/* -*- mode: c; c-basic-offset: 8; -*- * vim: noexpandtab sw=8 ts=8 sts=0: * * localalloc.c * * Node local data allocation * * Copyright (C) 2002, 2004 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include #include #include #include #include #include #include "ocfs2.h" #include "alloc.h" #include "blockcheck.h" #include "dlmglue.h" #include "inode.h" #include "journal.h" #include "localalloc.h" #include "suballoc.h" #include "super.h" #include "sysfile.h" #include "ocfs2_trace.h" #include "buffer_head_io.h" #define OCFS2_LOCAL_ALLOC(dinode) (&((dinode)->id2.i_lab)) static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc); static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb, struct ocfs2_dinode *alloc, u32 *numbits, struct ocfs2_alloc_reservation *resv); static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc); static int ocfs2_sync_local_to_main(struct ocfs2_super *osb, handle_t *handle, struct ocfs2_dinode *alloc, struct inode *main_bm_inode, struct buffer_head *main_bm_bh); static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb, struct ocfs2_alloc_context **ac, struct inode **bitmap_inode, struct buffer_head **bitmap_bh); static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb, handle_t *handle, struct ocfs2_alloc_context *ac); static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb, struct inode *local_alloc_inode); /* * ocfs2_la_default_mb() - determine a default size, in megabytes of * the local alloc. * * Generally, we'd like to pick as large a local alloc as * possible. Performance on large workloads tends to scale * proportionally to la size. In addition to that, the reservations * code functions more efficiently as it can reserve more windows for * write. * * Some things work against us when trying to choose a large local alloc: * * - We need to ensure our sizing is picked to leave enough space in * group descriptors for other allocations (such as block groups, * etc). Picking default sizes which are a multiple of 4 could help * - block groups are allocated in 2mb and 4mb chunks. * * - Likewise, we don't want to starve other nodes of bits on small * file systems. This can easily be taken care of by limiting our * default to a reasonable size (256M) on larger cluster sizes. * * - Some file systems can't support very large sizes - 4k and 8k in * particular are limited to less than 128 and 256 megabytes respectively. * * The following reference table shows group descriptor and local * alloc maximums at various cluster sizes (4k blocksize) * * csize: 4K group: 126M la: 121M * csize: 8K group: 252M la: 243M * csize: 16K group: 504M la: 486M * csize: 32K group: 1008M la: 972M * csize: 64K group: 2016M la: 1944M * csize: 128K group: 4032M la: 3888M * csize: 256K group: 8064M la: 7776M * csize: 512K group: 16128M la: 15552M * csize: 1024K group: 32256M la: 31104M */ #define OCFS2_LA_MAX_DEFAULT_MB 256 #define OCFS2_LA_OLD_DEFAULT 8 unsigned int ocfs2_la_default_mb(struct ocfs2_super *osb) { unsigned int la_mb; unsigned int gd_mb; unsigned int la_max_mb; unsigned int megs_per_slot; struct super_block *sb = osb->sb; gd_mb = ocfs2_clusters_to_megabytes(osb->sb, 8 * ocfs2_group_bitmap_size(sb, 0, osb->s_feature_incompat)); /* * This takes care of files systems with very small group * descriptors - 512 byte blocksize at cluster sizes lower * than 16K and also 1k blocksize with 4k cluster size. */ if ((sb->s_blocksize == 512 && osb->s_clustersize <= 8192) || (sb->s_blocksize == 1024 && osb->s_clustersize == 4096)) return OCFS2_LA_OLD_DEFAULT; /* * Leave enough room for some block groups and make the final * value we work from a multiple of 4. */ gd_mb -= 16; gd_mb &= 0xFFFFFFFB; la_mb = gd_mb; /* * Keep window sizes down to a reasonable default */ if (la_mb > OCFS2_LA_MAX_DEFAULT_MB) { /* * Some clustersize / blocksize combinations will