Merge tag 'exfat-for-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat

Pull exfat updates from Namjae Jeon:

 - Fix random stack corruption and incorrect error returns in
   exfat_get_block()

 - Optimize exfat_get_block() by improving checking corner cases

 - Fix an endless loop by self-linked chain in exfat_find_last_cluster

 - Remove dead EXFAT_CLUSTERS_UNTRACKED codes

 - Add missing shutdown check

 - Improve the delete performance with discard mount option

* tag 'exfat-for-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: call bh_read in get_block only when necessary
  exfat: fix potential wrong error return from get_block
  exfat: fix missing shutdown check
  exfat: fix the infinite loop in exfat_find_last_cluster()
  exfat: fix random stack corruption after get_block
  exfat: remove count used cluster from exfat_statfs()
  exfat: support batch discard of clusters when freeing clusters

1 files changed, 30 insertions, 1 deletions

diff --git a/fs/exfat/fatent.c b/fs/exfat/fatent.c
index 6f3651c6ca91..23065f948ae7 100644
--- a/fs/exfat/fatent.c
+++ b/fs/exfat/fatent.c
@@ -144,6 +144,20 @@ int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
 	return 0;
 }
 
+static inline void exfat_discard_cluster(struct super_block *sb,
+		unsigned int clu, unsigned int num_clusters)
+{
+	int ret;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+	ret = sb_issue_discard(sb, exfat_cluster_to_sector(sbi, clu),
+			sbi->sect_per_clus * num_clusters, GFP_NOFS, 0);
+	if (ret == -EOPNOTSUPP) {
+		exfat_err(sb, "discard not supported by device, disabling");
+		sbi->options.discard = 0;
+	}
+}
+
 /* This function must be called with bitmap_lock held */
 static int __exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain)
 {
@@ -196,7 +210,12 @@ static int __exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain
 			clu++;
 			num_clusters++;
 		} while (num_clusters < p_chain->size);
+
+		if (sbi->options.discard)
+			exfat_discard_cluster(sb, p_chain->dir, p_chain->size);
 	} else {
+		unsigned int nr_clu = 1;
+
 		do {
 			bool sync = false;
 			unsigned int n_clu = clu;
@@ -215,6 +234,16 @@ static int __exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain
 
 			if (exfat_clear_bitmap(inode, clu, (sync && IS_DIRSYNC(inode))))
 				break;
+
+			if (sbi->options.discard) {
+				if (n_clu == clu + 1)
+					nr_clu++;
+				else {
+					exfat_discard_cluster(sb, clu - nr_clu + 1, nr_clu);
+					nr_clu = 1;
+				}
+			}
+
 			clu = n_clu;
 			num_clusters++;
 
@@ -265,7 +294,7 @@ int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
 		clu = next;
 		if (exfat_ent_get(sb, clu, &next))
 			return -EIO;
-	} while (next != EXFAT_EOF_CLUSTER);
+	} while (next != EXFAT_EOF_CLUSTER && count <= p_chain->size);
 
 	if (p_chain->size != count) {
 		exfat_fs_error(sb,