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authorMark Fasheh <mark.fasheh@oracle.com>2005-12-15 14:31:24 -0800
committerJoel Becker <joel.becker@oracle.com>2006-01-03 11:45:47 -0800
commitccd979bdbce9fba8412beb3f1de68a9d0171b12c (patch)
treec50ed941849ce06ccadd4ce27599b3ef9fdbe2ae /fs/ocfs2/localalloc.c
parent8df08c89c668e1bd922a053fdb5ba1fadbecbb38 (diff)
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[PATCH] OCFS2: The Second Oracle Cluster Filesystem
The OCFS2 file system module. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
Diffstat (limited to 'fs/ocfs2/localalloc.c')
-rw-r--r--fs/ocfs2/localalloc.c983
1 files changed, 983 insertions, 0 deletions
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
new file mode 100644
index 00000000000..fe373a2101d
--- /dev/null
+++ b/fs/ocfs2/localalloc.c
@@ -0,0 +1,983 @@
+/* -*- 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 <linux/fs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/bitops.h>
+
+#define MLOG_MASK_PREFIX ML_DISK_ALLOC
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "dlmglue.h"
+#include "inode.h"
+#include "journal.h"
+#include "localalloc.h"
+#include "suballoc.h"
+#include "super.h"
+#include "sysfile.h"
+
+#include "buffer_head_io.h"
+
+#define OCFS2_LOCAL_ALLOC(dinode) (&((dinode)->id2.i_lab))
+
+static inline int ocfs2_local_alloc_window_bits(struct ocfs2_super *osb);
+
+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);
+
+static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc);
+
+static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
+ struct ocfs2_journal_handle *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_journal_handle *handle,
+ 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,
+ struct ocfs2_journal_handle *handle,
+ struct ocfs2_alloc_context *ac);
+
+static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
+ struct inode *local_alloc_inode);
+
+/*
+ * Determine how large our local alloc window should be, in bits.
+ *
+ * These values (and the behavior in ocfs2_alloc_should_use_local) have
+ * been chosen so that most allocations, including new block groups go
+ * through local alloc.
+ */
+static inline int ocfs2_local_alloc_window_bits(struct ocfs2_super *osb)
+{
+ BUG_ON(osb->s_clustersize_bits < 12);
+
+ return 2048 >> (osb->s_clustersize_bits - 12);
+}
+
+/*
+ * Tell us whether a given allocation should use the local alloc
+ * file. Otherwise, it has to go to the main bitmap.
+ */
+int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits)
+{
+ int la_bits = ocfs2_local_alloc_window_bits(osb);
+
+ if (osb->local_alloc_state != OCFS2_LA_ENABLED)
+ return 0;
+
+ /* 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))
+ return 0;
+
+ return 1;
+}
+
+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;
+
+ mlog_entry_void();
+
+ /* 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_block(osb, OCFS2_I(inode)->ip_blkno,
+ &alloc_bh, 0, inode);
+ 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, %"MLFu64"\n",
+ 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)
+ if (alloc_bh)
+ brelse(alloc_bh);
+ if (inode)
+ iput(inode);
+
+ mlog_exit(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;
+ struct ocfs2_journal_handle *handle = NULL;
+ 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;
+
+ mlog_entry_void();
+
+ if (osb->local_alloc_state == OCFS2_LA_UNUSED)