have * given us a larger than OCFS2_LA_MAX_DEFAULT_MB * default size, but get poor distribution when * limited to exactly 256 megabytes. * * As an example, 16K clustersize at 4K blocksize * gives us a cluster group size of 504M. Paring the * local alloc size down to 256 however, would give us * only one window and around 200MB left in the * cluster group. Instead, find the first size below * 256 which would give us an even distribution. * * Larger cluster group sizes actually work out pretty * well when pared to 256, so we don't have to do this * for any group that fits more than two * OCFS2_LA_MAX_DEFAULT_MB windows. */ if (gd_mb > (2 * OCFS2_LA_MAX_DEFAULT_MB)) la_mb = 256; else { unsigned int gd_mult = gd_mb; while (gd_mult > 256) gd_mult = gd_mult >> 1; la_mb = gd_mult; } } megs_per_slot = osb->osb_clusters_at_boot / osb->max_slots; megs_per_slot = ocfs2_clusters_to_megabytes(osb->sb, megs_per_slot); /* Too many nodes, too few disk clusters. */ if (megs_per_slot < la_mb) la_mb = megs_per_slot; /* We can't store more bits than we can in a block. */ la_max_mb = ocfs2_clusters_to_megabytes(osb->sb, ocfs2_local_alloc_size(sb) * 8); if (la_mb > la_max_mb) la_mb = la_max_mb; return la_mb; } void ocfs2_la_set_sizes(struct ocfs2_super *osb, int requested_mb) { struct super_block *sb = osb->sb; unsigned int la_default_mb = ocfs2_la_default_mb(osb); unsigned int la_max_mb; la_max_mb = ocfs2_clusters_to_megabytes(sb, ocfs2_local_alloc_size(sb) * 8); trace_ocfs2_la_set_sizes(requested_mb, la_max_mb, la_default_mb); if (requested_mb == -1) { /* No user request - use defaults */ osb->local_alloc_default_bits = ocfs2_megabytes_to_clusters(sb, la_default_mb); } else if (requested_mb > la_max_mb) { /* Request is too big, we give the maximum available */ osb->local_alloc_default_bits = ocfs2_megabytes_to_clusters(sb, la_max_mb); } else { osb->local_alloc_default_bits = ocfs2_megabytes_to_clusters(sb, requested_mb); } osb->local_alloc_bits = osb->local_alloc_default_bits; } static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb) { return (osb->local_alloc_state == OCFS2_LA_THROTTLED || osb->local_alloc_state == OCFS2_LA_ENABLED); } void ocfs2_local_alloc_seen_free_bits(struct ocfs2_super *osb, unsigned int num_clusters) { spin_lock(&osb->osb_lock); if (osb->local_alloc_state == OCFS2_LA_DISABLED || osb->local_alloc_state == OCFS2_LA_THROTTLED) if (num_clusters >= osb->local_alloc_default_bits) { cancel_delayed_work(&osb->la_enable_wq); osb->local_alloc_state = OCFS2_LA_ENABLED; } spin_unlock(&osb->osb_lock); } void ocfs2_la_enable_worker(struct work_struct *work) { struct ocfs2_super *osb = container_of(work, struct ocfs2_super, la_enable_wq.work); spin_lock(&osb->osb_lock); osb->local_alloc_state = OCFS2_LA_ENABLED; spin_unlock(&osb->osb_lock); } /* * Tell us whether a given allocation should use the local alloc * file. Otherwise, it has to go to the main bitmap. * * This function does semi-dirty reads of local alloc size and state! * This is ok however, as the values are re-checked once under mutex. */ int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits) { int ret = 0; int la_bits; spin_lock(&osb->osb_lock); la_bits = osb->local_alloc_bits; if (!ocfs2_la_state_enabled(osb)) goto bail; /* la_bits should be at least twice the size (in clusters) of * a new block group. We want to be sure block group * allocations go through the local alloc, so allow an * allocation to take up to half the bitmap. */ if (bits > (la_bits / 2)) goto bail; ret = 1; bail: trace_ocfs2_alloc_should_use_local( (unsigned long long)bits, osb->local_alloc_state, la_bits, ret); spin_unlock(&osb->osb_lock); return ret; } int ocfs2_load_local_alloc(struct ocfs2_super *osb) { int status = 0; struct ocfs2_dinode *alloc = NULL; struct buffer_head *alloc_bh = NULL; u32 num_used; struct inode *inode = NULL; struct ocfs2_local_alloc *la; if (osb->local_alloc_bits == 0) goto bail; if (osb->local_alloc_bits >= osb->bitmap_cpg) { mlog(ML_NOTICE, "Requested local alloc window %d is larger " "than max possible %u. Using defaults.