add FITRIM ioctl to support trimming mounted filesystem
Signed-off-by: Hyeongseok Kim <[email protected]>
---
fs/exfat/balloc.c | 81 +++++++++++++++++++++++++++++++++++++++++++++
fs/exfat/exfat_fs.h | 1 +
fs/exfat/file.c | 33 ++++++++++++++++++
3 files changed, 115 insertions(+)
diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c
index 761c79c3a4ba..d47beef66892 100644
--- a/fs/exfat/balloc.c
+++ b/fs/exfat/balloc.c
@@ -273,3 +273,84 @@ int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count)
*ret_count = count;
return 0;
}
+
+int exfat_trim_fs(struct inode *inode, struct fstrim_range *range)
+{
+ unsigned int trim_begin, trim_end, count, next_free_clu;
+ u64 clu_start, clu_end, trim_minlen, trimmed_total = 0;
+ struct super_block *sb = inode->i_sb;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ int err = 0;
+
+ clu_start = max_t(u64, range->start >> sbi->cluster_size_bits,
+ EXFAT_FIRST_CLUSTER);
+ clu_end = clu_start + (range->len >> sbi->cluster_size_bits) - 1;
+ trim_minlen = range->minlen >> sbi->cluster_size_bits;
+
+ if (clu_start >= sbi->num_clusters || range->len < sbi->cluster_size)
+ return -EINVAL;
+
+ if (clu_end >= sbi->num_clusters)
+ clu_end = sbi->num_clusters - 1;
+
+ mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
+
+ trim_begin = trim_end = exfat_find_free_bitmap(sb, clu_start);
+ if (trim_begin == EXFAT_EOF_CLUSTER)
+ goto unlock;
+
+ next_free_clu = exfat_find_free_bitmap(sb, trim_end + 1);
+ if (next_free_clu == EXFAT_EOF_CLUSTER)
+ goto unlock;
+
+ do {
+ if (next_free_clu == trim_end + 1)
+ /* extend trim range for continuous free cluster */
+ trim_end++;
+ else {
+ /* trim current range if it's larger than trim_minlen */
+ count = trim_end - trim_begin + 1;
+ if (count >= trim_minlen) {
+ err = sb_issue_discard(sb,
+ exfat_cluster_to_sector(sbi, trim_begin),
+ count * sbi->sect_per_clus, GFP_NOFS, 0);
+ if (err)
+ goto unlock;
+
+ trimmed_total += count;
+ }
+
+ /* set next start point of the free hole */
+ trim_begin = trim_end = next_free_clu;
+ }
+
+ if (next_free_clu >= clu_end)
+ break;
+
+ if (fatal_signal_pending(current)) {
+ err = -ERESTARTSYS;
+ goto unlock;
+ }
+
+ next_free_clu = exfat_find_free_bitmap(sb, next_free_clu + 1);
+
+ } while (next_free_clu != EXFAT_EOF_CLUSTER &&
+ next_free_clu > trim_end);
+
+ /* try to trim remainder */
+ count = trim_end - trim_begin + 1;
+ if (count >= trim_minlen) {
+ err = sb_issue_discard(sb, exfat_cluster_to_sector(sbi, trim_begin),
+ count * sbi->sect_per_clus, GFP_NOFS, 0);
+ if (err)
+ goto unlock;
+
+ trimmed_total += count;
+ }
+
+unlock:
+ mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
+ range->len = trimmed_total << sbi->cluster_size_bits;
+
+ return err;
+}
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index a183021ae31d..e050aea0b639 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -411,6 +411,7 @@ int exfat_set_bitmap(struct inode *inode, unsigned int clu);
void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync);
unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu);
int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
+int exfat_trim_fs(struct inode *inode, struct fstrim_range *range);
/* file.c */
extern const struct file_operations exfat_file_operations;
diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index 679828e7be07..0cbad1577841 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -349,9 +349,42 @@ int exfat_setattr(struct dentry *dentry, struct iattr *attr)
return error;
}
+static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg)
+{
+ struct super_block *sb = inode->i_sb;
+ struct request_queue *q = bdev_get_queue(sb->s_bdev);
+ struct fstrim_range range;
+ int ret = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!blk_queue_discard(q))
+ return -EOPNOTSUPP;
+
+ if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range)))
+ return -EFAULT;
+
+ range.minlen = max_t(unsigned int, range.minlen,
+ q->limits.discard_granularity);
+
+ ret = exfat_trim_fs(inode, &range);
+ if (ret < 0)
+ return ret;
+
+ if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range)))
+ return -EFAULT;
+
+ return 0;
+}
+
long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
+ struct inode *inode = file_inode(filp);
+
switch (cmd) {
+ case FITRIM:
+ return exfat_ioctl_fitrim(inode, arg);
default:
return -ENOTTY;
}
--
2.27.0.83.g0313f36
On 2/17/21 8:56 AM, Chaitanya Kulkarni wrote:
> On 2/16/21 14:36, Hyeongseok Kim wrote:
>> +static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg)
>> +{
>> + struct super_block *sb = inode->i_sb;
> Do you really need sb variable ? it is only used once if I'm not wrong.
I got it. You're right.
>> + struct request_queue *q = bdev_get_queue(sb->s_bdev);
>> + struct fstrim_range range;
>> + int ret = 0;
>
On 2/16/21 14:36, Hyeongseok Kim wrote:
> +static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg)
> +{
> + struct super_block *sb = inode->i_sb;
Do you really need sb variable ? it is only used once if I'm not wrong.
> + struct request_queue *q = bdev_get_queue(sb->s_bdev);
> + struct fstrim_range range;
> + int ret = 0;