--- /dev/null
+/*
+ * 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 - 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))) {
+ 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_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, ncleansegs, 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);
+ ncleansegs = le64_to_cpu(header->sh_ncleansegs);
+ 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 */
+ }
+ }
+ 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;
+ 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))) {
+ printk(KERN_WARNING "%s: segment %llu must be clean\n",
+ __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(1UL << 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(1UL << 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)) {
+ printk(KERN_WARNING "%s: segment %llu is already clean\n",
+ __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);
+}
+
+/**
+ * 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) {
+ 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);
+ 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);
+
+ 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 = 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) &
+ ~(1UL << 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;
+ }
+
+ 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 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) &
+ ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
+ if (nilfs_segment_is_active(nilfs, segnum + j))
+ si->sui_flags |=
+ (1UL << 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 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 &=
+ ~(1UL << 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, 0);
+ 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, 0);
+ 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) {
+ printk(KERN_ERR
+ "NILFS: too large segment usage size: %zu bytes.\n",
+ susize);
+ return -EINVAL;
+ } else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
+ printk(KERN_ERR
+ "NILFS: too small segment usage size: %zu bytes.\n",
+ 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;
+}
Code Review / kvmfornfv.git / blobdiff