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Message-Id: <1325653654-10478-13-git-send-email-tytso@mit.edu>
Date: Wed, 4 Jan 2012 00:07:34 -0500
From: Theodore Ts'o <tytso@....edu>
To: Ext4 Developers List <linux-ext4@...r.kernel.org>
Cc: Yongqiang Yang <xiaoqiangnk@...il.com>,
"Theodore Ts'o" <tytso@....edu>
Subject: [PATCH V7 12/12] ext4: let ext4_group_add() use common code
From: Yongqiang Yang <xiaoqiangnk@...il.com>
This patch lets ext4_group_add() call ext4_flex_group_add().
Signed-off-by: Yongqiang Yang <xiaoqiangnk@...il.com>
Signed-off-by: "Theodore Ts'o" <tytso@....edu>
---
fs/ext4/resize.c | 309 ++----------------------------------------------------
1 files changed, 10 insertions(+), 299 deletions(-)
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index eba706d..f9d948f 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -595,137 +595,6 @@ out:
}
/*
- * Set up the block and inode bitmaps, and the inode table for the new group.
- * This doesn't need to be part of the main transaction, since we are only
- * changing blocks outside the actual filesystem. We still do journaling to
- * ensure the recovery is correct in case of a failure just after resize.
- * If any part of this fails, we simply abort the resize.
- */
-static int setup_new_group_blocks(struct super_block *sb,
- struct ext4_new_group_data *input)
-{
- struct ext4_sb_info *sbi = EXT4_SB(sb);
- ext4_fsblk_t start = ext4_group_first_block_no(sb, input->group);
- int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
- le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0;
- unsigned long gdblocks = ext4_bg_num_gdb(sb, input->group);
- struct buffer_head *bh;
- handle_t *handle;
- ext4_fsblk_t block;
- ext4_grpblk_t bit;
- int i;
- int err = 0, err2;
-
- /* This transaction may be extended/restarted along the way */
- handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
-
- if (IS_ERR(handle))
- return PTR_ERR(handle);
-
- BUG_ON(input->group != sbi->s_groups_count);
-
- /* Copy all of the GDT blocks into the backup in this group */
- for (i = 0, bit = 1, block = start + 1;
- i < gdblocks; i++, block++, bit++) {
- struct buffer_head *gdb;
-
- ext4_debug("update backup group %#04llx (+%d)\n", block, bit);
- err = extend_or_restart_transaction(handle, 1);
- if (err)
- goto exit_journal;
-
- gdb = sb_getblk(sb, block);
- if (!gdb) {
- err = -EIO;
- goto exit_journal;
- }
- if ((err = ext4_journal_get_write_access(handle, gdb))) {
- brelse(gdb);
- goto exit_journal;
- }
- memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, gdb->b_size);
- set_buffer_uptodate(gdb);
- err = ext4_handle_dirty_metadata(handle, NULL, gdb);
- if (unlikely(err)) {
- brelse(gdb);
- goto exit_journal;
- }
- brelse(gdb);
- }
-
- /* Zero out all of the reserved backup group descriptor table blocks */
- ext4_debug("clear inode table blocks %#04llx -> %#04lx\n",
- block, sbi->s_itb_per_group);
- err = sb_issue_zeroout(sb, gdblocks + start + 1, reserved_gdb,
- GFP_NOFS);
- if (err)
- goto exit_journal;
-
- err = extend_or_restart_transaction(handle, 2);
- if (err)
- goto exit_journal;
-
- bh = bclean(handle, sb, input->block_bitmap);
- if (IS_ERR(bh)) {
- err = PTR_ERR(bh);
- goto exit_journal;
- }
-
- if (ext4_bg_has_super(sb, input->group)) {
- ext4_debug("mark backup group tables %#04llx (+0)\n", start);
- ext4_set_bits(bh->b_data, 0, gdblocks + reserved_gdb + 1);
- }
-
- ext4_debug("mark block bitmap %#04llx (+%llu)\n", input->block_bitmap,
- input->block_bitmap - start);
- ext4_set_bit(input->block_bitmap - start, bh->b_data);
- ext4_debug("mark inode bitmap %#04llx (+%llu)\n", input->inode_bitmap,
- input->inode_bitmap - start);
- ext4_set_bit(input->inode_bitmap - start, bh->b_data);
-
- /* Zero out all of the inode table blocks */
- block = input->inode_table;
- ext4_debug("clear inode table blocks %#04llx -> %#04lx\n",