+ goto bail;
+
+ 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;
+ }
+
+ osb->local_alloc_state = OCFS2_LA_DISABLED;
+
+ handle = ocfs2_alloc_handle(osb);
+ if (!handle) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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 bail;
+ }
+
+ ocfs2_handle_add_inode(handle, main_bm_inode);
+ status = ocfs2_meta_lock(main_bm_inode, handle, &main_bm_bh, 1);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ /* WINDOW_MOVE_CREDITS is a bit heavy... */
+ handle = ocfs2_start_trans(osb, handle, OCFS2_WINDOW_MOVE_CREDITS);
+ if (IS_ERR(handle)) {
+ mlog_errno(PTR_ERR(handle));
+ handle = NULL;
+ goto bail;
+ }
+
+ bh = osb->local_alloc_bh;
+ alloc = (struct ocfs2_dinode *) bh->b_data;
+
+ alloc_copy = kmalloc(bh->b_size, GFP_KERNEL);
+ if (!alloc_copy) {
+ status = -ENOMEM;
+ goto bail;
+ }
+ memcpy(alloc_copy, alloc, bh->b_size);
+
+ status = ocfs2_journal_access(handle, local_alloc_inode, bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ ocfs2_clear_local_alloc(alloc);
+
+ status = ocfs2_journal_dirty(handle, bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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);
+
+bail:
+ if (handle)
+ ocfs2_commit_trans(handle);
+
+ if (main_bm_bh)
+ brelse(main_bm_bh);
+
+ if (main_bm_inode)
+ iput(main_bm_inode);
+
+ if (local_alloc_inode)
+ iput(local_alloc_inode);
+
+ if (alloc_copy)
+ kfree(alloc_copy);
+
+ mlog_exit_void();
+}
+
+/*
+ * 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;
+
+ mlog_entry("(slot_num = %d)\n", 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;
+ }
+
+ down(&inode->i_sem);
+
+ status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno,
+ &alloc_bh, 0, inode);
+ 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);
+
+ status = ocfs2_write_block(osb, alloc_bh, inode);
+ if (status < 0)
+ mlog_errno(status);
+
+bail:
+ if ((status < 0) && (*alloc_copy)) {
+ kfree(*alloc_copy);
+ *alloc_copy = NULL;
+ }
+
+ if (alloc_bh)
+ brelse(alloc_bh);
+
+ if (inode) {
+ up(&inode->i_sem);
+ iput(inode);
+ }
+
+ mlog_exit(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;
+ struct ocfs2_journal_handle *handle = NULL;
+ struct buffer_head *main_bm_bh = NULL;
+ struct inode *main_bm_inode = NULL;
+
+ mlog_entry_void();
+
+ handle = ocfs2_alloc_handle(osb);
+ if (!handle) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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 bail;
+ }
+
+ ocfs2_handle_add_inode(handle, main_bm_inode);
+ status = ocfs2_meta_lock(main_bm_inode, handle, &main_bm_bh, 1);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ handle = ocfs2_start_trans(osb, handle, OCFS2_WINDOW_MOVE_CREDITS);
+ if (IS_ERR(handle)) {
+ status = PTR_ERR(handle);
+ handle = NULL;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ /* we want the bitmap change to be recorded on disk asap */
+ ocfs2_handle_set_sync(handle, 1);
+
+ status = ocfs2_sync_local_to_main(osb, handle, alloc,
+ main_bm_inode, main_bm_bh);
+ if (status < 0)
+ mlog_errno(status);
+
+bail:
+ if (handle)
+ ocfs2_commit_trans(handle);
+
+ if (main_bm_bh)
+ brelse(main_bm_bh);
+
+ if (main_bm_inode)
+ iput(main_bm_inode);
+
+ mlog_exit(status);
+ return status;
+}
+
+/*
+ * make sure we've got at least bitswanted contiguous bits in the
+ * local alloc. You lose them when you drop i_sem.
