diff options
Diffstat (limited to 'fs/nilfs2/sufile.c')
| -rw-r--r-- | fs/nilfs2/sufile.c | 1260 |
1 files changed, 1260 insertions, 0 deletions
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c new file mode 100644 index 000000000..58ca7c936 --- /dev/null +++ b/fs/nilfs2/sufile.c @@ -0,0 +1,1260 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * NILFS segment usage file. + * + * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. + * + * Written by Koji Sato. + * Revised by Ryusuke Konishi. + */ + +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/buffer_head.h> +#include <linux/errno.h> +#include "mdt.h" +#include "sufile.h" + +#include <trace/events/nilfs2.h> + +/** + * struct nilfs_sufile_info - on-memory private data of sufile + * @mi: on-memory private data of metadata file + * @ncleansegs: number of clean segments + * @allocmin: lower limit of allocatable segment range + * @allocmax: upper limit of allocatable segment range + */ +struct nilfs_sufile_info { + struct nilfs_mdt_info mi; + 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) +{ + return (struct nilfs_sufile_info *)NILFS_MDT(sufile); +} + +static inline unsigned long +nilfs_sufile_segment_usages_per_block(const struct inode *sufile) +{ + return NILFS_MDT(sufile)->mi_entries_per_block; +} + +static unsigned long +nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum) +{ + __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset; + + do_div(t, nilfs_sufile_segment_usages_per_block(sufile)); + return (unsigned long)t; +} + +static unsigned long +nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum) +{ + __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset; + + return do_div(t, nilfs_sufile_segment_usages_per_block(sufile)); +} + +static unsigned long +nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr, + __u64 max) +{ + return min_t(unsigned long, + nilfs_sufile_segment_usages_per_block(sufile) - + nilfs_sufile_get_offset(sufile, curr), + max - curr + 1); +} + +static struct nilfs_segment_usage * +nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum, + struct buffer_head *bh, void *kaddr) +{ + return kaddr + bh_offset(bh) + + nilfs_sufile_get_offset(sufile, segnum) * + NILFS_MDT(sufile)->mi_entry_size; +} + +static inline int nilfs_sufile_get_header_block(struct inode *sufile, + struct buffer_head **bhp) +{ + return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp); +} + +static inline int +nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum, + int create, struct buffer_head **bhp) +{ + return nilfs_mdt_get_block(sufile, + nilfs_sufile_get_blkoff(sufile, segnum), + create, NULL, bhp); +} + +static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile, + __u64 segnum) +{ + return nilfs_mdt_delete_block(sufile, + nilfs_sufile_get_blkoff(sufile, segnum)); +} + +static void nilfs_sufile_mod_counter(struct buffer_head *header_bh, + u64 ncleanadd, u64 ndirtyadd) +{ + struct nilfs_sufile_header *header; + void *kaddr; + + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + le64_add_cpu(&header->sh_ncleansegs, ncleanadd); + le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd); + kunmap_atomic(kaddr); + + mark_buffer_dirty(header_bh); +} + +/** + * nilfs_sufile_get_ncleansegs - return the number of clean segments + * @sufile: inode of segment usage file + */ +unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile) +{ + return NILFS_SUI(sufile)->ncleansegs; +} + +/** + * nilfs_sufile_updatev - modify multiple segment usages at a time + * @sufile: inode of segment usage file + * @segnumv: array of segment numbers + * @nsegs: size of @segnumv array + * @create: creation flag + * @ndone: place to store number of modified segments on @segnumv + * @dofunc: primitive operation for the update + * + * Description: nilfs_sufile_updatev() repeatedly calls @dofunc + * against the given array of segments. The @dofunc is called with + * buffers of a header block and the sufile block in which the target + * segment usage entry is contained. If @ndone is given, the number + * of successfully modified segments from the head is stored in the + * place @ndone points to. + * + * Return Value: On success, zero is returned. On error, one of the + * following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-ENOENT - Given segment usage is in hole