- block, sbi->s_itb_per_group);
- err = sb_issue_zeroout(sb, block, sbi->s_itb_per_group, GFP_NOFS);
- if (err)
- goto exit_bh;
- ext4_set_bits(bh->b_data, input->inode_table - start,
- sbi->s_itb_per_group);
-
-
- ext4_mark_bitmap_end(input->blocks_count, sb->s_blocksize * 8,
- bh->b_data);
- err = ext4_handle_dirty_metadata(handle, NULL, bh);
- if (unlikely(err)) {
- ext4_std_error(sb, err);
- goto exit_bh;
- }
- brelse(bh);
- /* Mark unused entries in inode bitmap used */
- ext4_debug("clear inode bitmap %#04llx (+%llu)\n",
- input->inode_bitmap, input->inode_bitmap - start);
- if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) {
- err = PTR_ERR(bh);
- goto exit_journal;
- }
-
- ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
- bh->b_data);
- err = ext4_handle_dirty_metadata(handle, NULL, bh);
- if (unlikely(err))
- ext4_std_error(sb, err);
-exit_bh:
- brelse(bh);
-
-exit_journal:
- if ((err2 = ext4_journal_stop(handle)) && !err)
- err = err2;
-
- return err;
-}
-
-/*
* Iterate through the groups which hold BACKUP superblock/GDT copies in an
* ext4 filesystem. The counters should be initialized to 1, 5, and 7 before
* calling this for the first time. In a sparse filesystem it will be the
@@ -1509,16 +1378,15 @@ static int ext4_setup_next_flex_gd(struct super_block *sb,
*/
int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
{
+ struct ext4_new_flex_group_data flex_gd;
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct ext4_super_block *es = sbi->s_es;
int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
- struct buffer_head *primary = NULL;
- struct ext4_group_desc *gdp;
struct inode *inode = NULL;
- handle_t *handle;
int gdb_off, gdb_num;
- int err, err2;
+ int err;
+ __u16 bg_flags = 0;
gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb);
@@ -1557,172 +1425,15 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
}
- if ((err = verify_group_input(sb, input)))
- goto exit_put;
-
- if ((err = setup_new_group_blocks(sb, input)))
- goto exit_put;
-
- /*
- * We will always be modifying at least the superblock and a GDT
- * block. If we are adding a group past the last current GDT block,
- * we will also modify the inode and the dindirect block. If we
- * are adding a group with superblock/GDT backups we will also
- * modify each of the reserved GDT dindirect blocks.
- */
- handle = ext4_journal_start_sb(sb,
- ext4_bg_has_super(sb, input->group) ?
- 3 + reserved_gdb : 4);
- if (IS_ERR(handle)) {
- err = PTR_ERR(handle);
- goto exit_put;
- }
-
- if ((err = ext4_journal_get_write_access(handle, sbi->s_sbh)))
- goto exit_journal;
-
- /*
- * We will only either add reserved group blocks to a backup group
- * or remove reserved blocks for the first group in a new group block.
- * Doing both would be mean more complex code, and sane people don't
- * use non-sparse filesystems anymore. This is already checked above.
- */
- if (gdb_off) {
- primary = sbi->s_group_desc[gdb_num];
- if ((err = ext4_journal_get_write_access(handle, primary)))
- goto exit_journal;
-
- if (reserved_gdb && ext4_bg_num_gdb(sb, input->group)) {
- err = reserve_backup_gdb(handle, inode, input->group);
- if (err)
- goto exit_journal;
- }
- } else {
- /*
- * Note that we can access new group descriptor block safely
- * only if add_new_gdb() succeeds.
- */
- err = add_new_gdb(handle, inode, input->group);
- if (err)
- goto exit_journal;
- primary = sbi->s_group_desc[gdb_num];
- }
-
- /*
- * OK, now we've set up the new group. Time to make it active.
- *
- * so we have to be safe wrt. concurrent accesses the group
- * data. So we need to be careful to set all of the relevant
- * group descriptor data etc. *before* we enable the group.
- *
- * The key field here is sbi->s_groups_count: as long as
- * that retains its old value, nobody is going to access the new
- * group.
