1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *   Copyright (C) Tino Reichardt, 2012
4 */
5
6#include <linux/fs.h>
7#include <linux/slab.h>
8#include <linux/blkdev.h>
9
10#include "jfs_incore.h"
11#include "jfs_superblock.h"
12#include "jfs_discard.h"
13#include "jfs_dmap.h"
14#include "jfs_debug.h"
15
16
17/*
18 * NAME:	jfs_issue_discard()
19 *
20 * FUNCTION:	TRIM the specified block range on device, if supported
21 *
22 * PARAMETERS:
23 *	ip	- pointer to in-core inode
24 *	blkno	- starting block number to be trimmed (0..N)
25 *	nblocks	- number of blocks to be trimmed
26 *
27 * RETURN VALUES:
28 *	none
29 *
30 * serialization: IREAD_LOCK(ipbmap) held on entry/exit;
31 */
32void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks)
33{
34	struct super_block *sb = ip->i_sb;
35	int r = 0;
36
37	r = sb_issue_discard(sb, blkno, nblocks, GFP_NOFS, 0);
38	if (unlikely(r != 0)) {
39		jfs_err("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d => failed!",
40			sb, (unsigned long long)blkno,
41			(unsigned long long)nblocks, r);
42	}
43
44	jfs_info("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d",
45		sb, (unsigned long long)blkno,
46		(unsigned long long)nblocks, r);
47
48	return;
49}
50
51/*
52 * NAME:	jfs_ioc_trim()
53 *
54 * FUNCTION:	attempt to discard (TRIM) all free blocks from the
55 *              filesystem.
56 *
57 * PARAMETERS:
58 *	ip	- pointer to in-core inode;
59 *	range	- the range, given by user space
60 *
61 * RETURN VALUES:
62 *	0	- success
63 *	-EIO	- i/o error
64 */
65int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
66{
67	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
68	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
69	struct super_block *sb = ipbmap->i_sb;
70	int agno, agno_end;
71	u64 start, end, minlen;
72	u64 trimmed = 0;
73
74	/**
75	 * convert byte values to block size of filesystem:
76	 * start:	First Byte to trim
77	 * len:		number of Bytes to trim from start
78	 * minlen:	minimum extent length in Bytes
79	 */
80	start = range->start >> sb->s_blocksize_bits;
81	end = start + (range->len >> sb->s_blocksize_bits) - 1;
82	minlen = range->minlen >> sb->s_blocksize_bits;
83	if (minlen == 0)
84		minlen = 1;
85
86	if (minlen > bmp->db_agsize ||
87	    start >= bmp->db_mapsize ||
88	    range->len < sb->s_blocksize)
89		return -EINVAL;
90
91	if (end >= bmp->db_mapsize)
92		end = bmp->db_mapsize - 1;
93
94	/**
95	 * we trim all ag's within the range
96	 */
97	agno = BLKTOAG(start, JFS_SBI(ip->i_sb));
98	agno_end = BLKTOAG(end, JFS_SBI(ip->i_sb));
99	while (agno <= agno_end) {
100		trimmed += dbDiscardAG(ip, agno, minlen);
101		agno++;
102	}
103	range->len = trimmed << sb->s_blocksize_bits;
104
105	return 0;
106}
107