reserved; gfs2_log_unlock(sdp); } /** * gfs2_log_commit - Commit a transaction to the log * @sdp: the filesystem * @tr: the transaction * * We wake up gfs2_logd if the number of pinned blocks exceed thresh1 * or the total number of used blocks (pinned blocks plus AIL blocks) * is greater than thresh2. * * At mount time thresh1 is 2/5ths of journal size, thresh2 is 4/5ths of * journal size. * * Returns: errno */ void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) { log_refund(sdp, tr); if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) || ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) > atomic_read(&sdp->sd_log_thresh2))) wake_up(&sdp->sd_logd_waitq); } /** * gfs2_log_shutdown - write a shutdown header into a journal * @sdp: the filesystem * */ static void gfs2_log_shutdown(struct gfs2_sbd *sdp) { gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved); gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list)); log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN); log_pull_tail(sdp); gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail); gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list)); } static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp) { return (atomic_read(&sdp->sd_log_pinned) + atomic_read(&sdp->sd_log_blks_needed) >= atomic_read(&sdp->sd_log_thresh1)); } static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp) { unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free); if (test_and_clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags)) return 1; return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >= atomic_read(&sdp->sd_log_thresh2); } /** * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks * @sdp: Pointer to GFS2 superblock * * Also, periodically check to make sure that we're using the most recent * journal index. */ int gfs2_logd(void *data) { struct gfs2_sbd *sdp = data; unsigned long t = 1; DEFINE_WAIT(wait); while (!kthread_should_stop()) { if (gfs2_withdrawn(sdp)) { msleep_interruptible(HZ); continue; } /* Check for errors writing to the journal */ if (sdp->sd_log_error) { gfs2_lm(sdp, "GFS2: fsid=%s: error %d: " "withdrawing the file system to " "prevent further damage.\n", sdp->sd_fsname, sdp->sd_log_error); gfs2_withdraw(sdp); continue; } if (gfs2_jrnl_flush_reqd(sdp) || t == 0) { gfs2_ail1_empty(sdp, 0); gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_LOGD_JFLUSH_REQD); } if (gfs2_ail_flush_reqd(sdp)) { gfs2_ail1_start(sdp); gfs2_ail1_wait(sdp); gfs2_ail1_empty(sdp, 0); gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_LOGD_AIL_FLUSH_REQD); } t = gfs2_tune_get(sdp, gt_logd_secs) * HZ; try_to_freeze(); do { prepare_to_wait(&sdp->sd_logd_waitq, &wait, TASK_INTERRUPTIBLE); if (!gfs2_ail_flush_reqd(sdp) && !gfs2_jrnl_flush_reqd(sdp) && !kthread_should_stop()) t = schedule_timeout(t); } while(t && !gfs2_ail_flush_reqd(sdp) && !gfs2_jrnl_flush_reqd(sdp) && !kthread_should_stop()); finish_wait(&sdp->sd_logd_waitq, &wait); } return 0; }