+ *
+ * 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,
+ struct ocfs2_journal_handle *passed_handle,
+ u32 bits_wanted,
+ struct ocfs2_alloc_context *ac)
+{
+ int status;
+ struct ocfs2_dinode *alloc;
+ struct inode *local_alloc_inode;
+ unsigned int free_bits;
+
+ mlog_entry_void();
+
+ BUG_ON(!passed_handle);
+ BUG_ON(!ac);
+ BUG_ON(passed_handle->flags & OCFS2_HANDLE_STARTED);
+
+ 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;
+ }
+ ocfs2_handle_add_inode(passed_handle, local_alloc_inode);
+
+ if (osb->local_alloc_state != OCFS2_LA_ENABLED) {
+ status = -ENOSPC;
+ goto bail;
+ }
+
+ if (bits_wanted > ocfs2_local_alloc_window_bits(osb)) {
+ mlog(0, "Asking for more than my max window size!\n");
+ status = -ENOSPC;
+ goto bail;
+ }
+
+ alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
+
+ if (le32_to_cpu(alloc->id1.bitmap1.i_used) !=
+ ocfs2_local_alloc_count_bits(alloc)) {
+ ocfs2_error(osb->sb, "local alloc inode %"MLFu64" says it has "
+ "%u free bits, but a count shows %u",
+ le64_to_cpu(alloc->i_blkno),
+ le32_to_cpu(alloc->id1.bitmap1.i_used),
+ ocfs2_local_alloc_count_bits(alloc));
+ status = -EIO;
+ 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) {
+ /* 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;
+ }
+ }
+
+ ac->ac_inode = igrab(local_alloc_inode);
+ get_bh(osb->local_alloc_bh);
+ ac->ac_bh = osb->local_alloc_bh;
+ ac->ac_which = OCFS2_AC_USE_LOCAL;
+ status = 0;
+bail:
+ if (local_alloc_inode)
+ iput(local_alloc_inode);
+
+ mlog_exit(status);
+ return status;
+}
+
+int ocfs2_claim_local_alloc_bits(struct ocfs2_super *osb,
+ struct ocfs2_journal_handle *handle,
+ struct ocfs2_alloc_context *ac,
+ u32 min_bits,
+ u32 *bit_off,
+ u32 *num_bits)
+{
+ int status, start;
+ struct inode *local_alloc_inode;
+ u32 bits_wanted;
+ void *bitmap;
+ struct ocfs2_dinode *alloc;
+ struct ocfs2_local_alloc *la;
+
+ mlog_entry_void();
+ BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL);
+
+ bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
+ 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);
+ 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;
+ /* local alloc is always contiguous by nature -- we never
+ * delete bits from it! */
+ *num_bits = bits_wanted;
+
+ status = ocfs2_journal_access(handle, local_alloc_inode,
+ osb->local_alloc_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ while(bits_wanted--)
+ ocfs2_set_bit(start++, bitmap);
+
+ alloc->id1.bitmap1.i_used = cpu_to_le32(*num_bits +
+ le32_to_cpu(alloc->id1.bitmap1.i_used));
+
+ status = ocfs2_journal_dirty(handle, osb->local_alloc_bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ status = 0;
+bail:
+ mlog_exit(status);
+ return status;
+}
+
+static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc)
+{
+ int i;
+ u8 *buffer;
+ u32 count = 0;
+ struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
+
+ mlog_entry_void();
+
+ buffer = la->la_bitmap;
+ for (i = 0; i < le16_to_cpu(la->la_size); i++)
+ count += hweight8(buffer[i]);
+
+ mlog_exit(count);
+ return count;
+}
+
+static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
+ struct ocfs2_dinode *alloc,
+ u32 numbits)
+{
+ int numfound, bitoff, left, startoff, lastzero;
+ void *bitmap = NULL;
+
+ mlog_entry("(numbits wanted = %u)\n", numbits);
+
+ if (!alloc->id1.bitmap1.i_total) {
+ mlog(0, "No bits in my window!\n");
+ bitoff = -1;
+ goto bail;
+ }
+
+ 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;
+ }
+ }
+
+ mlog(0, "Exiting loop, bitoff = %d, numfound = %d\n", bitoff,
+ numfound);
+
+ if (numfound == numbits)
+ bitoff = startoff - numfound;
+ else
+ bitoff = -1;
+
+bail:
+ mlog_exit(bitoff);
+ return bitoff;
+}
+
+static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc)
+{
+ struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
+ int i;
+ mlog_entry_void();
+
+ 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;
+
+ mlog_exit_void();
+}
+
+#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,
