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authorYuezhang Mo <Yuezhang.Mo@sony.com>2022-11-09 06:50:22 +0100
committerNamjae Jeon <linkinjeon@kernel.org>2022-12-12 03:02:49 +0100
commita3ff29a95fde16906304455aa8c0bd84eb770258 (patch)
tree57350d5839a840354048b8438215f98debad2008 /fs/exfat
parentexfat: reduce the size of exfat_entry_set_cache (diff)
downloadlinux-a3ff29a95fde16906304455aa8c0bd84eb770258.tar.xz
linux-a3ff29a95fde16906304455aa8c0bd84eb770258.zip
exfat: support dynamic allocate bh for exfat_entry_set_cache
In special cases, a file or a directory may occupied more than 19 directory entries, pre-allocating 3 bh is not enough. Such as - Support vendor secondary directory entry in the future. - Since file directory entry is damaged, the SecondaryCount field is bigger than 18. So this commit supports dynamic allocation of bh. Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com> Reviewed-by: Andy Wu <Andy.Wu@sony.com> Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com> Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Diffstat (limited to 'fs/exfat')
-rw-r--r--fs/exfat/dir.c15
-rw-r--r--fs/exfat/exfat_fs.h5
2 files changed, 19 insertions, 1 deletions
diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c
index 30d0ac43b66c..03e9c9e3966e 100644
--- a/fs/exfat/dir.c
+++ b/fs/exfat/dir.c
@@ -615,6 +615,10 @@ int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync)
bforget(es->bh[i]);
else
brelse(es->bh[i]);
+
+ if (IS_DYNAMIC_ES(es))
+ kfree(es->bh);
+
kfree(es);
return err;
}
@@ -847,6 +851,7 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
/* byte offset in sector */
off = EXFAT_BLK_OFFSET(byte_offset, sb);
es->start_off = off;
+ es->bh = es->__bh;
/* sector offset in cluster */
sec = EXFAT_B_TO_BLK(byte_offset, sb);
@@ -866,6 +871,16 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
es->num_entries = num_entries;
num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb);
+ if (num_bh > ARRAY_SIZE(es->__bh)) {
+ es->bh = kmalloc_array(num_bh, sizeof(*es->bh), GFP_KERNEL);
+ if (!es->bh) {
+ brelse(bh);
+ kfree(es);
+ return NULL;
+ }
+ es->bh[0] = bh;
+ }
+
for (i = 1; i < num_bh; i++) {
/* get the next sector */
if (exfat_is_last_sector_in_cluster(sbi, sec)) {
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index af55018ff22e..82395ae80dba 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -185,11 +185,14 @@ struct exfat_entry_set_cache {
struct super_block *sb;
unsigned int start_off;
int num_bh;
- struct buffer_head *bh[DIR_CACHE_SIZE];
+ struct buffer_head *__bh[DIR_CACHE_SIZE];
+ struct buffer_head **bh;
unsigned int num_entries;
bool modified;
};
+#define IS_DYNAMIC_ES(es) ((es)->__bh != (es)->bh)
+
struct exfat_dir_entry {
struct exfat_chain dir;
int entry;