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-rw-r--r--fs/gfs2/super.c976
1 files changed, 976 insertions, 0 deletions
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
new file mode 100644
index 000000000000..6a78b1b32e25
--- /dev/null
+++ b/fs/gfs2/super.c
@@ -0,0 +1,976 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License version 2.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/crc32.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/bio.h>
+#include <linux/lm_interface.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "dir.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.h"
+#include "log.h"
+#include "meta_io.h"
+#include "quota.h"
+#include "recovery.h"
+#include "rgrp.h"
+#include "super.h"
+#include "trans.h"
+#include "util.h"
+
+static const u32 gfs2_old_fs_formats[] = {
+ 0
+};
+
+static const u32 gfs2_old_multihost_formats[] = {
+ 0
+};
+
+/**
+ * gfs2_tune_init - Fill a gfs2_tune structure with default values
+ * @gt: tune
+ *
+ */
+
+void gfs2_tune_init(struct gfs2_tune *gt)
+{
+ spin_lock_init(&gt->gt_spin);
+
+ gt->gt_ilimit = 100;
+ gt->gt_ilimit_tries = 3;
+ gt->gt_ilimit_min = 1;
+ gt->gt_demote_secs = 300;
+ gt->gt_incore_log_blocks = 1024;
+ gt->gt_log_flush_secs = 60;
+ gt->gt_jindex_refresh_secs = 60;
+ gt->gt_scand_secs = 15;
+ gt->gt_recoverd_secs = 60;
+ gt->gt_logd_secs = 1;
+ gt->gt_quotad_secs = 5;
+ gt->gt_quota_simul_sync = 64;
+ gt->gt_quota_warn_period = 10;
+ gt->gt_quota_scale_num = 1;
+ gt->gt_quota_scale_den = 1;
+ gt->gt_quota_cache_secs = 300;
+ gt->gt_quota_quantum = 60;
+ gt->gt_atime_quantum = 3600;
+ gt->gt_new_files_jdata = 0;
+ gt->gt_new_files_directio = 0;
+ gt->gt_max_atomic_write = 4 << 20;
+ gt->gt_max_readahead = 1 << 18;
+ gt->gt_lockdump_size = 131072;
+ gt->gt_stall_secs = 600;
+ gt->gt_complain_secs = 10;
+ gt->gt_reclaim_limit = 5000;
+ gt->gt_entries_per_readdir = 32;
+ gt->gt_prefetch_secs = 10;
+ gt->gt_greedy_default = HZ / 10;
+ gt->gt_greedy_quantum = HZ / 40;
+ gt->gt_greedy_max = HZ / 4;
+ gt->gt_statfs_quantum = 30;
+ gt->gt_statfs_slow = 0;
+}
+
+/**
+ * gfs2_check_sb - Check superblock
+ * @sdp: the filesystem
+ * @sb: The superblock
+ * @silent: Don't print a message if the check fails
+ *
+ * Checks the version code of the FS is one that we understand how to
+ * read and that the sizes of the various on-disk structures have not
+ * changed.
+ */
+
+int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb *sb, int silent)
+{
+ unsigned int x;
+
+ if (sb->sb_header.mh_magic != GFS2_MAGIC ||
+ sb->sb_header.mh_type != GFS2_METATYPE_SB) {
+ if (!silent)
+ printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
+ return -EINVAL;
+ }
+
+ /* If format numbers match exactly, we're done. */
+
+ if (sb->sb_fs_format == GFS2_FORMAT_FS &&
+ sb->sb_multihost_format == GFS2_FORMAT_MULTI)
+ return 0;
+
+ if (sb->sb_fs_format != GFS2_FORMAT_FS) {
+ for (x = 0; gfs2_old_fs_formats[x]; x++)
+ if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
+ break;
+
+ if (!gfs2_old_fs_formats[x]) {
+ printk(KERN_WARNING
+ "GFS2: code version (%u, %u) is incompatible "
+ "with ondisk format (%u, %u)\n",
+ GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
+ sb->sb_fs_format, sb->sb_multihost_format);
+ printk(KERN_WARNING
+ "GFS2: I don't know how to upgrade this FS\n");
+ return -EINVAL;
+ }
+ }
+
+ if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
+ for (x = 0; gfs2_old_multihost_formats[x]; x++)
+ if (gfs2_old_multihost_formats[x] ==
+ sb->sb_multihost_format)
+ break;
+
+ if (!gfs2_old_multihost_formats[x]) {
+ printk(KERN_WARNING
+ "GFS2: code version (%u, %u) is incompatible "
+ "with ondisk format (%u, %u)\n",
+ GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
+ sb->sb_fs_format, sb->sb_multihost_format);
+ printk(KERN_WARNING
+ "GFS2: I don't know how to upgrade this FS\n");
+ return -EINVAL;
+ }
+ }
+
+ if (!sdp->sd_args.ar_upgrade) {
+ printk(KERN_WARNING
+ "GFS2: code version (%u, %u) is incompatible "
+ "with ondisk format (%u, %u)\n",
+ GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
+ sb->sb_fs_format, sb->sb_multihost_format);
+ printk(KERN_INFO
+ "GFS2: Use the \"upgrade\" mount option to upgrade "
+ "the FS\n");