+ struct ocfs2_journal_handle *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);
+
+ mlog_entry("total = %u, COUNT = %u, used = %u\n",
+ le32_to_cpu(alloc->id1.bitmap1.i_total),
+ ocfs2_local_alloc_count_bits(alloc),
+ le32_to_cpu(alloc->id1.bitmap1.i_used));
+
+ if (!alloc->id1.bitmap1.i_total) {
+ mlog(0, "nothing to sync!\n");
+ goto bail;
+ }
+
+ if (le32_to_cpu(alloc->id1.bitmap1.i_used) ==
+ le32_to_cpu(alloc->id1.bitmap1.i_total)) {
+ mlog(0, "all bits were taken!\n");
+ 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);
+
+ mlog(0, "freeing %u bits starting at local "
+ "alloc bit %u (la_start_blk = %"MLFu64", "
+ "blkno = %"MLFu64")\n", count, start - count,
+ la_start_blk, blkno);
+
+ status = ocfs2_free_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:
+ mlog_exit(status);
+ return status;
+}
+
+static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
+ struct ocfs2_journal_handle *handle,
+ struct ocfs2_alloc_context **ac,
+ struct inode **bitmap_inode,
+ struct buffer_head **bitmap_bh)
+{
+ int status;
+
+ *ac = kcalloc(1, sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
+ if (!(*ac)) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ (*ac)->ac_handle = handle;
+ (*ac)->ac_bits_wanted = ocfs2_local_alloc_window_bits(osb);
+
+ status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
+ if (status < 0) {
+ if (status != -ENOSPC)
+ 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;
+ }
+
+ mlog_exit(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,
+ struct ocfs2_journal_handle *handle,
+ struct ocfs2_alloc_context *ac)
+{
+ int status = 0;
+ u32 cluster_off, cluster_count;
+ struct ocfs2_dinode *alloc = NULL;
+ struct ocfs2_local_alloc *la;
+
+ mlog_entry_void();
+
+ alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
+ la = OCFS2_LOCAL_ALLOC(alloc);
+
+ if (alloc->id1.bitmap1.i_total)
+ mlog(0, "asking me to alloc a new window over a non-empty "
+ "one\n");
+
+ mlog(0, "Allocating %u clusters for a new window.\n",
+ ocfs2_local_alloc_window_bits(osb));
+ /* 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(osb, handle, ac,
+ ocfs2_local_alloc_window_bits(osb),
+ &cluster_off, &cluster_count);
+ if (status < 0) {
+ if (status != -ENOSPC)
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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));
+
+ mlog(0, "New window allocated:\n");
+ mlog(0, "window la_bm_off = %u\n",
+ OCFS2_LOCAL_ALLOC(alloc)->la_bm_off);
+ mlog(0, "window bits = %u\n", le32_to_cpu(alloc->id1.bitmap1.i_total));
+
+bail:
+ mlog_exit(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;
+ struct ocfs2_journal_handle *handle = NULL;
+ struct ocfs2_dinode *alloc;
+ struct ocfs2_dinode *alloc_copy = NULL;
+ struct ocfs2_alloc_context *ac = NULL;
+
+ mlog_entry_void();
+
+ handle = ocfs2_alloc_handle(osb);
+ if (!handle) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ /* This will lock the main bitmap for us. */
+ status = ocfs2_local_alloc_reserve_for_window(osb,
+ handle,
+ &ac,
+ &main_bm_inode,
+ &main_bm_bh);
+ if (status < 0) {
+ if (status != -ENOSPC)
+ mlog_errno(status);
+ goto bail;
+ }
+
+ handle = ocfs2_start_trans(osb, handle, 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_KERNEL);
+ if (!alloc_copy) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+ memcpy(alloc_copy, alloc, osb->local_alloc_bh->b_size);
+
+ status = ocfs2_journal_access(handle, local_alloc_inode,
+ osb->local_alloc_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ ocfs2_clear_local_alloc(alloc);
+
+ status = ocfs2_journal_dirty(handle, osb->local_alloc_bh);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+ }
+
+ 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);
+
+ status = 0;
+bail:
+ if (handle)
+ ocfs2_commit_trans(handle);
+
+ if (main_bm_bh)
+ brelse(main_bm_bh);
+
+ if (main_bm_inode)
+ iput(main_bm_inode);
+
+ if (alloc_copy)
+ kfree(alloc_copy);
+
+ if (ac)
+ ocfs2_free_alloc_context(ac);
+
+ mlog_exit(status);
+ return status;
+}
+