\n", osb->local_alloc_bits, (osb->bitmap_cpg - 1)); osb->local_alloc_bits = ocfs2_megabytes_to_clusters(osb->sb, ocfs2_la_default_mb(osb)); } /* read the alloc off disk */ inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE, osb->slot_num); if (!inode) { status = -EINVAL; mlog_errno(status); goto bail; } status = ocfs2_read_inode_block_full(inode, &alloc_bh, OCFS2_BH_IGNORE_CACHE); if (status < 0) { mlog_errno(status); goto bail; } alloc = (struct ocfs2_dinode *) alloc_bh->b_data; la = OCFS2_LOCAL_ALLOC(alloc); if (!(le32_to_cpu(alloc->i_flags) & (OCFS2_LOCAL_ALLOC_FL|OCFS2_BITMAP_FL))) { mlog(ML_ERROR, "Invalid local alloc inode, %llu\n", (unsigned long long)OCFS2_I(inode)->ip_blkno); status = -EINVAL; goto bail; } if ((la->la_size == 0) || (le16_to_cpu(la->la_size) > ocfs2_local_alloc_size(inode->i_sb))) { mlog(ML_ERROR, "Local alloc size is invalid (la_size = %u)\n", le16_to_cpu(la->la_size)); status = -EINVAL; goto bail; } /* do a little verification. */ num_used = ocfs2_local_alloc_count_bits(alloc); /* hopefully the local alloc has always been recovered before * we load it. */ if (num_used || alloc->id1.bitmap1.i_used || alloc->id1.bitmap1.i_total || la->la_bm_off) mlog(ML_ERROR, "Local alloc hasn't been recovered!\n" "found = %u, set = %u, taken = %u, off = %u\n", num_used, le32_to_cpu(alloc->id1.bitmap1.i_used), le32_to_cpu(alloc->id1.bitmap1.i_total), OCFS2_LOCAL_ALLOC(alloc)->la_bm_off); osb->local_alloc_bh = alloc_bh; osb->local_alloc_state = OCFS2_LA_ENABLED; bail: if (status < 0) brelse(alloc_bh); if (inode) iput(inode); trace_ocfs2_load_local_alloc(osb->local_alloc_bits); if (status) mlog_errno(status); return status; } /* * return any unused bits to the bitmap and write out a clean * local_alloc. * * local_alloc_bh is optional. If not passed, we will simply use the * one off osb. If you do pass it however, be warned that it *will* be * returned brelse'd and NULL'd out.*/ void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb) { int status; handle_t *handle; struct inode *local_alloc_inode = NULL; struct buffer_head *bh = NULL; struct buffer_head *main_bm_bh = NULL; struct inode *main_bm_inode = NULL; struct ocfs2_dinode *alloc_copy = NULL; struct ocfs2_dinode *alloc = NULL; cancel_delayed_work(&osb->la_enable_wq); flush_workqueue(ocfs2_wq); if (osb->local_alloc_state == OCFS2_LA_UNUSED) goto out; local_alloc_inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE, osb->slot_num); if (!local_alloc_inode) { status = -ENOENT; mlog_errno(status); goto out; } osb->local_alloc_state = OCFS2_LA_DISABLED; ocfs2_resmap_uninit(&osb->osb_la_resmap); main_bm_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE, OCFS2_INVALID_SLOT); if (!main_bm_inode) { status = -EINVAL; mlog_errno(status); goto out; } mutex_lock(&main_bm_inode->i_mutex); status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1); if (status < 0) { mlog_errno(status); goto out_mutex; } /* WINDOW_MOVE_CREDITS is a bit heavy... */ handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); if (IS_ERR(handle)) { mlog_errno(PTR_ERR(handle)); handle = NULL; goto out_unlock; } bh = osb->local_alloc_bh; alloc = (struct ocfs2_dinode *) bh->b_data; alloc_copy = kmalloc(bh->b_size, GFP_NOFS); if (!alloc_copy) { status = -ENOMEM; goto out_commit; } memcpy(alloc_copy, alloc, bh->b_size); status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode), bh, OCFS2_JOURNAL_ACCESS_WRITE); if (status < 0) { mlog_errno(status); goto out_commit; } ocfs2_clear_local_alloc(alloc); ocfs2_journal_dirty(handle, bh); brelse(bh); osb->local_alloc_bh = NULL; osb->local_alloc_state = OCFS2_LA_UNUSED; status = ocfs2_sync_local_to_main(osb, handle, alloc_copy, main_bm_inode, main_bm_bh); if (status < 0) mlog_errno(status); out_commit: ocfs2_commit_trans(osb, handle); out_unlock: brelse(main_bm_bh); ocfs2_inode_unlock(main_bm_inode, 1); out_mutex: mutex_unlock(&main_bm_inode->i_mutex); iput(main_bm_inode); out: if (local_alloc_inode) iput(local_alloc_inode); kfree(alloc_copy); } /* * We want to free the bitmap bits outside of any recovery context as * we'll need a cluster lock to do so, but we must clear the local * alloc before giving up the recovered nodes journal. To solve this, * we kmalloc a copy of the local alloc before it's change for the * caller to process with ocfs2_complete_local_alloc_recovery */ int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb, int slot_num, struct ocfs2_dinode **alloc_copy) { int status = 0; struct buffer_head *alloc_bh = NULL; struct inode *inode = NULL; struct ocfs2_dinode *alloc; trace_ocfs2_begin_local_alloc_recovery(slot_num); *alloc_copy = NULL; inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE, slot_num); if (!inode) { status = -EINVAL; mlog_errno(status); goto bail; } mutex_lock(&inode->i_mutex); status = ocfs2_read_inode_block_full(inode, &alloc_bh, OCFS2_BH_IGNORE_CACHE); if (status < 0) { mlog_errno(status); goto bail; } *alloc_copy = kmalloc(alloc_bh->b_size, GFP_KERNEL); if (!(*alloc_copy)) { status = -ENOMEM; goto bail; } memcpy((*alloc_copy), alloc_bh->b_data, alloc_bh->b_size); alloc = (struct ocfs2_dinode *) alloc_bh->b_data; ocfs2_clear_local_alloc(alloc); ocfs2_compute_meta_ecc(osb->sb, alloc_bh->b_data, &alloc->i_check); status = ocfs2_write_block(osb, alloc_bh, INODE_CACHE(inode)); if (status < 0) mlog_errno(status); bail: if (status < 0) { kfree(*alloc_copy); *alloc_copy = NULL; } brelse(alloc_bh); if (inode) { mutex_unlock(&inode->i_mutex); iput(inode); } if (status) mlog_errno(status); return status; } /* * Step 2: By now, we've completed the journal recovery, we've stamped * a clean local alloc on disk and dropped the node out of the * recovery map. Dlm locks will no longer stall, so lets clear out the * main bitmap. */ int ocfs2_complete_local_alloc_recovery(struct ocfs2_super *osb, struct ocfs2_dinode *alloc) { int status; handle_t *handle; struct buffer_head *main_bm_bh = NULL; struct inode *main_bm_inode; main_bm_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE, OCFS2_INVALID_SLOT); if (!main_bm_inode) { status = -EINVAL; mlog_errno(status); goto out; } mutex_lock(&main_bm_inode->i_mutex); status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1); if (status < 0) { mlog_errno(status); goto out_mutex; } handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); if (IS_ERR(handle)) { status = PTR_ERR(handle); handle = NULL; mlog_errno(status); goto out_unlock; } /* we want the bitmap change to be recorded on disk asap */ handle->h_sync = 1; status = ocfs2_sync_local_to_main(osb, handle, alloc, main_bm_inode, main_bm_bh); if (status < 0) mlog_errno(status); ocfs2_commit_trans(osb, handle); out_unlock: ocfs2_inode_unlock(main_bm_inode, 1); out_mutex: mutex_unlock(&main_bm_inode->i_mutex); brelse(main_bm_bh); iput(main_bm_inode); out: if (!status) ocfs2_init_steal_slots(osb); if (status) mlog_errno(status); return status; } /* * make sure we've got at least bits_wanted contiguous bits in the * local alloc. You lose them when you drop i_mutex. * * We will add ourselves to the transaction passed in, but may start * our own in order to shift windows. */ int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb, u32 bits_wanted, struct ocfs2_alloc_context *ac) { int status; struct ocfs2_dinode *alloc; struct inode *local_alloc_inode; unsigned int free_bits; BUG_ON(!ac); local_alloc_inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE, osb->slot_num); if (!local_alloc_inode) { status = -ENOENT; mlog_errno(status); goto bail; } mutex_lock(&local_alloc_inode->i_mutex); /* * We must double check state and allocator bits because * another process may have changed them while holding i_mutex. */ spin_lock(&osb->osb_lock); if (!ocfs2_la_state_enabled(osb) || (bits_wanted > osb->local_alloc_bits)) { spin_unlock(&osb->osb_lock); status = -ENOSPC; goto bail; } spin_unlock(&osb->osb_lock); alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; #ifdef CONFIG_OCFS2_DEBUG_FS if (le32_to_cpu(alloc->id1.bitmap1.i_used) != ocfs2_local_alloc_count_bits(alloc)) { ocfs2_error(osb->sb, "local alloc inode %llu says it has " "%u free bits, but a count shows %u", (unsigned long long)le64_to_cpu(alloc->i_blkno), le32_to_cpu(alloc->id1.bitmap1.i_used), ocfs2_local_alloc_count_bits(alloc)); status = -EIO; goto bail; } #endif free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) - le32_to_cpu(alloc->id1.bitmap1.i_used); if (bits_wanted > free_bits) { /* uhoh, window change time. */ status = ocfs2_local_alloc_slide_window(osb, local_alloc_inode); if (status < 0) { if (status != -ENOSPC) mlog_errno(status); goto bail; } /* * Under certain conditions, the window slide code * might have reduced the number of bits available or * disabled the the local alloc entirely. Re-check * here and return -ENOSPC if necessary. */ status = -ENOSPC; if (!ocfs2_la_state_enabled(osb)) goto bail; free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) - le32_to_cpu(alloc->id1.bitmap1.i_used); if (bits_wanted > free_bits) goto bail; } ac->ac_inode = local_alloc_inode; /* We should never use localalloc from another slot */ ac->ac_alloc_slot = osb->slot_num; ac->ac_which = OCFS2_AC_USE_LOCAL; get_bh(osb->local_alloc_bh); ac->ac_bh = osb->local_alloc_bh; status = 0; bail: if (status < 0 && local_alloc_inode) { mutex_unlock(&local_alloc_inode->i_mutex); iput(local_alloc_inode); } trace_ocfs2_reserve_local_alloc_bits( (unsigned long long)ac->ac_max_block, bits_wanted, osb->slot_num, status); if (status) mlog_errno(status); return status; } int ocfs2_claim_local_alloc_bits(struct ocfs2_super *osb, handle_t *handle, struct ocfs2_alloc_context *ac, u32 bits_wanted, u32 *bit_off, u32 *num_bits) { int status, start; struct inode *local_alloc_inode; void *bitmap; struct ocfs2_dinode *alloc; struct ocfs2_local_alloc *la; BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL); local_alloc_inode = ac->ac_inode; alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; la = OCFS2_LOCAL_ALLOC(alloc); start = ocfs2_local_alloc_find_clear_bits(osb, alloc, &bits_wanted, ac->ac_resv); if (start == -1) { /* TODO: Shouldn't we just BUG here? */ status = -ENOSPC; mlog_errno(status); goto bail; } bitmap = la->la_bitmap; *bit_off = le32_to_cpu(la->la_bm_off) + start; *num_bits = bits_wanted; status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode), osb->local_alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE); if (status < 0) { mlog_errno(status); goto bail; } ocfs2_resmap_claimed_bits(&osb->osb_la_resmap, ac->ac_resv, start, bits_wanted); while(bits_wanted--) ocfs2_set_bit(start++, bitmap); le32_add_cpu(&alloc->id1.bitmap1.i_used, *num_bits); ocfs2_journal_dirty(handle, osb->local_alloc_bh); bail: if (status) mlog_errno(status); return status; } static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc) { u32 count; struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); count = memweight(la->la_bitmap, le16_to_cpu(la->la_size)); trace_ocfs2_local_alloc_count_bits(count); return count; } static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb, struct ocfs2_dinode *alloc, u32 *numbits, struct ocfs2_alloc_reservation *resv) { int numfound, bitoff, left, startoff, lastzero; int local_resv = 0; struct ocfs2_alloc_reservation r; void *bitmap = NULL; struct ocfs2_reservation_map *resmap = &osb->osb_la_resmap; if (!alloc->id1.bitmap1.i_total) { bitoff = -1; goto bail; } if (!resv) { local_resv = 1; ocfs2_resv_init_once(&r); ocfs2_resv_set_type(&r, OCFS2_RESV_FLAG_TMP); resv = &r; } numfound = *numbits; if (ocfs2_resmap_resv_bits(resmap, resv, &bitoff, &numfound) == 0) { if (numfound < *numbits) *numbits = numfound; goto bail; } /* * Code error. While reservations are enabled, local * allocation should _always_ go through them. */ BUG_ON(osb->osb_resv_level != 0); /* * Reservations are disabled. Handle this the old way. */ bitmap = OCFS2_LOCAL_ALLOC(alloc)->la_bitmap; numfound = bitoff = startoff = 0; lastzero = -1; left = le32_to_cpu(alloc->id1.bitmap1.i_total); while ((bitoff = ocfs2_find_next_zero_bit(bitmap, left, startoff)) != -1) { if (bitoff == left) { /* mlog(0, "bitoff (%d) == left", bitoff); */ break; } /* mlog(0, "Found a zero: bitoff = %d, startoff = %d, " "numfound = %d\n", bitoff, startoff, numfound);*/ /* Ok, we found a zero bit... is it contig. or do we * start over?*/ if (bitoff == startoff) { /* we found a zero */ numfound++; startoff++; } else { /* got a zero after some ones */ numfound = 1; startoff = bitoff+1; } /* we got everything we needed */ if (numfound == *numbits) { /* mlog(0, "Found it all!\n"); */ break; } } trace_ocfs2_local_alloc_find_clear_bits_search_bitmap(bitoff, numfound); if (numfound == *numbits) bitoff = startoff - numfound; else bitoff = -1; bail: if (local_resv) ocfs2_resv_discard(resmap, resv); trace_ocfs2_local_alloc_find_clear_bits(*numbits, le32_to_cpu(alloc->id1.bitmap1.i_total), bitoff, numfound); return bitoff; } static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc) { struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); int i; alloc->id1.bitmap1.i_total = 0; alloc->id1.bitmap1.i_used = 0; la->la_bm_off = 0; for(i = 0; i < le16_to_cpu(la->la_size); i++) la->la_bitmap[i] = 0; } #if 0 /* turn this on and uncomment below to aid debugging window shifts. */ static void ocfs2_verify_zero_bits(unsigned long *bitmap, unsigned int start, unsigned int count) { unsigned int tmp = count; while(tmp--) { if (ocfs2_test_bit(start + tmp, bitmap)) { printk("ocfs2_verify_zero_bits: start = %u, count = " "%u\n", start, count); printk("ocfs2_verify_zero_bits: bit %u is set!", start + tmp); BUG(); } } } #endif /* * sync the local alloc to main bitmap. * * assumes you've already locked the main bitmap -- the bitmap inode * passed is used for caching. */ static int ocfs2_sync_local_to_main(struct ocfs2_super *osb, handle_t *handle, struct ocfs2_dinode *alloc, struct inode *main_bm_inode, struct buffer_head *main_bm_bh) { int status = 0; int bit_off, left, count, start; u64 la_start_blk; u64 blkno; void *bitmap; struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); trace_ocfs2_sync_local_to_main( le32_to_cpu(alloc->id1.bitmap1.i_total), le32_to_cpu(alloc->id1.bitmap1.i_used)); if (!alloc->id1.bitmap1.i_total) { goto bail; } if (le32_to_cpu(alloc->id1.bitmap1.i_used) == le32_to_cpu(alloc->id1.bitmap1.i_total)) { goto bail; } la_start_blk = ocfs2_clusters_to_blocks(osb->sb, le32_to_cpu(la->la_bm_off)); bitmap = la->la_bitmap; start = count = bit_off = 0; left = le32_to_cpu(alloc->id1.bitmap1.i_total); while ((bit_off = ocfs2_find_next_zero_bit(bitmap, left, start)) != -1) { if ((bit_off < left) && (bit_off == start)) { count++; start++; continue; } if (count) { blkno = la_start_blk + ocfs2_clusters_to_blocks(osb->sb, start - count); trace_ocfs2_sync_local_to_main_free( count, start - count, (unsigned long long)la_start_blk, (unsigned long long)blkno); status = ocfs2_release_clusters(handle, main_bm_inode, main_bm_bh, blkno, count); if (status < 0) { mlog_errno(status); goto bail; } } if (bit_off >= left) break; count = 1; start = bit_off + 1; } bail: if (status) mlog_errno(status); return status; } enum ocfs2_la_event { OCFS2_LA_EVENT_SLIDE, /* Normal window slide. */ OCFS2_LA_EVENT_FRAGMENTED, /* The global bitmap has * enough bits theoretically * free, but a contiguous * allocation could not be * found. */ OCFS2_LA_EVENT_ENOSPC, /* Global bitmap doesn't have * enough bits free to satisfy * our request. */ }; #define OCFS2_LA_ENABLE_INTERVAL (30 * HZ) /* * Given an event, calculate the size of our next local alloc window. * * This should always be called under i_mutex of the local alloc inode * so that local alloc disabling doesn't race with processes trying to * use the allocator. * * Returns the state which the local alloc was left in. This value can * be ignored by some paths. */ static int ocfs2_recalc_la_window(struct ocfs2_super *osb, enum ocfs2_la_event event) { unsigned int bits; int state; spin_lock(&osb->osb_lock); if (osb->local_alloc_state == OCFS2_LA_DISABLED) { WARN_ON_ONCE(osb->local_alloc_state == OCFS2_LA_DISABLED); goto out_unlock; } /* * ENOSPC and fragmentation are treated similarly for now. */ if (event == OCFS2_LA_EVENT_ENOSPC || event == OCFS2_LA_EVENT_FRAGMENTED) { /* * We ran out of contiguous space in the primary * bitmap. Drastically reduce the number of bits used * by local alloc until we have to disable it. */ bits = osb->local_alloc_bits >> 1; if (bits > ocfs2_megabytes_to_clusters(osb->sb, 1)) { /* * By setting state to THROTTLED, we'll keep * the number of local alloc bits used down * until an event occurs which would give us * reason to assume the bitmap situation might * have changed. */ osb->local_alloc_state = OCFS2_LA_THROTTLED; osb->local_alloc_bits = bits; } else { osb->local_alloc_state = OCFS2_LA_DISABLED; } queue_delayed_work(ocfs2_wq, &osb->la_enable_wq, OCFS2_LA_ENABLE_INTERVAL); goto out_unlock; } /* * Don't increase the size of the local alloc window until we * know we might be able to fulfill the request. Otherwise, we * risk bouncing around the global bitmap during periods of * low space. */ if (osb->local_alloc_state != OCFS2_LA_THROTTLED) osb->local_alloc_bits = osb->local_alloc_default_bits; out_unlock: state = osb->local_alloc_state; spin_unlock(&osb->osb_lock); return state; } static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb, struct ocfs2_alloc_context **ac, struct inode **bitmap_inode, struct buffer_head **bitmap_bh) { int status; *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL); if (!(*ac)) { status = -ENOMEM; mlog_errno(status); goto bail; } retry_enospc: (*ac)->ac_bits_wanted = osb->local_alloc_default_bits; status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac); if (status == -ENOSPC) { if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_ENOSPC) == OCFS2_LA_DISABLED) goto bail; ocfs2_free_ac_resource(*ac); memset(*ac, 0, sizeof(struct ocfs2_alloc_context)); goto retry_enospc; } if (status < 0) { mlog_errno(status); goto bail; } *bitmap_inode = (*ac)->ac_inode; igrab(*bitmap_inode); *bitmap_bh = (*ac)->ac_bh; get_bh(*bitmap_bh); status = 0; bail: if ((status < 0) && *ac) { ocfs2_free_alloc_context(*ac); *ac = NULL; } if (status) mlog_errno(status); return status; } /* * pass it the bitmap lock in lock_bh if you have it. */ static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb, handle_t *handle, struct ocfs2_alloc_context *ac) { int status = 0; u32 cluster_off, cluster_count; struct ocfs2_dinode *alloc = NULL; struct ocfs2_local_alloc *la; alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; la = OCFS2_LOCAL_ALLOC(alloc); trace_ocfs2_local_alloc_new_window( le32_to_cpu(alloc->id1.bitmap1.i_total), osb->local_alloc_bits); /* Instruct the allocation code to try the most recently used * cluster group. We'll re-record the group used this pass * below. */ ac->ac_last_group = osb->la_last_gd; /* we used the generic suballoc reserve function, but we set * everything up nicely, so there's no reason why we can't