+ printk(KERN_INFO "GFS2: See the manual for more details\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+
+static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
+{
+ struct page *page = bio->bi_private;
+ if (bio->bi_size)
+ return 1;
+
+ if (!error)
+ SetPageUptodate(page);
+ else
+ printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
+ unlock_page(page);
+ return 0;
+}
+
+struct page *gfs2_read_super(struct super_block *sb, sector_t sector)
+{
+ struct page *page;
+ struct bio *bio;
+
+ page = alloc_page(GFP_KERNEL);
+ if (unlikely(!page))
+ return NULL;
+
+ ClearPageUptodate(page);
+ ClearPageDirty(page);
+ lock_page(page);
+
+ bio = bio_alloc(GFP_KERNEL, 1);
+ if (unlikely(!bio)) {
+ __free_page(page);
+ return NULL;
+ }
+
+ bio->bi_sector = sector;
+ bio->bi_bdev = sb->s_bdev;
+ bio_add_page(bio, page, PAGE_SIZE, 0);
+
+ bio->bi_end_io = end_bio_io_page;
+ bio->bi_private = page;
+ submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
+ wait_on_page_locked(page);
+ bio_put(bio);
+ if (!PageUptodate(page)) {
+ __free_page(page);
+ return NULL;
+ }
+ return page;
+}
+
+/**
+ * gfs2_read_sb - Read super block
+ * @sdp: The GFS2 superblock
+ * @gl: the glock for the superblock (assumed to be held)
+ * @silent: Don't print message if mount fails
+ *
+ */
+
+int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
+{
+ u32 hash_blocks, ind_blocks, leaf_blocks;
+ u32 tmp_blocks;
+ unsigned int x;
+ int error;
+ struct page *page;
+ char *sb;
+
+ page = gfs2_read_super(sdp->sd_vfs, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
+ if (!page) {
+ if (!silent)
+ fs_err(sdp, "can't read superblock\n");
+ return -EIO;
+ }
+ sb = kmap(page);
+ gfs2_sb_in(&sdp->sd_sb, sb);
+ kunmap(page);
+ __free_page(page);
+
+ error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
+ if (error)
+ return error;
+
+ sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
+ GFS2_BASIC_BLOCK_SHIFT;
+ sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
+ sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_dinode)) / sizeof(u64);
+ sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_meta_header)) / sizeof(u64);
+ sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
+ sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
+ sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
+ sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
+ sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_meta_header)) /
+ sizeof(struct gfs2_quota_change);
+
+ /* Compute maximum reservation required to add a entry to a directory */
+
+ hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
+ sdp->sd_jbsize);
+
+ ind_blocks = 0;
+ for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
+ tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
+ ind_blocks += tmp_blocks;
+ }
+
+ leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
+
+ sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
+
+ sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_dinode);
+ sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
+ for (x = 2;; x++) {
+ u64 space, d;
+ u32 m;
+
+ space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
+ d = space;
+ m = do_div(d, sdp->sd_inptrs);
+
+ if (d != sdp->sd_heightsize[x - 1] || m)
+ break;
+ sdp->sd_heightsize[x] = space;
+ }
+ sdp->sd_max_height = x;
+ gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
+
+ sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
+ sizeof(struct gfs2_dinode);
+ sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
+ for (x = 2;; x++) {
+ u64 space, d;
+ u32 m;
+
+ space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
+ d = space;
+ m = do_div(d, sdp->sd_inptrs);
+
+ if (d != sdp->sd_jheightsize[x - 1] || m)
+ break;
+ sdp->sd_jheightsize[x] = space;
+ }
+ sdp->sd_max_jheight = x;
+ gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
+
+ return 0;
+}
+
+/**
+ * gfs2_jindex_hold - Grab a lock on the jindex
+ * @sdp: The GFS2 superblock
+ * @ji_gh: the holder for the jindex glock
+ *
+ * This is very similar to the gfs2_rindex_hold() function, except that
+ * in general we hold the jindex lock for longer periods of time and
+ * we grab it far less frequently (in general) then the rgrp lock.
