From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:20:52 +0000
Subject: [PATCH] add new system file
---
kernel/fs/ext2/balloc.c | 94 +++++++++++++++++++----------------------------
1 files changed, 38 insertions(+), 56 deletions(-)
diff --git a/kernel/fs/ext2/balloc.c b/kernel/fs/ext2/balloc.c
index fc59e05..c17ccc1 100644
--- a/kernel/fs/ext2/balloc.c
+++ b/kernel/fs/ext2/balloc.c
@@ -187,7 +187,7 @@
/**
* __rsv_window_dump() -- Dump the filesystem block allocation reservation map
- * @rb_root: root of per-filesystem reservation rb tree
+ * @root: root of per-filesystem reservation rb tree
* @verbose: verbose mode
* @fn: function which wishes to dump the reservation map
*
@@ -267,7 +267,7 @@
ext2_fsblk_t group_first_block, group_last_block;
group_first_block = ext2_group_first_block_no(sb, group);
- group_last_block = group_first_block + EXT2_BLOCKS_PER_GROUP(sb) - 1;
+ group_last_block = ext2_group_last_block_no(sb, group);
if ((rsv->_rsv_start > group_last_block) ||
(rsv->_rsv_end < group_first_block))
@@ -280,7 +280,7 @@
/**
* search_reserve_window()
- * @rb_root: root of reservation tree
+ * @root: root of reservation tree
* @goal: target allocation block
*
* Find the reserved window which includes the goal, or the previous one
@@ -488,9 +488,7 @@
struct ext2_super_block * es = sbi->s_es;
unsigned freed = 0, group_freed;
- if (block < le32_to_cpu(es->s_first_data_block) ||
- block + count < block ||
- block + count > le32_to_cpu(es->s_blocks_count)) {
+ if (!ext2_data_block_valid(sbi, block, count)) {
ext2_error (sb, "ext2_free_blocks",
"Freeing blocks not in datazone - "
"block = %lu, count = %lu", block, count);
@@ -666,37 +664,24 @@
unsigned long *count,
struct ext2_reserve_window *my_rsv)
{
- ext2_fsblk_t group_first_block;
+ ext2_fsblk_t group_first_block = ext2_group_first_block_no(sb, group);
+ ext2_fsblk_t group_last_block = ext2_group_last_block_no(sb, group);
ext2_grpblk_t start, end;
unsigned long num = 0;
+ start = 0;
+ end = group_last_block - group_first_block + 1;
/* we do allocation within the reservation window if we have a window */
if (my_rsv) {
- group_first_block = ext2_group_first_block_no(sb, group);
if (my_rsv->_rsv_start >= group_first_block)
start = my_rsv->_rsv_start - group_first_block;
- else
- /* reservation window cross group boundary */
- start = 0;
- end = my_rsv->_rsv_end - group_first_block + 1;
- if (end > EXT2_BLOCKS_PER_GROUP(sb))
- /* reservation window crosses group boundary */
- end = EXT2_BLOCKS_PER_GROUP(sb);
- if ((start <= grp_goal) && (grp_goal < end))
- start = grp_goal;
- else
+ if (my_rsv->_rsv_end < group_last_block)
+ end = my_rsv->_rsv_end - group_first_block + 1;
+ if (grp_goal < start || grp_goal >= end)
grp_goal = -1;
- } else {
- if (grp_goal > 0)
- start = grp_goal;
- else
- start = 0;
- end = EXT2_BLOCKS_PER_GROUP(sb);
}
-
BUG_ON(start > EXT2_BLOCKS_PER_GROUP(sb));
-repeat:
if (grp_goal < 0) {
grp_goal = find_next_usable_block(start, bitmap_bh, end);
if (grp_goal < 0)
@@ -711,32 +696,23 @@
;
}
}
- start = grp_goal;
- if (ext2_set_bit_atomic(sb_bgl_lock(EXT2_SB(sb), group), grp_goal,
- bitmap_bh->b_data)) {
- /*
- * The block was allocated by another thread, or it was
- * allocated and then freed by another thread
- */
- start++;
- grp_goal++;
- if (start >= end)
- goto fail_access;
- goto repeat;
- }
- num++;
- grp_goal++;
- while (num < *count && grp_goal < end
- && !ext2_set_bit_atomic(sb_bgl_lock(EXT2_SB(sb), group),
+ for (; num < *count && grp_goal < end; grp_goal++) {
+ if (ext2_set_bit_atomic(sb_bgl_lock(EXT2_SB(sb), group),
grp_goal, bitmap_bh->b_data)) {
+ if (num == 0)
+ continue;
+ break;
+ }
num++;
- grp_goal++;
}
+
+ if (num == 0)
+ goto fail_access;
+
*count = num;
return grp_goal - num;
fail_access:
- *count = num;
return -1;
}
@@ -754,10 +730,9 @@
* but we will shift to the place where start_block is,
* then start from there, when looking for a reservable space.
