/* * sufile.c - NILFS segment usage file. * * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * Written by Koji Sato <koji@osrg.net>. * Revised by Ryusuke Konishi <ryusuke@osrg.net>. */ #include <linux/kernel.h> #include <linux/fs.h> #include <linux/string.h> #include <linux/buffer_head.h> #include <linux/errno.h> #include <linux/nilfs2_fs.h> #include "mdt.h" #include "sufile.h" struct nilfs_sufile_info { struct nilfs_mdt_info mi; unsigned long ncleansegs; }; 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 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, KM_USER0); header = kaddr + bh_offset(header_bh); le64_add_cpu(&header->sh_ncleansegs, ncleanadd); le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd); kunmap_atomic(kaddr, KM_USER0); nilfs_mdt_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))) { printk(KERN_WARNING "%s: invalid segment number: %llu\n", __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))) { printk(KERN_WARNING "%s: invalid segment number: %llu\n", __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_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; 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; 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, KM_USER0); header = kaddr + bh_offset(header_bh); ncleansegs = le64_to_cpu(header->sh_ncleansegs); last_alloc = le64_to_cpu(header->sh_last_alloc); kunmap_atomic(kaddr, KM_USER0); nsegments = nilfs_sufile_get_nsegments(sufile); segnum = last_alloc + 1; maxsegnum = nsegments - 1; for (i = 0; i < nsegments; i += nsus) { if (segnum >= nsegments) { /* wrap around */ segnum = 0; maxsegnum = last_alloc; } 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, KM_USER0); 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, KM_USER0); kaddr = kmap_atomic(header_bh->b_page, KM_USER0); 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, KM_USER0); NILFS_SUI(sufile)->ncleansegs--; nilfs_mdt_mark_buffer_dirty(header_bh); nilfs_mdt_mark_buffer_dirty(su_bh); nilfs_mdt_mark_dirty(sufile); brelse(su_bh); *segnump = segnum; goto out_header; } kunmap_atomic(kaddr, KM_USER0); 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, KM_USER0); su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); if (unlikely(!nilfs_segment_usage_clean(su))) { printk(KERN_WARNING "%s: segment %llu must be clean\n", __func__, (unsigned long long)segnum); kunmap_atomic(kaddr, KM_USER0); return; } nilfs_segment_usage_set_dirty(su); kunmap_atomic(kaddr, KM_USER0); nilfs_sufile_mod_counter(header_bh, -1, 1); NILFS_SUI(sufile)->ncleansegs--; nilfs_mdt_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, KM_USER0); su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) && su->su_nblocks == cpu_to_le32(0)) { kunmap_atomic(kaddr, KM_USER0); 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(1UL << NILFS_SEGMENT_USAGE_DIRTY); kunmap_atomic(kaddr, KM_USER0); nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1); NILFS_SUI(sufile)->ncleansegs -= clean; nilfs_mdt_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, KM_USER0); su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); if (nilfs_segment_usage_clean(su)) { printk(KERN_WARNING "%s: segment %llu is already clean\n", __func__, (unsigned long long)segnum); kunmap_atomic(kaddr, KM_USER0); 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, KM_USER0); nilfs_mdt_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); } /** * 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; int ret; ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh); if (!ret) { nilfs_mdt_mark_buffer_dirty(bh); nilfs_mdt_mark_dirty(sufile); brelse(bh); } 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, time_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, KM_USER0); su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr); WARN_ON(nilfs_segment_usage_error(su)); if (modtime) su->su_lastmod = cpu_to_le64(modtime); su->su_nblocks = cpu_to_le32(nblocks); kunmap_atomic(kaddr, KM_USER0); nilfs_mdt_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 * @stat: 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 @stat. 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 = NILFS_MDT(sufile)->mi_nilfs; 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, KM_USER0); 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, KM_USER0); 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, KM_USER0); su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); if (nilfs_segment_usage_error(su)) { kunmap_atomic(kaddr, KM_USER0); return; } suclean = nilfs_segment_usage_clean(su); nilfs_segment_usage_set_error(su); kunmap_atomic(kaddr, KM_USER0); if (suclean) { nilfs_sufile_mod_counter(header_bh, -1, 0); NILFS_SUI(sufile)->ncleansegs--; } nilfs_mdt_mark_buffer_dirty(su_bh); nilfs_mdt_mark_dirty(sufile); } /** * 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 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 = NILFS_MDT(sufile)->mi_nilfs; 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, KM_USER0); 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) & ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE); if (nilfs_segment_is_active(nilfs, segnum + j)) si->sui_flags |= (1UL << NILFS_SEGMENT_USAGE_ACTIVE); } kunmap_atomic(kaddr, KM_USER0); brelse(su_bh); } ret = nsegs; out: up_read(&NILFS_MDT(sufile)->mi_sem); return ret; } /** * nilfs_sufile_read - read sufile inode * @sufile: sufile inode * @raw_inode: on-disk sufile inode */ int nilfs_sufile_read(struct inode *sufile, struct nilfs_inode *raw_inode) { struct nilfs_sufile_info *sui = NILFS_SUI(sufile); struct buffer_head *header_bh; struct nilfs_sufile_header *header; void *kaddr; int ret; ret = nilfs_read_inode_common(sufile, raw_inode); if (ret < 0) return ret; ret = nilfs_sufile_get_header_block(sufile, &header_bh); if (!ret) { kaddr = kmap_atomic(header_bh->b_page, KM_USER0); header = kaddr + bh_offset(header_bh); sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs); kunmap_atomic(kaddr, KM_USER0); brelse(header_bh); } return ret; } /** * nilfs_sufile_new - create sufile * @nilfs: nilfs object * @susize: size of a segment usage entry */ struct inode *nilfs_sufile_new(struct the_nilfs *nilfs, size_t susize) { struct inode *sufile; sufile = nilfs_mdt_new(nilfs, NULL, NILFS_SUFILE_INO, sizeof(struct nilfs_sufile_info)); if (sufile) nilfs_mdt_set_entry_size(sufile, susize, sizeof(struct nilfs_sufile_header)); return sufile; }