summaryrefslogtreecommitdiffstats
path: root/fs/ocfs2/localalloc.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ocfs2/localalloc.c')
-rw-r--r--fs/ocfs2/localalloc.c1324
1 files changed, 1324 insertions, 0 deletions
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
new file mode 100644
index 000000000..c4426d12a
--- /dev/null
+++ b/fs/ocfs2/localalloc.c
@@ -0,0 +1,1324 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * localalloc.c
+ *
+ * Node local data allocation
+ *
+ * Copyright (C) 2002, 2004 Oracle. All rights reserved.
+ */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/bitops.h>
+
+#include <cluster/masklog.h>
+
+#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, "inconsistent detected, clean journal with"
+ " unrecovered local alloc, please run fsck.ocfs2!\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);
+
+ status = -EINVAL;
+ goto bail;
+ }
+
+ osb->local_alloc_bh = alloc_bh;
+ osb->local_alloc_state = OCFS2_LA_ENABLED;
+
+bail:
+ if (status < 0)
+ brelse(alloc_bh);
+ 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);
+ if (osb->ocfs2_wq)
+ flush_workqueue(osb->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;
+ }
+
+ inode_lock(main_bm_inode);
+
+ 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 = kmemdup(alloc, bh->b_size, GFP_NOFS);
+ if (!alloc_copy) {
+ status = -ENOMEM;
+ goto out_commit;
+ }
+
+ 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:
+ inode_unlock(main_bm_inode);
+ iput(main_bm_inode);
+
+out:
+ 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;
+ }
+
+ inode_lock(inode);
+
+ 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) {
+ inode_unlock(inode);
+ 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;
+ }
+
+ inode_lock(main_bm_inode);
+
+ 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:
+ inode_unlock(main_bm_inode);
+
+ 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_rwsem.
+ *
+ * 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;
+ }
+
+ inode_lock(local_alloc_inode);
+
+ /*
+ * We must double check state and allocator bits because
+ * another process may have changed them while holding i_rwsem.
+ */
+ 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)) {
+ status = ocfs2_error(osb->sb, "local alloc inode %llu says it has %u used bits, but a count shows %u\n",
+ (unsigned long long)le64_to_cpu(alloc->i_blkno),
+ le32_to_cpu(alloc->id1.bitmap1.i_used),
+ ocfs2_local_alloc_count_bits(alloc));
+ 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 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) {
+ inode_unlock(local_alloc_inode);
+ 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;
+}
+
+int ocfs2_free_local_alloc_bits(struct ocfs2_super *osb,
+ handle_t *handle,
+ struct ocfs2_alloc_context *ac,
+ u32 bit_off,
+ u32 num_bits)
+{
+ int status, start;
+ u32 clear_bits;
+ 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);
+
+ bitmap = la->la_bitmap;
+ start = bit_off - le32_to_cpu(la->la_bm_off);
+ clear_bits = num_bits;
+
+ 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;
+ }
+
+ while (clear_bits--)
+ ocfs2_clear_bit(start++, bitmap);
+
+ le32_add_cpu(&alloc->id1.bitmap1.i_used, -num_bits);
+ ocfs2_journal_dirty(handle, osb->local_alloc_bh);
+
+bail:
+ 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 = 0, bitoff, left, startoff;
+ 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;
+ 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_rwsem 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(osb->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_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_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 = kmemdup(alloc, osb->local_alloc_bh->b_size, GFP_NOFS);
+ if (!alloc_copy) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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);
+
+ iput(main_bm_inode);
+ kfree(alloc_copy);
+
+ if (ac)
+ ocfs2_free_alloc_context(ac);
+
+ if (status)
+ mlog_errno(status);
+ return status;
+}
+