/* * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2022 Tomohiro Kusumi <tkusumi@netbsd.org> * Copyright (c) 2011-2022 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project * by Matthew Dillon <dillon@dragonflybsd.org> * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name of The DragonFly Project nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific, prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * TRANSACTION AND FLUSH HANDLING * * Deceptively simple but actually fairly difficult to implement properly is * how I would describe it. * * Flushing generally occurs bottom-up but requires a top-down scan to * locate chains with MODIFIED and/or UPDATE bits set. The ONFLUSH flag * tells how to recurse downward to find these chains. */ /* #include <sys/cdefs.h> #include <sys/param.h> #include <sys/systm.h> #include <sys/types.h> #include <sys/lock.h> #include <sys/vnode.h> #include <sys/buf.h> */ #include "hammer2.h" #define HAMMER2_FLUSH_DEPTH_LIMIT 60 /* stack recursion limit */ /* * Recursively flush the specified chain. The chain is locked and * referenced by the caller and will remain so on return. The chain * will remain referenced throughout but can temporarily lose its * lock during the recursion to avoid unnecessarily stalling user * processes. */ struct hammer2_flush_info { hammer2_chain_t *parent; int depth; int error; /* cumulative error */ int flags; #ifdef HAMMER2_SCAN_DEBUG long scan_count; long scan_mod_count; long scan_upd_count; long scan_onf_count; long scan_del_count; long scan_btype[7]; #endif }; typedef struct hammer2_flush_info hammer2_flush_info_t; static int hammer2_flush_core(hammer2_flush_info_t *info, hammer2_chain_t *chain, int flags); static int hammer2_flush_recurse(hammer2_chain_t *child, void *data); /* * Any per-pfs transaction initialization goes here. */ void hammer2_trans_manage_init(hammer2_pfs_t *pmp) { } /* * Transaction support for any modifying operation. Transactions are used * in the pmp layer by the frontend and in the spmp layer by the backend. * * 0 - Normal transaction. Interlocks against just the * COPYQ portion of an ISFLUSH transaction. * * TRANS_ISFLUSH - Flush transaction. Interlocks against other flush * transactions. * * When COPYQ is also specified, waits for the count * to drop to 1. * * TRANS_BUFCACHE - Buffer cache transaction. No interlock. * * TRANS_SIDEQ - Run the sideq (only tested in trans_done()) * * Initializing a new transaction allocates a transaction ID. Typically * passed a pmp (hmp passed as NULL), indicating a cluster transaction. Can * be passed a NULL pmp and non-NULL hmp to indicate a transaction on a single * media target. The latter mode is used by the recovery code. */ void hammer2_trans_init(hammer2_pfs_t *pmp, uint32_t flags) { uint32_t oflags; uint32_t nflags; int dowait; for (;;) { oflags = pmp->trans.flags; cpu_ccfence(); dowait = 0; if (flags & HAMMER2_TRANS_ISFLUSH) { /* * Interlock against other flush transactions. */ if (oflags & HAMMER2_TRANS_ISFLUSH) { nflags = oflags | HAMMER2_TRANS_WAITING; dowait = 1; } else { nflags = (oflags | flags) + 1; } } else if (flags & HAMMER2_TRANS_BUFCACHE) { /* * Requesting strategy transaction from buffer-cache, * or a VM getpages/putpages through the buffer cache. * We must allow such transactions in all situations * to avoid deadlocks. */ nflags = (oflags | flags) + 1; } else { /* * Normal transaction. We do not interlock against * BUFCACHE or ISFLUSH. * * Note that vnode locks may be held going into * this call. * * NOTE: Remember that non-modifying operations * such as read, stat, readdir, etc, do * not use transactions. */ nflags = (oflags | flags) + 1; } if (dowait) tsleep_interlock(&pmp->trans.sync_wait, 0); if (atomic_cmpset_int(&pmp->trans.flags, oflags, nflags)) { if (dowait == 0) break; tsleep(&pmp->trans.sync_wait, PINTERLOCKED, "h2trans", hz); /* retry */ } else { cpu_pause(); /* retry */ } /* retry */ } #if 0 /* * When entering a FLUSH transaction with COPYQ set, wait for the * transaction count to drop to 1 (our flush transaction only) * before proceeding. * * This waits for all non-flush transactions to complete and blocks * new non-flush transactions from starting until COPYQ is cleared. * (the flush will then proceed after clearing COPYQ). This should * be a very short stall on modifying operations. */ while ((flags & HAMMER2_TRANS_ISFLUSH) && (flags & HAMMER2_TRANS_COPYQ)) { oflags = pmp->trans.flags; cpu_ccfence(); if ((oflags & HAMMER2_TRANS_MASK) == 1) break; nflags = oflags | HAMMER2_TRANS_WAITING; tsleep_interlock(&pmp->trans.sync_wait, 0); if (atomic_cmpset_int(&pmp->trans.flags, oflags, nflags)) { tsleep(&pmp->trans.sync_wait, PINTERLOCKED, "h2trans2", hz); } } #endif } /* * Start a sub-transaction, there is no 'subdone' function. This will * issue a new modify_tid (mtid) for the current transaction, which is a * CLC (cluster level change) id and not a per-node id. * * This function must be called for each XOP when multiple XOPs are run in * sequence within a transaction. * * Callers typically update the inode with the transaction mtid manually * to enforce sequencing. */ hammer2_tid_t