fs/jfs/jfs_discard.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  *   Copyright (C) Tino Reichardt, 2012
0004  */
0005
0006 #include <linux/fs.h>
0007 #include <linux/slab.h>
0008 #include <linux/blkdev.h>
0009
0010 #include "jfs_incore.h"
0011 #include "jfs_superblock.h"
0012 #include "jfs_discard.h"
0013 #include "jfs_dmap.h"
0014 #include "jfs_debug.h"
0015
0016
0017 /*
0018  * NAME:    jfs_issue_discard()
0019  *
0020  * FUNCTION:    TRIM the specified block range on device, if supported
0021  *
0022  * PARAMETERS:
0023  *  ip  - pointer to in-core inode
0024  *  blkno   - starting block number to be trimmed (0..N)
0025  *  nblocks - number of blocks to be trimmed
0026  *
0027  * RETURN VALUES:
0028  *  none
0029  *
0030  * serialization: IREAD_LOCK(ipbmap) held on entry/exit;
0031  */
0032 void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks)
0033 {
0034     struct super_block *sb = ip->i_sb;
0035     int r = 0;
0036
0037     r = sb_issue_discard(sb, blkno, nblocks, GFP_NOFS, 0);
0038     if (unlikely(r != 0)) {
0039         jfs_err("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d => failed!",
0040             sb, (unsigned long long)blkno,
0041             (unsigned long long)nblocks, r);
0042     }
0043
0044     jfs_info("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d",
0045         sb, (unsigned long long)blkno,
0046         (unsigned long long)nblocks, r);
0047
0048     return;
0049 }
0050
0051 /*
0052  * NAME:    jfs_ioc_trim()
0053  *
0054  * FUNCTION:    attempt to discard (TRIM) all free blocks from the
0055  *              filesystem.
0056  *
0057  * PARAMETERS:
0058  *  ip  - pointer to in-core inode;
0059  *  range   - the range, given by user space
0060  *
0061  * RETURN VALUES:
0062  *  0   - success
0063  *  -EIO    - i/o error
0064  */
0065 int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
0066 {
0067     struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
0068     struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
0069     struct super_block *sb = ipbmap->i_sb;
0070     int agno, agno_end;
0071     u64 start, end, minlen;
0072     u64 trimmed = 0;
0073
0074     /**
0075      * convert byte values to block size of filesystem:
0076      * start:   First Byte to trim
0077      * len:     number of Bytes to trim from start
0078      * minlen:  minimum extent length in Bytes
0079      */
0080     start = range->start >> sb->s_blocksize_bits;
0081     end = start + (range->len >> sb->s_blocksize_bits) - 1;
0082     minlen = range->minlen >> sb->s_blocksize_bits;
0083     if (minlen == 0)
0084         minlen = 1;
0085
0086     if (minlen > bmp->db_agsize ||
0087         start >= bmp->db_mapsize ||
0088         range->len < sb->s_blocksize)
0089         return -EINVAL;
0090
0091     if (end >= bmp->db_mapsize)
0092         end = bmp->db_mapsize - 1;
0093
0094     /**
0095      * we trim all ag's within the range
0096      */
0097     agno = BLKTOAG(start, JFS_SBI(ip->i_sb));
0098     agno_end = BLKTOAG(end, JFS_SBI(ip->i_sb));
0099     while (agno <= agno_end) {
0100         trimmed += dbDiscardAG(ip, agno, minlen);
0101         agno++;
0102     }
0103     range->len = trimmed << sb->s_blocksize_bits;
0104
0105     return 0;
0106 }