use * the more specific cluster api to claim bits. */ status = ocfs2_claim_clusters(handle, ac, osb->local_alloc_bits, &cluster_off, &cluster_count); if (status == -ENOSPC) { retry_enospc: /* * Note: We could also try syncing the journal here to * allow use of any free bits which the current * transaction can't give us access to. --Mark */ if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_FRAGMENTED) == OCFS2_LA_DISABLED) goto bail; ac->ac_bits_wanted = osb->local_alloc_default_bits; status = ocfs2_claim_clusters(handle, ac, osb->local_alloc_bits, &cluster_off, &cluster_count); if (status == -ENOSPC) goto retry_enospc; /* * We only shrunk the *minimum* number of in our * request - it's entirely possible that the allocator * might give us more than we asked for. */ if (status == 0) { spin_lock(&osb->osb_lock); osb->local_alloc_bits = cluster_count; spin_unlock(&osb->osb_lock); } } if (status < 0) { if (status != -ENOSPC) mlog_errno(status); goto bail; } osb->la_last_gd = ac->ac_last_group; la->la_bm_off = cpu_to_le32(cluster_off); alloc->id1.bitmap1.i_total = cpu_to_le32(cluster_count); /* just in case... In the future when we find space ourselves, * we don't have to get all contiguous -- but we'll have to * set all previously used bits in bitmap and update * la_bits_set before setting the bits in the main bitmap. */ alloc->id1.bitmap1.i_used = 0; memset(OCFS2_LOCAL_ALLOC(alloc)->la_bitmap, 0, le16_to_cpu(la->la_size)); ocfs2_resmap_restart(&osb->osb_la_resmap, cluster_count, OCFS2_LOCAL_ALLOC(alloc)->la_bitmap); trace_ocfs2_local_alloc_new_window_result( OCFS2_LOCAL_ALLOC(alloc)->la_bm_off, le32_to_cpu(alloc->id1.bitmap1.i_total)); bail: if (status) mlog_errno(status); return status; } /* Note that we do *NOT* lock the local alloc inode here as * it's been locked already for us. */ static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb, struct inode *local_alloc_inode) { int status = 0; struct buffer_head *main_bm_bh = NULL; struct inode *main_bm_inode = NULL; handle_t *handle = NULL; struct ocfs2_dinode *alloc; struct ocfs2_dinode *alloc_copy = NULL; struct ocfs2_alloc_context *ac = NULL; ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_SLIDE); /* This will lock the main bitmap for us. */ status = ocfs2_local_alloc_reserve_for_window(osb, &ac, &main_bm_inode, &main_bm_bh); if (status < 0) { if (status != -ENOSPC) mlog_errno(status); goto bail; } handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); if (IS_ERR(handle)) { status = PTR_ERR(handle); handle = NULL; mlog_errno(status); goto bail; } alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; /* We want to clear the local alloc before doing anything * else, so that if we error later during this operation, * local alloc shutdown won't try to double free main bitmap * bits. Make a copy so the sync function knows which bits to * free. */ alloc_copy = kmalloc(osb->local_alloc_bh->b_size, GFP_NOFS); if (!alloc_copy) { status = -ENOMEM; mlog_errno(status); goto bail; } memcpy(alloc_copy, alloc, osb->local_alloc_bh->b_size); status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode), osb->local_alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE); if (status < 0) { mlog_errno(status); goto bail; } ocfs2_clear_local_alloc(alloc); ocfs2_journal_dirty(handle, osb->local_alloc_bh); status = ocfs2_sync_local_to_main(osb, handle, alloc_copy, main_bm_inode, main_bm_bh); if (status < 0) { mlog_errno(status); goto bail; } status = ocfs2_local_alloc_new_window(osb, handle, ac); if (status < 0) { if (status != -ENOSPC) mlog_errno(status); goto bail; } atomic_inc(&osb->alloc_stats.moves); bail: if (handle) ocfs2_commit_trans(osb, handle); brelse(main_bm_bh); if (main_bm_inode) iput(main_bm_inode); kfree(alloc_copy); if (ac) ocfs2_free_alloc_context(ac); if (status) mlog_errno(status); return status; }