hammer2_trans_sub(hammer2_pfs_t *pmp) { hammer2_tid_t mtid; mtid = atomic_fetchadd_64(&pmp->modify_tid, 1); return (mtid); } void hammer2_trans_setflags(hammer2_pfs_t *pmp, uint32_t flags) { atomic_set_int(&pmp->trans.flags, flags); } /* * Typically used to clear trans flags asynchronously. If TRANS_WAITING * is in the mask, and was previously set, this function will wake up * any waiters. */ void hammer2_trans_clearflags(hammer2_pfs_t *pmp, uint32_t flags) { uint32_t oflags; uint32_t nflags; for (;;) { oflags = pmp->trans.flags; cpu_ccfence(); nflags = oflags & ~flags; if (atomic_cmpset_int(&pmp->trans.flags, oflags, nflags)) { if ((oflags ^ nflags) & HAMMER2_TRANS_WAITING) wakeup(&pmp->trans.sync_wait); break; } cpu_pause(); /* retry */ } } void hammer2_trans_done(hammer2_pfs_t *pmp, uint32_t flags) { uint32_t oflags; uint32_t nflags; #if 0 /* * Modifying ops on the front-end can cause dirty inodes to * build up in the sideq. We don't flush these on inactive/reclaim * due to potential deadlocks, so we have to deal with them from * inside other nominal modifying front-end transactions. */ if ((flags & HAMMER2_TRANS_SIDEQ) && pmp->sideq_count > hammer2_limit_dirty_inodes / 2 && pmp->sideq_count > (pmp->inum_count >> 3) && pmp->mp) { speedup_syncer(pmp->mp); } #endif /* * Clean-up the transaction. Wakeup any waiters when finishing * a flush transaction or transitioning the non-flush transaction * count from 2->1 while a flush transaction is pending. */ for (;;) { oflags = pmp->trans.flags; cpu_ccfence(); KKASSERT(oflags & HAMMER2_TRANS_MASK); nflags = (oflags - 1) & ~flags; if (flags & HAMMER2_TRANS_ISFLUSH) { nflags &= ~HAMMER2_TRANS_WAITING; } if ((oflags & (HAMMER2_TRANS_ISFLUSH|HAMMER2_TRANS_MASK)) == (HAMMER2_TRANS_ISFLUSH|2)) { nflags &= ~HAMMER2_TRANS_WAITING; } if (atomic_cmpset_int(&pmp->trans.flags, oflags, nflags)) { if ((oflags ^ nflags) & HAMMER2_TRANS_WAITING) wakeup(&pmp->trans.sync_wait); break; } cpu_pause(); /* retry */ } } /* * Obtain new, unique inode number (not serialized by caller). */ hammer2_tid_t hammer2_trans_newinum(hammer2_pfs_t *pmp) { hammer2_tid_t tid; tid = atomic_fetchadd_64(&pmp->inode_tid, 1); return tid; } /* * Assert that a strategy call is ok here. Currently we allow strategy * calls in all situations, including during flushes. Previously: * (old) (1) In a normal transaction. */ void hammer2_trans_assert_strategy(hammer2_pfs_t *pmp) { #if 0 KKASSERT((pmp->trans.flags & HAMMER2_TRANS_ISFLUSH) == 0); #endif } /* * Flush the chain and all modified sub-chains through the specified * synchronization point, propagating blockref updates back up. As * part of this propagation, mirror_tid and inode/data usage statistics * propagates back upward. * * Returns a HAMMER2 error code, 0 if no error. Note that I/O errors from * buffers dirtied during the flush operation can occur later. * * modify_tid (clc - cluster level change) is not propagated. * * update_tid (clc) is used for validation and is not propagated by this * function. * * This routine can be called from several places but the most important * is from VFS_SYNC (frontend) via hammer2_xop_inode_flush (backend). * * chain is locked on call and will remain locked on return. The chain's * UPDATE flag indicates that its parent's block table (which is not yet * part of the flush) should be updated. * * flags: * HAMMER2_FLUSH_TOP Indicates that this is the top of the flush. * Is cleared for the recursion. * * HAMMER2_FLUSH_ALL Recurse everything * * HAMMER2_FLUSH_INODE_STOP * Stop at PFS inode or normal inode boundary */ int hammer2_flush(hammer2_chain_t *chain, int flags) { hammer2_flush_info_t info; int loops; /* * Execute the recursive flush and handle deferrals. * * Chains can be ridiculously long (thousands deep), so to * avoid blowing out the kernel stack the recursive flush has a * depth limit. Elements at the limit are placed on a list * for re-execution after the stack has been popped. */ bzero(&info, sizeof(info)); info.flags = flags & ~HAMMER2_FLUSH_TOP; /* * Calculate parent (can be NULL), if not NULL the flush core * expects the parent to be referenced so it can easily lock/unlock * it without it getting ripped up. */ if ((info.parent = chain->parent) != NULL) hammer2_chain_ref(info.parent); /* * Extra ref needed because flush_core expects it when replacing * chain. */ hammer2_chain_ref(chain); loops = 0; for (;;) { /* * [re]flush chain as the deep recursion may have generated * additional modifications. */ if (info.parent != chain->parent) { if (hammer2_debug & 0x0040) { kprintf("LOST CHILD4 %p->%p " "(actual parent %p)\n", info.parent, chain, chain->parent); } hammer2_chain_drop(info.parent); info.parent = chain->parent; hammer2_chain_ref(info.parent); } if (hammer2_flush_core(&info, chain, flags) == 0) break; if (++loops % 1000 == 0) { kprintf("hammer2_flush: excessive loops on %p\n", chain); if (hammer2_debug & 0x100000) Debugger("hell4"); } } #ifdef HAMMER2_SCAN_DEBUG if (info.scan_count >= 10) kprintf("hammer2_flush: scan_count %ld (%ld,%ld,%ld,%ld) " "bt(%ld,%ld,%ld,%ld,%ld,%ld)\n", info.scan_count, info.scan_mod_count, info.scan_upd_count, info.scan_onf_count, info.scan_del_count, info.scan_btype[1], info.scan_btype[2], info.scan_btype[3], info.scan_btype[4], info.scan_btype[5], info.scan_btype[6]); #endif hammer2_chain_drop(chain); if (info.parent) hammer2_chain_drop(info.parent); return (info.error); } /* * This is the core of the chain flushing code. The chain is locked by the * caller and must also have an extra ref on it by the caller, and remains * locked and will have an extra ref on return. info.parent is referenced * but not locked. * * Upon return, the caller can test the UPDATE bit on the chain to determine * if the parent needs updating. * * If non-zero is returned, the chain's parent changed during the flush and * the caller must retry the operation. * * (1) Determine if this node is a candidate for the flush, return if it is * not. fchain and vchain are always candidates for the flush. * * (2) If we recurse too deep the chain is entered onto the deferral list and * the current flush stack is aborted until after the deferral list is * run. * * (3) Recursively flush live children (rbtree). This can create deferrals. * A successful flush clears the MODIFIED and UPDATE bits on the children * and typically causes the parent to be marked MODIFIED as the children * update the parent's block table. A parent might already be marked * MODIFIED due to a deletion (whos blocktable update in the parent is * handled by the frontend), or if the parent itself is modified by the * frontend for other reasons. * * (4) Permanently disconnected sub-trees are cleaned up by the front-end. * Deleted-but-open inodes can still be individually flushed via the * filesystem syncer. * * (5) Delete parents on the way back up if they are normal indirect blocks * and have no children. * * (6) Note that an unmodified child may still need the block table in its * parent updated (e.g. rename/move). The child will have UPDATE set * in this case. * * WARNING ON BREF MODIFY_TID/MIRROR_TID * * blockref.modify_tid is consistent only within a PFS, and will not be * consistent during synchronization. mirror_tid is consistent across the * block device regardless of the PFS. */ static int hammer2_flush_core(hammer2_flush_info_t *info, hammer2_chain_t *chain, int flags) { hammer2_chain_t *parent; hammer2_dev_t *hmp; int save_error; int retry; retry = 0; /* * (1) Optimize downward recursion to locate nodes needing action. * Nothing to do if none of these flags are set. */ if ((chain->flags & HAMMER2_CHAIN_FLUSH_MASK) == 0) return 0; hmp = chain->hmp; /* * NOTE: parent can be NULL, usually due to destroy races. */ parent = info->parent; KKASSERT(chain->parent == parent); /* * Downward search recursion * * We must be careful on cold stops, which often occur on inode * boundaries due to the way hammer2_vfs_sync() sequences the flush. * Be sure to issue an appropriate chain_setflush() */ if ((chain->flags & HAMMER2_CHAIN_PFSBOUNDARY) && (flags & HAMMER2_FLUSH_ALL) == 0 && (flags & HAMMER2_FLUSH_TOP) == 0 && chain->pmp && chain->pmp->mp) { /* * If FLUSH_ALL is not specified the caller does not want * to recurse through PFS roots that have been mounted. * * (If the PFS has not been mounted there may not be * anything monitoring its chains and its up to us * to flush it). * * The typical sequence is to flush dirty PFS's starting at * their root downward, then flush the device root (vchain). * It is this second flush that typically leaves out the * ALL flag. * * However we must still process the PFSROOT chains for block * table updates in their parent (which IS part of our flush). * * NOTE: The volume root, vchain, does not set PFSBOUNDARY. * * NOTE: We must re-set ONFLUSH in the parent to retain if * this chain (that we are skipping) requires work. */ if (chain->flags & (HAMMER2_CHAIN_ONFLUSH | HAMMER2_CHAIN_DESTROY | HAMMER2_CHAIN_MODIFIED)) { hammer2_chain_setflush(parent); } goto done; } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && (flags & HAMMER2_FLUSH_INODE_STOP) && (flags & HAMMER2_FLUSH_ALL) == 0 && (flags & HAMMER2_FLUSH_TOP) == 0 && chain->pmp && chain->pmp->mp) { /* * When FLUSH_INODE_STOP is specified we are being asked not * to include any inode changes for inodes we encounter, * with the exception of the inode that the flush began with. * So: INODE, INODE_STOP, and TOP==0 basically. * * Dirty inodes are flushed based on the hammer2_inode * in-memory structure, issuing a chain_setflush() here * will only cause unnecessary traversals of the topology. */ goto done; #if 0 /* * If FLUSH_INODE_STOP is specified and both ALL and TOP * are clear, we must not flush the chain. The chain should * have already been flushed and any further ONFLUSH/UPDATE * setting will be related to the next flush. * * This features allows us to flush inodes independently of * each other and meta-data above the inodes separately. */ if (chain->flags & (HAMMER2_CHAIN_ONFLUSH | HAMMER2_CHAIN_DESTROY | HAMMER2_CHAIN_MODIFIED)) { if (parent) hammer2_chain_setflush(parent); } #endif } else if (info->depth == HAMMER2_FLUSH_DEPTH_LIMIT) { /* * Recursion depth reached. */ panic("hammer2: flush depth limit"); } else if (chain->flags & (HAMMER2_CHAIN_ONFLUSH | HAMMER2_CHAIN_DESTROY)) { /* * Downward recursion search (actual flush occurs bottom-up). * pre-clear ONFLUSH. It can get set again due to races or * flush errors, which we want so the scan finds us again in * the next flush. * * We must also recurse if DESTROY is set so we can finally * get rid of the related children, otherwise the node will * just get re-flushed on lastdrop. * * WARNING! The recursion will unlock/relock info->parent * (which is 'chain'), potentially allowing it * to be ripped up. */ atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONFLUSH); save_error = info->error; info->error = 0; info->parent = chain; /* * We may have to do this twice to catch any indirect * block maintenance that occurs. */ hammer2_spin_ex(&chain->core.spin); RB_SCAN(hammer2_chain_tree, &chain->core.rbtree, NULL, hammer2_flush_recurse, info); if (chain->flags & HAMMER2_CHAIN_ONFLUSH) { atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONFLUSH); RB_SCAN(hammer2_chain_tree, &chain->core.rbtree, NULL, hammer2_flush_recurse, info); } hammer2_spin_unex(&chain->core.spin); info->parent = parent; /* * Re-set the flush bits if the flush was incomplete or * an error occurred. If an error occurs it is typically * an allocation error. Errors do not cause deferrals. */ if (info->error) hammer2_chain_setflush(chain); info->error |= save_error; /* * If we lost the parent->chain association we have to * stop processing this chain because it is no longer * in this recursion. If it moved, it will be handled * by the ONFLUSH flag elsewhere. */ if (chain->parent != parent) { kprintf("LOST CHILD2 %p->%p (actual parent %p)\n", parent, chain, chain->parent); goto done; } } /* * Now we are in the bottom-up part of the recursion. * * We continue to try to update the chain on lower-level errors, but * the flush code may decide not to flush the volume root. * * XXX should we continue to try to update the chain if an error * occurred? */ /* * Both parent and chain must be locked in order to flush chain, * in order to properly update the parent under certain conditions. * * In addition, we can't safely unlock/relock the chain once we * start flushing the chain itself, which we would have to do later * on in order to lock the parent if we didn't do that now. */ hammer2_chain_ref_hold(chain); hammer2_chain_unlock(chain); if (parent) hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS); hammer2_chain_lock(chain, HAMMER2_RESOLVE_MAYBE); hammer2_chain_drop_unhold(chain); /* * Can't process if we can't access their content. */ if ((parent && parent->error) || chain->error) { kprintf("hammer2: chain error during flush\n"); info->error |= chain->error; if (parent) { info->error |= parent->error; hammer2_chain_unlock(parent); } goto done; } if (chain->parent != parent) { if (hammer2_debug & 0x0040) { kprintf("LOST CHILD3 %p->%p (actual parent %p)\n", parent, chain, chain->parent); } KKASSERT(parent != NULL); hammer2_chain_unlock(parent); retry = 1; goto done; } /* * Propagate the DESTROY flag downwards. This dummies up the flush * code and tries to invalidate related buffer cache buffers to * avoid the disk write. */ if (parent && (parent->flags & HAMMER2_CHAIN_DESTROY)) atomic_set_int(&chain->flags, HAMMER2_CHAIN_DESTROY); /* * Dispose of the modified bit. * * If parent is present, the UPDATE bit should already be set. * UPDATE should already be set. * bref.mirror_tid should already be set. */ if (chain->flags & HAMMER2_CHAIN_MODIFIED) { KKASSERT((chain->flags & HAMMER2_CHAIN_UPDATE) || chain->parent == NULL); atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); atomic_add_long(&hammer2_count_modified_chains, -1); /* * Manage threads waiting for excessive dirty memory to * be retired. */ if (chain->pmp) hammer2_pfs_memory_wakeup(chain->pmp, -1); #if 0 if ((chain->flags & HAMMER2_CHAIN_UPDATE) == 0 && chain != &hmp->vchain && chain != &hmp->fchain) { /* * Set UPDATE bit indicating that the parent block * table requires updating. */ atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE); } #endif /* * Issue the flush. This is indirect via the DIO. * * NOTE: A DELETED node that reaches this point must be * flushed for synchronization point consistency. * * NOTE: Even though MODIFIED was already set, the related DIO * might not be dirty due to a system buffer cache * flush and must be set dirty if we are going to make * further modifications to the buffer. Chains with * embedded data don't need this. */ if (hammer2_debug & 0x1000) { kprintf("Flush %p.