block (may be returned if + * @create is zero) + * + * %-EINVAL - Invalid segment usage number + */ +int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs, + int create, size_t *ndone, + void (*dofunc)(struct inode *, __u64, + struct buffer_head *, + struct buffer_head *)) +{ + struct buffer_head *header_bh, *bh; + unsigned long blkoff, prev_blkoff; + __u64 *seg; + size_t nerr = 0, n = 0; + int ret = 0; + + if (unlikely(nsegs == 0)) + goto out; + + down_write(&NILFS_MDT(sufile)->mi_sem); + for (seg = segnumv; seg < segnumv + nsegs; seg++) { + if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) { + nilfs_warn(sufile->i_sb, + "%s: invalid segment number: %llu", + __func__, (unsigned long long)*seg); + nerr++; + } + } + if (nerr > 0) { + ret = -EINVAL; + goto out_sem; + } + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out_sem; + + seg = segnumv; + blkoff = nilfs_sufile_get_blkoff(sufile, *seg); + ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh); + if (ret < 0) + goto out_header; + + for (;;) { + dofunc(sufile, *seg, header_bh, bh); + + if (++seg >= segnumv + nsegs) + break; + prev_blkoff = blkoff; + blkoff = nilfs_sufile_get_blkoff(sufile, *seg); + if (blkoff == prev_blkoff) + continue; + + /* get different block */ + brelse(bh); + ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh); + if (unlikely(ret < 0)) + goto out_header; + } + brelse(bh); + + out_header: + n = seg - segnumv; + brelse(header_bh); + out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + out: + if (ndone) + *ndone = n; + return ret; +} + +int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create, + void (*dofunc)(struct inode *, __u64, + struct buffer_head *, + struct buffer_head *)) +{ + struct buffer_head *header_bh, *bh; + int ret; + + if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) { + nilfs_warn(sufile->i_sb, "%s: invalid segment number: %llu", + __func__, (unsigned long long)segnum); + return -EINVAL; + } + down_write(&NILFS_MDT(sufile)->mi_sem); + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out_sem; + + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh); + if (!ret) { + dofunc(sufile, segnum, header_bh, bh); + brelse(bh); + } + brelse(header_bh); + + out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * 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 + * + * Description: nilfs_sufile_alloc() allocates a clean segment. + * + * Return Value: On success, 0 is returned and the segment number of the + * allocated segment is stored in the place pointed by @segnump. On error, one + * of the following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-ENOSPC - No clean segment left. + */ +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, nsus, cnt; + int ret, j; + + down_write(&NILFS_MDT(sufile)->mi_sem); + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out_sem; + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + last_alloc = le64_to_cpu(header->sh_last_alloc); + kunmap_atomic(kaddr); + + nsegments = nilfs_sufile_get_nsegments(sufile); + maxsegnum = sui->allocmax; + segnum = last_alloc + 1; + 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 */ + } + } + trace_nilfs2_segment_usage_check(sufile, segnum, cnt); + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1, + &su_bh); + if (ret < 0) + goto out_header; + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage( + sufile, segnum, su_bh, kaddr); + + nsus = nilfs_sufile_segment_usages_in_block( + sufile, segnum, maxsegnum); + for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) { + if (!nilfs_segment_usage_clean(su)) + continue; + /* found a clean segment */ + nilfs_segment_usage_set_dirty(su); + kunmap_atomic(kaddr); + + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + le64_add_cpu(&header->sh_ncleansegs, -1); + le64_add_cpu(&header->sh_ndirtysegs, 1); + header->sh_last_alloc = cpu_to_le64(segnum); + kunmap_atomic(kaddr); + + sui->ncleansegs--; + mark_buffer_dirty(header_bh); + mark_buffer_dirty(su_bh); + nilfs_mdt_mark_dirty(sufile); + brelse(su_bh); + *segnump = segnum; + + trace_nilfs2_segment_usage_allocated(sufile, segnum); + + goto out_header; + } + + kunmap_atomic(kaddr); + brelse(su_bh); + } + + /* no segments left */ + ret = -ENOSPC; + + out_header: + brelse(header_bh); + + out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum, + struct