- *
- * So first we update all the descriptor metadata for the new
- * group; then we update the total disk blocks count; then we
- * update the groups count to enable the group; then finally we
- * update the free space counts so that the system can start
- * using the new disk blocks.
- */
-
- /* Update group descriptor block for new group */
- gdp = (struct ext4_group_desc *)((char *)primary->b_data +
- gdb_off * EXT4_DESC_SIZE(sb));
-
- memset(gdp, 0, EXT4_DESC_SIZE(sb));
- ext4_block_bitmap_set(sb, gdp, input->block_bitmap); /* LV FIXME */
- ext4_inode_bitmap_set(sb, gdp, input->inode_bitmap); /* LV FIXME */
- ext4_inode_table_set(sb, gdp, input->inode_table); /* LV FIXME */
- ext4_free_group_clusters_set(sb, gdp, input->free_blocks_count);
- ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb));
- gdp->bg_flags = cpu_to_le16(EXT4_BG_INODE_ZEROED);
- gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp);
-
- /*
- * We can allocate memory for mb_alloc based on the new group
- * descriptor
- */
- err = ext4_mb_add_groupinfo(sb, input->group, gdp);
+ err = verify_group_input(sb, input);
if (err)
- goto exit_journal;
-
- /*
- * Make the new blocks and inodes valid next. We do this before
- * increasing the group count so that once the group is enabled,
- * all of its blocks and inodes are already valid.
- *
- * We always allocate group-by-group, then block-by-block or
- * inode-by-inode within a group, so enabling these
- * blocks/inodes before the group is live won't actually let us
- * allocate the new space yet.
- */
- ext4_blocks_count_set(es, ext4_blocks_count(es) +
- input->blocks_count);
- le32_add_cpu(&es->s_inodes_count, EXT4_INODES_PER_GROUP(sb));
-
- /*
- * We need to protect s_groups_count against other CPUs seeing
- * inconsistent state in the superblock.
- *
- * The precise rules we use are:
- *
- * * Writers must perform a smp_wmb() after updating all dependent
- * data and before modifying the groups count
- *
- * * Readers must perform an smp_rmb() after reading the groups count
- * and before reading any dependent data.
- *
- * NB. These rules can be relaxed when checking the group count
- * while freeing data, as we can only allocate from a block
- * group after serialising against the group count, and we can
- * only then free after serialising in turn against that
- * allocation.
- */
- smp_wmb();
-
- /* Update the global fs size fields */
- sbi->s_groups_count++;
-
- err = ext4_handle_dirty_metadata(handle, NULL, primary);
- if (unlikely(err)) {
- ext4_std_error(sb, err);
- goto exit_journal;
- }
-
- /* Update the reserved block counts only once the new group is
- * active. */
- ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) +
- input->reserved_blocks);
-
- /* Update the free space counts */
- percpu_counter_add(&sbi->s_freeclusters_counter,
- EXT4_B2C(sbi, input->free_blocks_count));
- percpu_counter_add(&sbi->s_freeinodes_counter,
- EXT4_INODES_PER_GROUP(sb));
-
- if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
- sbi->s_log_groups_per_flex) {
- ext4_group_t flex_group;
- flex_group = ext4_flex_group(sbi, input->group);
- atomic_add(EXT4_B2C(sbi, input->free_blocks_count),
- &sbi->s_flex_groups[flex_group].free_clusters);
- atomic_add(EXT4_INODES_PER_GROUP(sb),
- &sbi->s_flex_groups[flex_group].free_inodes);
- }
-
- ext4_handle_dirty_super(handle, sb);
+ goto out;
-exit_journal:
- if ((err2 = ext4_journal_stop(handle)) && !err)
- err = err2;
- if (!err && primary) {
- update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
- sizeof(struct ext4_super_block));
- update_backups(sb, primary->b_blocknr, primary->b_data,
- primary->b_size);
- }
-exit_put:
+ flex_gd.count = 1;
+ flex_gd.groups = input;
+ flex_gd.bg_flags = &bg_flags;
+ err = ext4_flex_group_add(sb, inode, &flex_gd);
+out:
iput(inode);
return err;
} /* ext4_group_add */
--
1.7.8.11.gefc1f.dirty
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