%d %016jx/%d data=%016jx\n", chain, chain->bref.type, (uintmax_t)chain->bref.key, chain->bref.keybits, (uintmax_t)chain->bref.data_off); } /* * Update chain CRCs for flush. * * NOTE: Volume headers are NOT flushed here as they require * special processing. */ switch(chain->bref.type) { case HAMMER2_BREF_TYPE_FREEMAP: /* * Update the volume header's freemap_tid to the * freemap's flushing mirror_tid. * * (note: embedded data, do not call setdirty) */ KKASSERT(hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED); KKASSERT(chain == &hmp->fchain); hmp->voldata.freemap_tid = chain->bref.mirror_tid; if (hammer2_debug & 0x8000) { /* debug only, avoid syslogd loop */ kprintf("sync freemap mirror_tid %08jx\n", (intmax_t)chain->bref.mirror_tid); } /* * The freemap can be flushed independently of the * main topology, but for the case where it is * flushed in the same transaction, and flushed * before vchain (a case we want to allow for * performance reasons), make sure modifications * made during the flush under vchain use a new * transaction id. * * Otherwise the mount recovery code will get confused. */ ++hmp->voldata.mirror_tid; break; case HAMMER2_BREF_TYPE_VOLUME: /* * The free block table is flushed by * hammer2_vfs_sync() before it flushes vchain. * We must still hold fchain locked while copying * voldata to volsync, however. * * These do not error per-say since their data does * not need to be re-read from media on lock. * * (note: embedded data, do not call setdirty) */ hammer2_chain_lock(&hmp->fchain, HAMMER2_RESOLVE_ALWAYS); hammer2_voldata_lock(hmp); if (hammer2_debug & 0x8000) { /* debug only, avoid syslogd loop */ kprintf("sync volume mirror_tid %08jx\n", (intmax_t)chain->bref.mirror_tid); } /* * Update the volume header's mirror_tid to the * main topology's flushing mirror_tid. It is * possible that voldata.mirror_tid is already * beyond bref.mirror_tid due to the bump we made * above in BREF_TYPE_FREEMAP. */ if (hmp->voldata.mirror_tid < chain->bref.mirror_tid) { hmp->voldata.mirror_tid = chain->bref.mirror_tid; } /* * The volume header is flushed manually by the * syncer, not here. All we do here is adjust the * crc's. */ KKASSERT(chain->data != NULL); KKASSERT(chain->dio == NULL); hmp->voldata.icrc_sects[HAMMER2_VOL_ICRC_SECT1]= hammer2_icrc32( (char *)&hmp->voldata + HAMMER2_VOLUME_ICRC1_OFF, HAMMER2_VOLUME_ICRC1_SIZE); hmp->voldata.icrc_sects[HAMMER2_VOL_ICRC_SECT0]= hammer2_icrc32( (char *)&hmp->voldata + HAMMER2_VOLUME_ICRC0_OFF, HAMMER2_VOLUME_ICRC0_SIZE); hmp->voldata.icrc_volheader = hammer2_icrc32( (char *)&hmp->voldata + HAMMER2_VOLUME_ICRCVH_OFF, HAMMER2_VOLUME_ICRCVH_SIZE); if (hammer2_debug & 0x8000) { /* debug only, avoid syslogd loop */ kprintf("syncvolhdr %016jx %016jx\n", hmp->voldata.mirror_tid, hmp->vchain.bref.mirror_tid); } hmp->volsync = hmp->voldata; atomic_set_int(&chain->flags, HAMMER2_CHAIN_VOLUMESYNC); hammer2_voldata_unlock(hmp); hammer2_chain_unlock(&hmp->fchain); break; case HAMMER2_BREF_TYPE_DATA: /* * Data elements have already been flushed via the * logical file buffer cache. Their hash was set in * the bref by the vop_write code. Do not re-dirty. * * Make sure any device buffer(s) have been flushed * out here (there aren't usually any to flush) XXX. */ break; case HAMMER2_BREF_TYPE_INDIRECT: case HAMMER2_BREF_TYPE_FREEMAP_NODE: case HAMMER2_BREF_TYPE_FREEMAP_LEAF: /* * Buffer I/O will be cleaned up when the volume is * flushed (but the kernel is free to flush it before * then, as well). */ hammer2_chain_setcheck(chain, chain->data); break; case HAMMER2_BREF_TYPE_DIRENT: /* * A directory entry can use the check area to store * the filename for filenames <= 64 bytes, don't blow * it up! */ if (chain->bytes) hammer2_chain_setcheck(chain, chain->data); break; case HAMMER2_BREF_TYPE_INODE: /* * NOTE: We must call io_setdirty() to make any late * changes to the inode data, the system might * have already flushed the buffer. */ if (chain->data->ipdata.meta.op_flags & HAMMER2_OPFLAG_PFSROOT) { /* * non-NULL pmp if mounted as a PFS. We must * sync fields cached in the pmp? XXX */ hammer2_inode_data_t *ipdata; hammer2_io_setdirty(chain->dio); ipdata = &chain->data->ipdata; if (chain->pmp) { ipdata->meta.pfs_inum = chain->pmp->inode_tid; } } else { /* can't be mounted as a PFS */ } hammer2_chain_setcheck(chain, chain->data); break; default: panic("hammer2_flush_core: unsupported " "embedded bref %d", chain->bref.type); /* NOT REACHED */ } /* * If the chain was destroyed try to avoid unnecessary I/O * that might not have yet occurred. Remove the data range * from dedup candidacy and attempt to invalidation that * potentially dirty portion of the I/O buffer. */ if (chain->flags & HAMMER2_CHAIN_DESTROY) { hammer2_io_dedup_delete(hmp, chain->bref.type, chain->bref.data_off, chain->bytes); #if 0 hammer2_io_t *dio; if (chain->dio) { hammer2_io_inval(chain->dio, chain->bref.data_off, chain->bytes); } else if ((dio = hammer2_io_getquick(hmp, chain->bref.data_off, chain->bytes, 1)) != NULL) { hammer2_io_inval(dio, chain->bref.data_off, chain->bytes); hammer2_io_putblk(&dio); } #endif } } /* * If UPDATE is set the parent block table may need to be updated. * This can fail if the hammer2_chain_modify() fails. * * NOTE: UPDATE may be set on vchain or fchain in which case * parent could be NULL, or on an inode that has not yet * been inserted into the radix tree. It's easiest to allow * the case and test for NULL. parent can also wind up being * NULL due to a deletion so we need to handle the case anyway. * * NOTE: UPDATE can be set when chains are renamed into or out of * an indirect block, without the chain itself being flagged * MODIFIED. * * If no parent exists we can just clear the UPDATE bit. If the * chain gets reattached later on the bit will simply get set * again. */ if ((chain->flags & HAMMER2_CHAIN_UPDATE) && parent == NULL) atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE); /* * When flushing an inode outside of a FLUSH_FSSYNC we must NOT * update the parent block table to point at the flushed inode. * The block table should only ever be updated by the filesystem * sync code. If we do, inode<->inode dependencies (such as * directory entries vs inode nlink count) can wind up not being * flushed together and result in a broken topology if a crash/reboot * occurs at the wrong time. */ if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && (flags & HAMMER2_FLUSH_INODE_STOP) && (flags & HAMMER2_FLUSH_FSSYNC) == 0 && (flags & HAMMER2_FLUSH_ALL) == 0 && chain->pmp && chain->pmp->mp) { #ifdef HAMMER2_DEBUG_SYNC kprintf("inum %ld do not update parent, non-fssync\n", (long)chain->bref.key); #endif goto skipupdate; } #ifdef HAMMER2_DEBUG_SYNC if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) kprintf("inum %ld update parent\n", (long)chain->bref.key); #endif /* * The chain may need its blockrefs updated in the parent, normal * path. */ if (chain->flags & HAMMER2_CHAIN_UPDATE) { hammer2_blockref_t *base; int count; /* * Clear UPDATE flag, mark parent modified, update its * modify_tid if necessary, and adjust the parent blockmap. */ atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE); /* * (optional code) * * Avoid actually modifying and updating the parent if it * was flagged for destruction. This can greatly reduce * disk I/O in large tree removals because the * hammer2_io_setinval() call in the upward recursion * (see MODIFIED code above) can only handle a few cases. */ if (parent->flags & HAMMER2_CHAIN_DESTROY) { if (parent->bref.modify_tid < chain->bref.modify_tid) { parent->bref.modify_tid = chain->bref.modify_tid; } atomic_clear_int(&chain->flags, HAMMER2_CHAIN_BLKMAPPED | HAMMER2_CHAIN_BLKMAPUPD); goto skipupdate; } /* * The flusher is responsible for deleting empty indirect * blocks at this point. If we don't do this, no major harm * will be done but the empty indirect blocks will stay in * the topology and make it a messy and inefficient. * * The flusher is also responsible for collapsing the * content of an indirect block into its parent whenever * possible (with some hysteresis). Not doing this will also * not harm the topology, but would make it messy and * inefficient. */ if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT) { if (hammer2_chain_indirect_maintenance(parent, chain)) goto skipupdate; } /* * We are updating the parent's blockmap, the parent must * be set modified. If this fails we re-set the UPDATE flag * in the child. * * NOTE! A modification error can be ENOSPC. We still want * to flush modified chains recursively, not break out, * so we just skip the update in this situation and * continue. That is, we still need to try to clean * out dirty chains and buffers. * * This may not help bulkfree though. XXX */ save_error = hammer2_chain_modify(parent, 0, 0, 0); if (save_error) { info->error |= save_error; kprintf("hammer2_flush: %016jx.%02x error=%08x\n", parent->bref.data_off, parent->bref.type, save_error); atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE); goto skipupdate; } if (parent->bref.modify_tid < chain->bref.modify_tid) parent->bref.modify_tid = chain->bref.modify_tid; /* * Calculate blockmap pointer */ switch(parent->bref.type) { case HAMMER2_BREF_TYPE_INODE: /* * Access the inode's block array. However, there is * no block array if the inode is flagged DIRECTDATA. */ if (parent->data && (parent->data->ipdata.meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA) == 0) { base = &parent->data-> ipdata.u.blockset.blockref[0]; } else { base = NULL; } count = HAMMER2_SET_COUNT; break; case HAMMER2_BREF_TYPE_INDIRECT: case HAMMER2_BREF_TYPE_FREEMAP_NODE: if (parent->data) base = &parent->data->npdata[0]; else base = NULL; count = parent->bytes / sizeof(hammer2_blockref_t); break; case HAMMER2_BREF_TYPE_VOLUME: base = &chain->hmp->voldata.sroot_blockset.blockref[0]; count = HAMMER2_SET_COUNT; break; case HAMMER2_BREF_TYPE_FREEMAP: base = &parent->data->npdata[0]; count = HAMMER2_SET_COUNT; break; default: base = NULL; count = 0; panic("hammer2_flush_core: " "unrecognized blockref type: %d", parent->bref.type); break; } /* * Blocktable updates */ if (base && (chain->flags & HAMMER2_CHAIN_BLKMAPUPD)) { if (chain->flags & HAMMER2_CHAIN_BLKMAPPED) { hammer2_spin_ex(&parent->core.spin); hammer2_base_delete(parent, base, count, chain, NULL); hammer2_spin_unex(&parent->core.spin); /* base_delete clears both bits */ } else { atomic_clear_int(&chain->flags, HAMMER2_CHAIN_BLKMAPUPD); } } if (base && (chain->flags & HAMMER2_CHAIN_BLKMAPPED) == 0) { hammer2_spin_ex(&parent->core.spin); hammer2_base_insert(parent, base, count, chain, &chain->bref); hammer2_spin_unex(&parent->core.spin); /* base_insert sets BLKMAPPED */ } } skipupdate: if (parent) hammer2_chain_unlock(parent); /* * Final cleanup after flush */ done: KKASSERT(chain->refs > 0); return retry; } /* * Flush recursion helper, called from flush_core, calls flush_core. * * Flushes the children of the caller's