buffer_head *header_bh, + struct buffer_head *su_bh) +{ + struct nilfs_segment_usage *su; + void *kaddr; + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); + if (unlikely(!nilfs_segment_usage_clean(su))) { + nilfs_warn(sufile->i_sb, "%s: segment %llu must be clean", + __func__, (unsigned long long)segnum); + kunmap_atomic(kaddr); + return; + } + nilfs_segment_usage_set_dirty(su); + kunmap_atomic(kaddr); + + nilfs_sufile_mod_counter(header_bh, -1, 1); + NILFS_SUI(sufile)->ncleansegs--; + + mark_buffer_dirty(su_bh); + nilfs_mdt_mark_dirty(sufile); +} + +void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum, + struct buffer_head *header_bh, + struct buffer_head *su_bh) +{ + struct nilfs_segment_usage *su; + void *kaddr; + int clean, dirty; + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); + if (su->su_flags == cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)) && + su->su_nblocks == cpu_to_le32(0)) { + kunmap_atomic(kaddr); + return; + } + clean = nilfs_segment_usage_clean(su); + dirty = nilfs_segment_usage_dirty(su); + + /* make the segment garbage */ + su->su_lastmod = cpu_to_le64(0); + su->su_nblocks = cpu_to_le32(0); + su->su_flags = cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)); + kunmap_atomic(kaddr); + + nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1); + NILFS_SUI(sufile)->ncleansegs -= clean; + + mark_buffer_dirty(su_bh); + nilfs_mdt_mark_dirty(sufile); +} + +void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum, + struct buffer_head *header_bh, + struct buffer_head *su_bh) +{ + struct nilfs_segment_usage *su; + void *kaddr; + int sudirty; + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); + if (nilfs_segment_usage_clean(su)) { + nilfs_warn(sufile->i_sb, "%s: segment %llu is already clean", + __func__, (unsigned long long)segnum); + kunmap_atomic(kaddr); + return; + } + WARN_ON(nilfs_segment_usage_error(su)); + WARN_ON(!nilfs_segment_usage_dirty(su)); + + sudirty = nilfs_segment_usage_dirty(su); + nilfs_segment_usage_set_clean(su); + kunmap_atomic(kaddr); + mark_buffer_dirty(su_bh); + + nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0); + NILFS_SUI(sufile)->ncleansegs++; + + nilfs_mdt_mark_dirty(sufile); + + trace_nilfs2_segment_usage_freed(sufile, segnum); +} + +/** + * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty + * @sufile: inode of segment usage file + * @segnum: segment number + */ +int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum) +{ + struct buffer_head *bh; + void *kaddr; + struct nilfs_segment_usage *su; + int ret; + + down_write(&NILFS_MDT(sufile)->mi_sem); + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh); + if (ret) + goto out_sem; + + kaddr = kmap_atomic(bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr); + if (unlikely(nilfs_segment_usage_error(su))) { + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + + kunmap_atomic(kaddr); + brelse(bh); + if (nilfs_segment_is_active(nilfs, segnum)) { + nilfs_error(sufile->i_sb, + "active segment %llu is erroneous", + (unsigned long long)segnum); + } else { + /* + * Segments marked erroneous are never allocated by + * nilfs_sufile_alloc(); only active segments, ie, + * the segments indexed by ns_segnum or ns_nextnum, + * can be erroneous here. + */ + WARN_ON_ONCE(1); + } + ret = -EIO; + } else { + nilfs_segment_usage_set_dirty(su); + kunmap_atomic(kaddr); + mark_buffer_dirty(bh); + nilfs_mdt_mark_dirty(sufile); + brelse(bh); + } +out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * nilfs_sufile_set_segment_usage - set usage of a segment + * @sufile: inode of segment usage file + * @segnum: segment number + * @nblocks: number of live blocks in the segment + * @modtime: modification time (option) + */ +int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum, + unsigned long nblocks, time64_t modtime) +{ + struct buffer_head *bh; + struct nilfs_segment_usage *su; + void *kaddr; + int ret; + + down_write(&NILFS_MDT(sufile)->mi_sem); + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh); + if (ret < 0) + goto out_sem; + + kaddr = kmap_atomic(bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr); + if (modtime) { + /* + * Check segusage error and set su_lastmod only when updating + * this entry with a valid timestamp, not for cancellation. + */ + WARN_ON_ONCE(nilfs_segment_usage_error(su)); + su->su_lastmod = cpu_to_le64(modtime); + } + su->su_nblocks = cpu_to_le32(nblocks); + kunmap_atomic(kaddr); + + mark_buffer_dirty(bh); + nilfs_mdt_mark_dirty(sufile); + brelse(bh); + + out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * nilfs_sufile_get_stat - get segment usage statistics + * @sufile: inode of segment usage file + * @sustat: pointer to a structure of segment usage statistics + * + * Description: nilfs_sufile_get_stat() returns information about segment + * usage. + * + * Return Value: On success, 0 is returned, and segment usage information is + * stored in the place pointed by @sustat. On error, one of the following + * negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + */ +int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat) +{ + struct buffer_head *header_bh; + struct nilfs_sufile_header *header; + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + void *kaddr; + int ret; + + down_read(&NILFS_MDT(sufile)->mi_sem); + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out_sem; + + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile); + sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs); + sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs); + sustat->ss_ctime = nilfs->ns_ctime; + sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime; + spin_lock(&nilfs->ns_last_segment_lock); + sustat->ss_prot_seq = nilfs->ns_prot_seq; + spin_unlock(&nilfs->ns_last_segment_lock); + kunmap_atomic(kaddr); + brelse(header_bh); + + out_sem: + up_read(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum, + struct buffer_head *header_bh, + struct buffer_head *su_bh) +{ + struct nilfs_segment_usage *su; + void *kaddr; + int suclean; + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); + if (nilfs_segment_usage_error(su)) { + kunmap_atomic(kaddr); + return; + } + suclean = nilfs_segment_usage_clean(su); + nilfs_segment_usage_set_error(su); + kunmap_atomic(kaddr); + + if (suclean) { + nilfs_sufile_mod_counter(header_bh, -1, 0); + NILFS_SUI(sufile)->ncleansegs--; + } + mark_buffer_dirty(su_bh); + nilfs_mdt_mark_dirty(sufile); +} + +/** + * nilfs_sufile_truncate_range - truncate range of segment array + * @sufile: inode of segment usage file + * @start: start segment number (inclusive) + * @end: end segment number (inclusive) + * + * Return Value: On success, 0 is returned. On error, one of the + * following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-EINVAL - Invalid number of segments specified + * + * %-EBUSY - Dirty or active segments are present in the range + */ +static int nilfs_sufile_truncate_range(struct inode *sufile, + __u64 start, __u64 end) +{ + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + struct buffer_head *header_bh; + struct buffer_head *su_bh; + struct nilfs_segment_usage *su, *su2; + size_t susz = NILFS_MDT(sufile)->mi_entry_size; + unsigned long segusages_per_block; + unsigned long nsegs, ncleaned; + __u64 segnum; + void *kaddr; + ssize_t n, nc; + int ret; + int j; + + nsegs = nilfs_sufile_get_nsegments(sufile); + + ret = -EINVAL; + if (start > end || start >= nsegs) + goto out; + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out; + + segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile); + ncleaned = 0; + + for (segnum = start; segnum <= end; segnum += n) { + n = min_t(unsigned long, + segusages_per_block - + nilfs_sufile_get_offset(sufile, segnum), + end - segnum + 1); + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, + &su_bh); + if (ret < 0) { + if (ret != -ENOENT) + goto out_header; + /* hole */ + continue; + } + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage( + sufile, segnum, su_bh, kaddr); + su2 = su; + for (j = 0; j < n; j++, su = (void *)su + susz) { + if ((le32_to_cpu(su->su_flags) & + ~BIT(NILFS_SEGMENT_USAGE_ERROR)) || + nilfs_segment_is_active(nilfs, segnum + j)) { + ret = -EBUSY; + kunmap_atomic(kaddr); + brelse(su_bh); + goto out_header; + } + } + nc = 0; + for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) { + if (nilfs_segment_usage_error(su)) { + nilfs_segment_usage_set_clean(su); + nc++; + } + } + kunmap_atomic(kaddr); + if (nc > 0) { + mark_buffer_dirty(su_bh); + ncleaned += nc; + } + brelse(su_bh); + + if (n == segusages_per_block) { + /* make hole */ + nilfs_sufile_delete_segment_usage_block(sufile, segnum); + } + } + ret = 0; + +out_header: + if (ncleaned > 0) { + NILFS_SUI(sufile)->ncleansegs += ncleaned; + nilfs_sufile_mod_counter(header_bh, ncleaned, 0); + nilfs_mdt_mark_dirty(sufile); + } + brelse(header_bh); +out: + return ret; +} + +/** + * nilfs_sufile_resize - resize segment array + * @sufile: inode of segment usage file + * @newnsegs: new number of segments + * + * Return Value: On success, 0 is returned. On error, one of the + * following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-ENOSPC - Enough free space is not left for shrinking + * + * %-EBUSY - Dirty or active segments exist in the region to be truncated + */ +int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs) +{ + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + struct buffer_head *header_bh; + struct nilfs_sufile_header *header; + struct nilfs_sufile_info *sui = NILFS_SUI(sufile); + void *kaddr; + unsigned long nsegs, nrsvsegs; + int ret = 0; + + down_write(&NILFS_MDT(sufile)->mi_sem); + + nsegs = nilfs_sufile_get_nsegments(sufile); + if (nsegs == newnsegs) + goto out; + + ret = -ENOSPC; + nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs); + if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs) + goto out; + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out; + + if (newnsegs > nsegs) { + sui->ncleansegs += newnsegs - nsegs; + } else /* newnsegs < nsegs */ { + ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1); + if (ret < 0) + goto out_header; + + sui->ncleansegs -= nsegs - newnsegs; + + /* + * If the sufile is successfully truncated, immediately adjust + * the segment allocation space while locking the semaphore + * "mi_sem" so that nilfs_sufile_alloc() never allocates + * segments in the truncated space. + */ + sui->allocmax = newnsegs - 1; + sui->allocmin = 0; + } + + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs); + kunmap_atomic(kaddr); + + mark_buffer_dirty(header_bh); + nilfs_mdt_mark_dirty(sufile); + nilfs_set_nsegments(nilfs, newnsegs); + +out_header: + brelse(header_bh); +out: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * nilfs_sufile_get_suinfo - + * @sufile: inode of segment usage file + * @segnum: segment number to start looking + * @buf: array of suinfo + * @sisz: byte size of suinfo + * @nsi: size of suinfo array + * + * Description: + * + * Return Value: On success, 0 is returned and .... On error, one of the + * following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + */ +ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf, + unsigned int sisz, size_t nsi) +{ + struct buffer_head *su_bh; + struct nilfs_segment_usage *su; + struct nilfs_suinfo *si = buf; + size_t susz = NILFS_MDT(sufile)->mi_entry_size; + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + void *kaddr; + unsigned long nsegs, segusages_per_block; + ssize_t n; + int ret, i, j; + + down_read(&NILFS_MDT(sufile)->mi_sem); + + segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile); + nsegs = min_t(unsigned long, + nilfs_sufile_get_nsegments(sufile) - segnum, + nsi); + for (i = 0; i < nsegs; i += n, segnum += n) { + n = min_t(unsigned long, + segusages_per_block - + nilfs_sufile_get_offset(sufile, segnum), + nsegs - i); + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, + &su_bh); + if (ret < 0) { + if (ret != -ENOENT) + goto out; + /* hole */ + memset(si, 0, sisz * n); + si = (void *)si + sisz * n; + continue; + } + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage( + sufile, segnum, su_bh, kaddr); + for (j = 0; j < n; + j++, su = (void *)su + susz, si = (void *)si + sisz) { + si->sui_lastmod = le64_to_cpu(su->su_lastmod); + si->sui_nblocks = le32_to_cpu(su->su_nblocks); + si->sui_flags = le32_to_cpu(su->su_flags) & + ~BIT(NILFS_SEGMENT_USAGE_ACTIVE); + if (nilfs_segment_is_active(nilfs, segnum + j)) + si->sui_flags |= + BIT(NILFS_SEGMENT_USAGE_ACTIVE); + } + kunmap_atomic(kaddr); + brelse(su_bh); + } + ret = nsegs; + + out: + up_read(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * nilfs_sufile_set_suinfo - sets segment usage info + * @sufile: inode of segment usage file + * @buf: array of suinfo_update + * @supsz: byte size of suinfo_update + * @nsup: size of suinfo_update array + * + * Description: Takes an array of nilfs_suinfo_update structs and updates + * segment usage accordingly. Only the fields