diff options
| -rw-r--r-- | fs/nilfs2/ioctl.c | 34 | ||||
| -rw-r--r-- | fs/nilfs2/sufile.c | 73 | ||||
| -rw-r--r-- | fs/nilfs2/sufile.h | 1 | ||||
| -rw-r--r-- | include/linux/nilfs2_fs.h | 2 |
4 files changed, 100 insertions, 10 deletions
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c index f2469ba6246b..6f617773a7f7 100644 --- a/fs/nilfs2/ioctl.c +++ b/fs/nilfs2/ioctl.c @@ -698,6 +698,38 @@ static int nilfs_ioctl_sync(struct inode *inode, struct file *filp, return 0; } +static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp) +{ + struct the_nilfs *nilfs = inode->i_sb->s_fs_info; + __u64 range[2]; + __u64 minseg, maxseg; + unsigned long segbytes; + int ret = -EPERM; + + if (!capable(CAP_SYS_ADMIN)) + goto out; + + ret = -EFAULT; + if (copy_from_user(range, argp, sizeof(__u64[2]))) + goto out; + + ret = -ERANGE; + if (range[1] > i_size_read(inode->i_sb->s_bdev->bd_inode)) + goto out; + + segbytes = nilfs->ns_blocks_per_segment * nilfs->ns_blocksize; + + minseg = range[0] + segbytes - 1; + do_div(minseg, segbytes); + maxseg = NILFS_SB2_OFFSET_BYTES(range[1]); + do_div(maxseg, segbytes); + maxseg--; + + ret = nilfs_sufile_set_alloc_range(nilfs->ns_sufile, minseg, maxseg); +out: + return ret; +} + static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp, unsigned int cmd, void __user *argp, size_t membsz, @@ -763,6 +795,8 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return nilfs_ioctl_clean_segments(inode, filp, cmd, argp); case NILFS_IOCTL_SYNC: return nilfs_ioctl_sync(inode, filp, cmd, argp); + case NILFS_IOCTL_SET_ALLOC_RANGE: + return nilfs_ioctl_set_alloc_range(inode, argp); default: return -ENOTTY; } diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c index 1d6f488ccae8..f4374df00ad5 100644 --- a/fs/nilfs2/sufile.c +++ b/fs/nilfs2/sufile.c @@ -33,7 +33,9 @@ struct nilfs_sufile_info { struct nilfs_mdt_info mi; - unsigned long ncleansegs; + unsigned long ncleansegs;/* number of clean segments */ + __u64 allocmin; /* lower limit of allocatable segment range */ + __u64 allocmax; /* upper limit of allocatable segment range */ }; static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile) @@ -248,6 +250,35 @@ int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create, } /** + * nilfs_sufile_set_alloc_range - limit range of segment to be allocated + * @sufile: inode of segment usage file + * @start: minimum segment number of allocatable region (inclusive) + * @end: maximum segment number of allocatable region (inclusive) + * + * Return Value: On success, 0 is returned. On error, one of the + * following negative error codes is returned. + * + * %-ERANGE - invalid segment region + */ +int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end) +{ + struct nilfs_sufile_info *sui = NILFS_SUI(sufile); + __u64 nsegs; + int ret = -ERANGE; + + down_write(&NILFS_MDT(sufile)->mi_sem); + nsegs = nilfs_sufile_get_nsegments(sufile); + + if (start <= end && end < nsegs) { + sui->allocmin = start; + sui->allocmax = end; + ret = 0; + } + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** * nilfs_sufile_alloc - allocate a segment * @sufile: inode of segment usage file * @segnump: pointer to segment number @@ -269,11 +300,12 @@ int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump) struct buffer_head *header_bh, *su_bh; struct nilfs_sufile_header *header; struct nilfs_segment_usage *su; + struct nilfs_sufile_info *sui = NILFS_SUI(sufile); size_t susz = NILFS_MDT(sufile)->mi_entry_size; __u64 segnum, maxsegnum, last_alloc; void *kaddr; - unsigned long nsegments, ncleansegs, nsus; - int ret, i, j; + unsigned long nsegments, ncleansegs, nsus, cnt; + int ret, j; down_write(&NILFS_MDT(sufile)->mi_sem); @@ -287,13 +319,31 @@ int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump) kunmap_atomic(kaddr, KM_USER0); nsegments = nilfs_sufile_get_nsegments(sufile); + maxsegnum = sui->allocmax; segnum = last_alloc + 1; - maxsegnum = nsegments - 1; - for (i = 0; i < nsegments; i += nsus) { - if (segnum >= nsegments) { - /* wrap around */ - segnum = 0; - maxsegnum = last_alloc; + if (segnum < sui->allocmin || segnum > sui->allocmax) + segnum = sui->allocmin; + + for (cnt = 0; cnt < nsegments; cnt += nsus) { + if (segnum > maxsegnum) { + if (cnt < sui->allocmax - sui->allocmin + 1) { + /* + * wrap around in the limited region. + * if allocation started from + * sui->allocmin, this never happens. + */ + segnum = sui->allocmin; + maxsegnum = last_alloc; + } else if (segnum > sui->allocmin && + sui->allocmax + 1 < nsegments) { + segnum = sui->allocmax + 1; + maxsegnum = nsegments - 1; + } else if (sui->allocmin > 0) { + segnum = 0; + maxsegnum = sui->allocmin - 1; + } else { + break; /* never happens */ + } } ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1, &su_bh); @@ -319,7 +369,7 @@ int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump) header->sh_last_alloc = cpu_to_le64(segnum); kunmap_atomic(kaddr, KM_USER0); - NILFS_SUI(sufile)->ncleansegs--; + sui->ncleansegs--; nilfs_mdt_mark_buffer_dirty(header_bh); nilfs_mdt_mark_buffer_dirty(su_bh); nilfs_mdt_mark_dirty(sufile); @@ -679,6 +729,9 @@ int nilfs_sufile_read(struct super_block *sb, size_t susize, kunmap_atomic(kaddr, KM_USER0); brelse(header_bh); + sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1; + sui->allocmin = 0; + unlock_new_inode(sufile); out: *inodep = sufile; diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h index a943fbacb45b..57bfee9cd02d 100644 --- a/fs/nilfs2/sufile.h +++ b/fs/nilfs2/sufile.h @@ -36,6 +36,7 @@ static inline unsigned long nilfs_sufile_get_nsegments(struct inode *sufile) unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile); +int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end); int nilfs_sufile_alloc(struct inode *, __u64 *); int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum); int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum, diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h index bd8678f8a421..7454ad7451b4 100644 --- a/include/linux/nilfs2_fs.h +++ b/include/linux/nilfs2_fs.h @@ -845,5 +845,7 @@ struct nilfs_bdesc { _IOR(NILFS_IOCTL_IDENT, 0x8A, __u64) #define NILFS_IOCTL_RESIZE \ _IOW(NILFS_IOCTL_IDENT, 0x8B, __u64) +#define NILFS_IOCTL_SET_ALLOC_RANGE \ + _IOW(NILFS_IOCTL_IDENT, 0x8C, __u64[2]) #endif /* _LINUX_NILFS_FS_H */ |