chain (info->parent), restricted * by sync_tid. * * This function may set info->error as a side effect. * * WARNING! If we do not call hammer2_flush_core() we must update * bref.mirror_tid ourselves to indicate that the flush has * processed the child. * * WARNING! parent->core spinlock is held on entry and return. */ static int hammer2_flush_recurse(hammer2_chain_t *child, void *data) { hammer2_flush_info_t *info = data; hammer2_chain_t *parent = info->parent; #ifdef HAMMER2_SCAN_DEBUG ++info->scan_count; if (child->flags & HAMMER2_CHAIN_MODIFIED) ++info->scan_mod_count; if (child->flags & HAMMER2_CHAIN_UPDATE) ++info->scan_upd_count; if (child->flags & HAMMER2_CHAIN_ONFLUSH) ++info->scan_onf_count; #endif /* * (child can never be fchain or vchain so a special check isn't * needed). * * We must ref the child before unlocking the spinlock. * * The caller has added a ref to the parent so we can temporarily * unlock it in order to lock the child. However, if it no longer * winds up being the child of the parent we must skip this child. * * NOTE! chain locking errors are fatal. They are never out-of-space * errors. */ hammer2_chain_ref(child); hammer2_spin_unex(&parent->core.spin); hammer2_chain_ref_hold(parent); hammer2_chain_unlock(parent); hammer2_chain_lock(child, HAMMER2_RESOLVE_MAYBE); if (child->parent != parent) { kprintf("LOST CHILD1 %p->%p (actual parent %p)\n", parent, child, child->parent); goto done; } if (child->error) { kprintf("CHILD ERROR DURING FLUSH LOCK %p->%p\n", parent, child); info->error |= child->error; goto done; } /* * Must propagate the DESTROY flag downwards, otherwise the * parent could end up never being removed because it will * be requeued to the flusher if it survives this run due to * the flag. */ if (parent && (parent->flags & HAMMER2_CHAIN_DESTROY)) atomic_set_int(&child->flags, HAMMER2_CHAIN_DESTROY); #ifdef HAMMER2_SCAN_DEBUG if (child->flags & HAMMER2_CHAIN_DESTROY) ++info->scan_del_count; #endif /* * Special handling of the root inode. Because the root inode * contains an index of all the inodes in the PFS in addition to * its normal directory entries, any flush that is not part of a * filesystem sync must only flush the directory entries, and not * anything else. * * The child might be an indirect block, but H2 guarantees that * the key-range will fully partition the inode index from the * directory entries so the case just works naturally. */ if ((parent->bref.flags & HAMMER2_BREF_FLAG_PFSROOT) && (child->flags & HAMMER2_CHAIN_DESTROY) == 0 && parent->bref.type == HAMMER2_BREF_TYPE_INODE && (info->flags & HAMMER2_FLUSH_FSSYNC) == 0) { if ((child->bref.key & HAMMER2_DIRHASH_VISIBLE) == 0) { if (child->flags & HAMMER2_CHAIN_FLUSH_MASK) { hammer2_chain_setflush(parent); } goto done; } } /* * Recurse and collect deferral data. We're in the media flush, * this can cross PFS boundaries. */ if (child->flags & HAMMER2_CHAIN_FLUSH_MASK) { #ifdef HAMMER2_SCAN_DEBUG if (child->bref.type < 7) ++info->scan_btype[child->bref.type]; #endif ++info->depth; hammer2_flush_core(info, child, info->flags); --info->depth; } done: /* * Relock to continue the loop. */ hammer2_chain_unlock(child); hammer2_chain_lock(parent, HAMMER2_RESOLVE_MAYBE); hammer2_chain_drop_unhold(parent); if (parent->error) { kprintf("PARENT ERROR DURING FLUSH LOCK %p->%p\n", parent, child); info->error |= parent->error; } hammer2_chain_drop(child); KKASSERT(info->parent == parent); hammer2_spin_ex(&parent->core.spin); return (0); } /* * flush helper (backend threaded) * * Flushes chain topology for the specified inode. * * HAMMER2_XOP_INODE_STOP The flush recursion stops at inode boundaries. * Inodes belonging to the same flush are flushed * separately. * * chain->parent can be NULL, usually due to destroy races or detached inodes. * * Primarily called from vfs_sync(). */ void hammer2_xop_inode_flush(hammer2_xop_t *arg, void *scratch __unused, int clindex) { hammer2_xop_flush_t *xop = &arg->xop_flush; hammer2_chain_t *chain; hammer2_inode_t *ip; hammer2_dev_t *hmp; hammer2_pfs_t *pmp; hammer2_devvp_t *e; struct m_vnode *devvp; int flush_error = 0; int fsync_error = 0; int total_error = 0; int j; int xflags; int ispfsroot = 0; xflags = HAMMER2_FLUSH_TOP; if (xop->head.flags & HAMMER2_XOP_INODE_STOP) xflags |= HAMMER2_FLUSH_INODE_STOP; if (xop->head.flags & HAMMER2_XOP_FSSYNC) xflags |= HAMMER2_FLUSH_FSSYNC; /* * Flush core chains */ ip = xop->head.ip1; pmp = ip->pmp; chain = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); if (chain) { hmp = chain->hmp; if (chain->flags & HAMMER2_CHAIN_FLUSH_MASK) { /* * Due to flush partitioning the chain topology * above the inode's chain may no longer be flagged. * When asked to flush an inode, remark the topology * leading to that inode. */ if (chain->parent) hammer2_chain_setflush(chain->parent); hammer2_flush(chain, xflags); /* XXX cluster */ if (ip == pmp->iroot && pmp != hmp->spmp) { hammer2_spin_ex(&pmp->blockset_spin); pmp->pfs_iroot_blocksets[clindex] = chain->data->ipdata.u.blockset; hammer2_spin_unex(&pmp->blockset_spin); } #if 0 /* * Propogate upwards but only cross an inode boundary * for inodes associated with