indicated by the sup_flags + * are updated. + * + * Return Value: On success, 0 is returned. On error, one of the + * following negative error codes is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-EINVAL - Invalid values in input (segment number, flags or nblocks) + */ +ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf, + unsigned int supsz, size_t nsup) +{ + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + struct buffer_head *header_bh, *bh; + struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup; + struct nilfs_segment_usage *su; + void *kaddr; + unsigned long blkoff, prev_blkoff; + int cleansi, cleansu, dirtysi, dirtysu; + long ncleaned = 0, ndirtied = 0; + int ret = 0; + + if (unlikely(nsup == 0)) + return ret; + + for (sup = buf; sup < supend; sup = (void *)sup + supsz) { + if (sup->sup_segnum >= nilfs->ns_nsegments + || (sup->sup_flags & + (~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS)) + || (nilfs_suinfo_update_nblocks(sup) && + sup->sup_sui.sui_nblocks > + nilfs->ns_blocks_per_segment)) + return -EINVAL; + } + + down_write(&NILFS_MDT(sufile)->mi_sem); + + ret = nilfs_sufile_get_header_block(sufile, &header_bh); + if (ret < 0) + goto out_sem; + + sup = buf; + blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum); + ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh); + if (ret < 0) + goto out_header; + + for (;;) { + kaddr = kmap_atomic(bh->b_page); + su = nilfs_sufile_block_get_segment_usage( + sufile, sup->sup_segnum, bh, kaddr); + + if (nilfs_suinfo_update_lastmod(sup)) + su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod); + + if (nilfs_suinfo_update_nblocks(sup)) + su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks); + + if (nilfs_suinfo_update_flags(sup)) { + /* + * Active flag is a virtual flag projected by running + * nilfs kernel code - drop it not to write it to + * disk. + */ + sup->sup_sui.sui_flags &= + ~BIT(NILFS_SEGMENT_USAGE_ACTIVE); + + cleansi = nilfs_suinfo_clean(&sup->sup_sui); + cleansu = nilfs_segment_usage_clean(su); + dirtysi = nilfs_suinfo_dirty(&sup->sup_sui); + dirtysu = nilfs_segment_usage_dirty(su); + + if (cleansi && !cleansu) + ++ncleaned; + else if (!cleansi && cleansu) + --ncleaned; + + if (dirtysi && !dirtysu) + ++ndirtied; + else if (!dirtysi && dirtysu) + --ndirtied; + + su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags); + } + + kunmap_atomic(kaddr); + + sup = (void *)sup + supsz; + if (sup >= supend) + break; + + prev_blkoff = blkoff; + blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum); + if (blkoff == prev_blkoff) + continue; + + /* get different block */ + mark_buffer_dirty(bh); + put_bh(bh); + ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh); + if (unlikely(ret < 0)) + goto out_mark; + } + mark_buffer_dirty(bh); + put_bh(bh); + + out_mark: + if (ncleaned || ndirtied) { + nilfs_sufile_mod_counter(header_bh, (u64)ncleaned, + (u64)ndirtied); + NILFS_SUI(sufile)->ncleansegs += ncleaned; + } + nilfs_mdt_mark_dirty(sufile); + out_header: + put_bh(header_bh); + out_sem: + up_write(&NILFS_MDT(sufile)->mi_sem); + return ret; +} + +/** + * nilfs_sufile_trim_fs() - trim ioctl handle function + * @sufile: inode of segment usage file + * @range: fstrim_range structure + * + * start: First Byte to trim + * len: number of Bytes to trim from start + * minlen: minimum extent length in Bytes + * + * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes + * from start to start+len. start is rounded up to the next block boundary + * and start+len is rounded down. For each clean segment blkdev_issue_discard + * function is invoked. + * + * Return Value: On success, 0 is returned or negative error code, otherwise. + */ +int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range) +{ + struct the_nilfs *nilfs = sufile->i_sb->s_fs_info; + struct buffer_head *su_bh; + struct nilfs_segment_usage *su; + void *kaddr; + size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size; + sector_t seg_start, seg_end, start_block, end_block; + sector_t start = 0, nblocks = 0; + u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0; + int ret = 0; + unsigned int sects_per_block; + + sects_per_block = (1 << nilfs->ns_blocksize_bits) / + bdev_logical_block_size(nilfs->ns_bdev); + len = range->len >> nilfs->ns_blocksize_bits; + minlen = range->minlen >> nilfs->ns_blocksize_bits; + max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment); + + if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits) + return -EINVAL; + + start_block = (range->start + nilfs->ns_blocksize - 1) >> + nilfs->ns_blocksize_bits; + + /* + * range->len can be very large (actually, it is set to + * ULLONG_MAX by default) - truncate upper end of the range + * carefully so as not to overflow. + */ + if (max_blocks - start_block < len) + end_block = max_blocks - 1; + else + end_block = start_block + len - 1; + + segnum = nilfs_get_segnum_of_block(nilfs, start_block); + segnum_end = nilfs_get_segnum_of_block(nilfs, end_block); + + down_read(&NILFS_MDT(sufile)->mi_sem); + + while (segnum <= segnum_end) { + n = nilfs_sufile_segment_usages_in_block(sufile, segnum, + segnum_end); + + ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, + &su_bh); + if (ret < 0) { + if (ret != -ENOENT) + goto out_sem; + /* hole */ + segnum += n; + continue; + } + + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage(sufile, segnum, + su_bh, kaddr); + for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) { + if (!nilfs_segment_usage_clean(su)) + continue; + + nilfs_get_segment_range(nilfs, segnum, &seg_start, + &seg_end); + + if (!nblocks) { + /* start new extent */ + start = seg_start; + nblocks = seg_end - seg_start + 1; + continue; + } + + if (start + nblocks == seg_start) { + /* add to previous extent */ + nblocks += seg_end - seg_start + 1; + continue; + } + + /* discard previous extent */ + if (start < start_block) { + nblocks -= start_block - start; + start = start_block; + } + + if (nblocks >= minlen) { + kunmap_atomic(kaddr); + + ret = blkdev_issue_discard(nilfs->ns_bdev, + start * sects_per_block, + nblocks * sects_per_block, + GFP_NOFS); + if (ret < 0) { + put_bh(su_bh); + goto out_sem; + } + + ndiscarded += nblocks; + kaddr = kmap_atomic(su_bh->b_page); + su = nilfs_sufile_block_get_segment_usage( + sufile, segnum, su_bh, kaddr); + } + + /* start new extent */ + start = seg_start; + nblocks = seg_end - seg_start + 1; + } + kunmap_atomic(kaddr); + put_bh(su_bh); + } + + + if (nblocks) { + /* discard last extent */ + if (start < start_block) { + nblocks -= start_block - start; + start = start_block; + } + if (start + nblocks > end_block + 1) + nblocks = end_block - start + 1; + + if (nblocks >= minlen) { + ret = blkdev_issue_discard(nilfs->ns_bdev, + start * sects_per_block, + nblocks * sects_per_block, + GFP_NOFS); + if (!ret) + ndiscarded += nblocks; + } + } + +out_sem: + up_read(&NILFS_MDT(sufile)->mi_sem); + + range->len = ndiscarded << nilfs->ns_blocksize_bits; + return ret; +} + +/** + * nilfs_sufile_read - read or get sufile inode + * @sb: super block instance + * @susize: size of a segment usage entry + * @raw_inode: on-disk sufile inode + * @inodep: buffer to store the inode + */ +int nilfs_sufile_read(struct super_block *sb, size_t susize, + struct nilfs_inode *raw_inode, struct inode **inodep) +{ + struct inode *sufile; + struct nilfs_sufile_info *sui; + struct buffer_head *header_bh; + struct nilfs_sufile_header *header; + void *kaddr; + int err; + + if (susize > sb->s_blocksize) { + nilfs_err(sb, "too large segment usage size: %zu bytes", + susize); + return -EINVAL; + } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) { + nilfs_err(sb, "too small segment usage size: %zu bytes", + susize); + return -EINVAL; + } + + sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO); + if (unlikely(!sufile)) + return -ENOMEM; + if (!(sufile->i_state & I_NEW)) + goto out; + + err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui)); + if (err) + goto failed; + + nilfs_mdt_set_entry_size(sufile, susize, + sizeof(struct nilfs_sufile_header)); + + err = nilfs_read_inode_common(sufile, raw_inode); + if (err) + goto failed; + + err = nilfs_sufile_get_header_block(sufile, &header_bh); + if (err) + goto failed; + + sui = NILFS_SUI(sufile); + kaddr = kmap_atomic(header_bh->b_page); + header = kaddr + bh_offset(header_bh); + sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs); + kunmap_atomic(kaddr); + brelse(header_bh); + + sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1; + sui->allocmin = 0; + + unlock_new_inode(sufile); + out: + *inodep = sufile; + return 0; + failed: + iget_failed(sufile); + return err; +} |