*
- * @size: the target new reservation window size
+ * @sb: the super block.
*
- * @group_first_block: the first block we consider to start
- * the real search from
+ * @start_block: the first block we consider to start the real search from
*
* @last_block:
* the maximum block number that our goal reservable space
@@ -882,7 +857,7 @@
*
* failed: we failed to find a reservation window in this group
*
- * @rsv: the reservation
+ * @my_rsv: the reservation
*
* @grp_goal: The goal (group-relative). It is where the search for a
* free reservable space should start from.
@@ -908,7 +883,7 @@
spinlock_t *rsv_lock = &EXT2_SB(sb)->s_rsv_window_lock;
group_first_block = ext2_group_first_block_no(sb, group);
- group_end_block = group_first_block + (EXT2_BLOCKS_PER_GROUP(sb) - 1);
+ group_end_block = ext2_group_last_block_no(sb, group);
if (grp_goal < 0)
start_block = group_first_block;
@@ -1115,7 +1090,7 @@
* first block is the block number of the first block in this group
*/
group_first_block = ext2_group_first_block_no(sb, group);
- group_last_block = group_first_block + (EXT2_BLOCKS_PER_GROUP(sb) - 1);
+ group_last_block = ext2_group_last_block_no(sb, group);
/*
* Basically we will allocate a new block from inode's reservation
@@ -1195,21 +1170,20 @@
/*
* Returns 1 if the passed-in block region is valid; 0 if some part overlaps
- * with filesystem metadata blocksi.
+ * with filesystem metadata blocks.
*/
int ext2_data_block_valid(struct ext2_sb_info *sbi, ext2_fsblk_t start_blk,
unsigned int count)
{
if ((start_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
- (start_blk + count < start_blk) ||
- (start_blk > le32_to_cpu(sbi->s_es->s_blocks_count)))
+ (start_blk + count - 1 < start_blk) ||
+ (start_blk + count - 1 >= le32_to_cpu(sbi->s_es->s_blocks_count)))
return 0;
/* Ensure we do not step over superblock */
if ((start_blk <= sbi->s_sb_block) &&
- (start_blk + count >= sbi->s_sb_block))
+ (start_blk + count - 1 >= sbi->s_sb_block))
return 0;
-
return 1;
}
@@ -1314,6 +1288,13 @@
if (free_blocks > 0) {
grp_target_blk = ((goal - le32_to_cpu(es->s_first_data_block)) %
EXT2_BLOCKS_PER_GROUP(sb));
+ /*
+ * In case we retry allocation (due to fs reservation not
+ * working out or fs corruption), the bitmap_bh is non-null
+ * pointer and we have to release it before calling
+ * read_block_bitmap().
+ */
+ brelse(bitmap_bh);
bitmap_bh = read_block_bitmap(sb, group_no);
if (!bitmap_bh)
goto io_error;
@@ -1405,6 +1386,7 @@
* use. So we may want to selectively mark some of the blocks
* as free
*/
+ num = *count;
goto retry_alloc;
}
--
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