the current filesystem * sync. */ if ((xop->head.flags & HAMMER2_XOP_PARENTONFLUSH) || chain->bref.type != HAMMER2_BREF_TYPE_INODE) { parent = chain->parent; if (parent) hammer2_chain_setflush(parent); } #endif } if (chain->flags & HAMMER2_CHAIN_PFSBOUNDARY) ispfsroot = 1; hammer2_chain_unlock(chain); hammer2_chain_drop(chain); chain = NULL; } else { hmp = NULL; } /* * Only flush the volume header if asked to, plus the inode must also * be the PFS root. */ if ((xop->head.flags & HAMMER2_XOP_VOLHDR) == 0) goto skip; if (ispfsroot == 0) goto skip; /* * Flush volume roots. Avoid replication, we only want to * flush each hammer2_dev (hmp) once. */ for (j = clindex - 1; j >= 0; --j) { if ((chain = ip->cluster.array[j].chain) != NULL) { if (chain->hmp == hmp) { chain = NULL; /* safety */ goto skip; } } } chain = NULL; /* safety */ /* * spmp transaction. The super-root is never directly mounted so * there shouldn't be any vnodes, let alone any dirty vnodes * associated with it, so we shouldn't have to mess around with any * vnode flushes here. */ hammer2_trans_init(hmp->spmp, HAMMER2_TRANS_ISFLUSH); /* * We must flush the superroot down to the PFS iroot. Remember * that hammer2_chain_setflush() stops at inode boundaries, so * the pmp->iroot has been flushed and flagged down to the superroot, * but the volume root (vchain) probably has not yet been flagged. */ if (hmp->spmp->iroot) { chain = hmp->spmp->iroot->cluster.array[0].chain; if (chain) { hammer2_chain_ref(chain); hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS); flush_error |= hammer2_flush(chain, HAMMER2_FLUSH_TOP | HAMMER2_FLUSH_INODE_STOP | HAMMER2_FLUSH_FSSYNC); hammer2_chain_unlock(chain); hammer2_chain_drop(chain); } } /* * Media mounts have two 'roots', vchain for the topology * and fchain for the free block table. Flush both. * * Note that the topology and free block table are handled * independently, so the free block table can wind up being * ahead of the topology. We depend on the bulk free scan * code to deal with any loose ends. * * vchain and fchain do not error on-lock since their data does * not have to be re-read from media. */ hammer2_chain_ref(&hmp->vchain); hammer2_chain_lock(&hmp->vchain, HAMMER2_RESOLVE_ALWAYS); hammer2_chain_ref(&hmp->fchain); hammer2_chain_lock(&hmp->fchain, HAMMER2_RESOLVE_ALWAYS); if (hmp->fchain.flags & HAMMER2_CHAIN_FLUSH_MASK) { /* * This will also modify vchain as a side effect, * mark vchain as modified now. */ hammer2_voldata_modify(hmp); chain = &hmp->fchain; flush_error |= hammer2_flush(chain, HAMMER2_FLUSH_TOP); KKASSERT(chain == &hmp->fchain); } hammer2_chain_unlock(&hmp->fchain); hammer2_chain_unlock(&hmp->vchain); hammer2_chain_drop(&hmp->fchain); /* vchain dropped down below */ hammer2_chain_lock(&hmp->vchain, HAMMER2_RESOLVE_ALWAYS); if (hmp->vchain.flags & HAMMER2_CHAIN_FLUSH_MASK) { chain = &hmp->vchain; flush_error |= hammer2_flush(chain, HAMMER2_FLUSH_TOP); KKASSERT(chain == &hmp->vchain); } hammer2_chain_unlock(&hmp->vchain); hammer2_chain_drop(&hmp->vchain); /* * We can't safely flush the volume header until we have * flushed any device buffers which have built up. * * XXX this isn't being incremental */ TAILQ_FOREACH(e, &hmp->devvpl, entry) { devvp = e->devvp; KKASSERT(devvp); vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); fsync_error = VOP_FSYNC(devvp, MNT_WAIT, 0); vn_unlock(devvp); if (fsync_error || flush_error) { kprintf("hammer2: sync error fsync=%d h2flush=0x%04x dev=%s\n", fsync_error, flush_error, e->path); } } /* * The flush code sets CHAIN_VOLUMESYNC to indicate that the * volume header needs synchronization via hmp->volsync. * * XXX synchronize the flag & data with only this flush XXX */ if (fsync_error == 0 && flush_error == 0 && (hmp->vchain.flags & HAMMER2_CHAIN_VOLUMESYNC)) { struct m_buf *bp; int vol_error = 0; /* * Synchronize the disk before flushing the volume * header. */ /* bp = getpbuf(NULL); bp->b_bio1.bio_offset = 0; bp->b_bufsize = 0; bp->b_bcount = 0; bp->b_cmd = BUF_CMD_FLUSH; bp->b_bio1.bio_done = biodone_sync; bp->b_bio1.bio_flags |= BIO_SYNC; vn_strategy(hmp->devvp, &bp->b_bio1); fsync_error = biowait(&bp->b_bio1, "h2vol"); relpbuf(bp, NULL); */ /* * Then we can safely flush the version of the * volume header synchronized by the flush code. */ j = hmp->volhdrno + 1; if (j < 0) j = 0; if (j >= HAMMER2_NUM_VOLHDRS) j = 0; if (j * HAMMER2_ZONE_BYTES64 + HAMMER2_SEGSIZE > hmp->volsync.volu_size) { j = 0; } if (hammer2_debug & 0x8000) { /* debug only, avoid syslogd loop */ kprintf("sync volhdr %d %jd\n", j, (intmax_t)hmp->volsync.volu_size); } bp = getblkx(hmp->devvp, j * HAMMER2_ZONE_BYTES64, HAMMER2_VOLUME_BYTES, GETBLK_KVABIO, 0); atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_VOLUMESYNC); bkvasync(bp); bcopy(&hmp->volsync, bp->b_data, HAMMER2_VOLUME_BYTES); vol_error = bwrite(bp); hmp->volhdrno = j; if (vol_error) fsync_error = vol_error; } if (flush_error) total_error = flush_error; if (fsync_error) total_error = hammer2_errno_to_error(fsync_error); /* spmp trans */ hammer2_trans_done(hmp->spmp, HAMMER2_TRANS_ISFLUSH); skip: hammer2_xop_feed(&xop->head, NULL, clindex, total_error); }
