jfs_discard.rar_range

#include <linux/fs.h> #include <linux/slab.h> #include <linux/blkdev.h> #include "jfs_incore.h" #include "jfs_superblock.h" #include "jfs_discard.h" #include "jfs_dmap.h" #include "jfs_debug.h" /* * NAME: jfs_issue_discard() * * FUNCTION: TRIM the specified block range on device, if supported * * PARAMETERS: * ip - pointer to in-core inode * blkno - starting block number to be trimmed (0..N) * nblocks - number of blocks to be trimmed * * RETURN VALUES: * none * * serialization: IREAD_LOCK(ipbmap) held on entry/exit; */ void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks) { struct super_block *sb = ip->i_sb; int r = 0; r = sb_issue_discard(sb, blkno, nblocks, GFP_NOFS, 0); if (unlikely(r != 0)) { jfs_err("JFS: sb_issue_discard" \ "(%p, %llu, %llu, GFP_NOFS, 0) = %d => failed!\n", sb, (unsigned long long)blkno, (unsigned long long)nblocks, r); } jfs_info("JFS: sb_issue_discard" \ "(%p, %llu, %llu, GFP_NOFS, 0) = %d\n", sb, (unsigned long long)blkno, (unsigned long long)nblocks, r); return; } /* * NAME: jfs_ioc_trim() * * FUNCTION: attempt to discard (TRIM) all free blocks from the * filesystem. * * PARAMETERS: * ip - pointer to in-core inode; * range - the range, given by user space * * RETURN VALUES: * 0 - success * -EIO - i/o error */ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range) { struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap; struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap; struct super_block *sb = ipbmap->i_sb; int agno, agno_end; u64 start, end, minlen; u64 trimmed = 0; /** * convert byte values to block size of filesystem: * start: First Byte to trim * len: number of Bytes to trim from start * minlen: minimum extent length in Bytes */ start = range->start >> sb->s_blocksize_bits; end = start + (range->len >> sb->s_blocksize_bits) - 1; minlen = range->minlen >> sb->s_blocksize_bits; if (minlen == 0) minlen = 1; if (minlen > bmp->db_agsize || start >= bmp->db_mapsize || range->len < sb->s_blocksize) return -EINVAL; if (end >= bmp->db_mapsize) end = bmp->db_mapsize - 1; /** * we trim all ag's within the range */ agno = BLKTOAG(start, JFS_SBI(ip->i_sb)); agno_end = BLKTOAG(end, JFS_SBI(ip->i_sb)); while (agno <= agno_end) { trimmed += dbDiscardAG(ip, agno, minlen); agno++; } range->len = trimmed << sb->s_blocksize_bits; return 0; }