+ *
+ * Returns: errno
+ */
+
+int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
+{
+ struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
+ struct qstr name;
+ char buf[20];
+ struct gfs2_jdesc *jd;
+ int error;
+
+ name.name = buf;
+
+ mutex_lock(&sdp->sd_jindex_mutex);
+
+ for (;;) {
+ error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
+ GL_LOCAL_EXCL, ji_gh);
+ if (error)
+ break;
+
+ name.len = sprintf(buf, "journal%u", sdp->sd_journals);
+ name.hash = gfs2_disk_hash(name.name, name.len);
+
+ error = gfs2_dir_search(sdp->sd_jindex, &name, NULL, NULL);
+ if (error == -ENOENT) {
+ error = 0;
+ break;
+ }
+
+ gfs2_glock_dq_uninit(ji_gh);
+
+ if (error)
+ break;
+
+ error = -ENOMEM;
+ jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
+ if (!jd)
+ break;
+
+ jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
+ if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
+ if (!jd->jd_inode)
+ error = -ENOENT;
+ else
+ error = PTR_ERR(jd->jd_inode);
+ kfree(jd);
+ break;
+ }
+
+ spin_lock(&sdp->sd_jindex_spin);
+ jd->jd_jid = sdp->sd_journals++;
+ list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
+ spin_unlock(&sdp->sd_jindex_spin);
+ }
+
+ mutex_unlock(&sdp->sd_jindex_mutex);
+
+ return error;
+}
+
+/**
+ * gfs2_jindex_free - Clear all the journal index information
+ * @sdp: The GFS2 superblock
+ *
+ */
+
+void gfs2_jindex_free(struct gfs2_sbd *sdp)
+{
+ struct list_head list;
+ struct gfs2_jdesc *jd;
+
+ spin_lock(&sdp->sd_jindex_spin);
+ list_add(&list, &sdp->sd_jindex_list);
+ list_del_init(&sdp->sd_jindex_list);
+ sdp->sd_journals = 0;
+ spin_unlock(&sdp->sd_jindex_spin);
+
+ while (!list_empty(&list)) {
+ jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
+ list_del(&jd->jd_list);
+ iput(jd->jd_inode);
+ kfree(jd);
+ }
+}
+
+static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
+{
+ struct gfs2_jdesc *jd;
+ int found = 0;
+
+ list_for_each_entry(jd, head, jd_list) {
+ if (jd->jd_jid == jid) {
+ found = 1;
+ break;
+ }
+ }
+
+ if (!found)
+ jd = NULL;
+
+ return jd;
+}
+
+struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
+{
+ struct gfs2_jdesc *jd;
+
+ spin_lock(&sdp->sd_jindex_spin);
+ jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
+ spin_unlock(&sdp->sd_jindex_spin);
+
+ return jd;
+}
+
+void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
+{
+ struct gfs2_jdesc *jd;
+
+ spin_lock(&sdp->sd_jindex_spin);
+ jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
+ if (jd)
+ jd->jd_dirty = 1;
+ spin_unlock(&sdp->sd_jindex_spin);
+}
+
+struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
+{
+ struct gfs2_jdesc *jd;
+ int found = 0;
+
+ spin_lock(&sdp->sd_jindex_spin);
+
+ list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+ if (jd->jd_dirty) {
+ jd->jd_dirty = 0;
+ found = 1;
+ break;
+ }
+ }
+ spin_unlock(&sdp->sd_jindex_spin);
+
+ if (!found)
+ jd = NULL;
+
+ return jd;
+}
+
+int gfs2_jdesc_check(struct gfs2_jdesc *jd)
+{
+ struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
+ struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+ int ar;
+ int error;
+
+ if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
+ (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
+ gfs2_consist_inode(ip);
+ return -EIO;
+ }
+ jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
+
+ error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
+ if (!error && ar) {
+ gfs2_consist_inode(ip);
+ error = -EIO;
+ }
+
+ return error;
+}
+
+/**
+ * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
+{
+ struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
+ struct gfs2_glock *j_gl = ip->i_gl;
+ struct gfs2_holder t_gh;
+ struct gfs2_log_header head;
+ int error;
+
+ error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
+ GL_LOCAL_EXCL, &t_gh);
+ if (error)
+ return error;
+
+ gfs2_meta_cache_flush(ip);
+ j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
+
+ error = gfs2_find_jhead(sdp->sd_jdesc, &head);
+ if (error)
+ goto fail;
+
+ if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+ gfs2_consist(sdp);
+ error = -EIO;
+ goto fail;
+ }
+
+ /* Initialize some head of the log stuff */
+ sdp->sd_log_sequence = head.lh_sequence + 1;
+ gfs2_log_pointers_init(sdp, head.lh_blkno);
+
+ error = gfs2_quota_init(sdp);
+ if (error)
+ goto fail;
+
+ set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+
+ gfs2_glock_dq_uninit(&t_gh);
+
+ return 0;
+
+fail:
+ t_gh.gh_flags |= GL_NOCACHE;
+ gfs2_glock_dq_uninit(&t_gh);
+
+ return error;
+}
+
+/**
+ * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
+{
+ struct gfs2_holder t_gh;
+ int error;
+
+ gfs2_quota_sync(sdp);
+ gfs2_statfs_sync(sdp);
+
+ error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
+ GL_LOCAL_EXCL | GL_NOCACHE,
+ &t_gh);
+ if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+ return error;
+
+ gfs2_meta_syncfs(sdp);
+ gfs2_log_shutdown(sdp);
+
+ clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+
+ if (t_gh.gh_gl)
+ gfs2_glock_dq_uninit(&t_gh);
+
+ gfs2_quota_cleanup(sdp);
+
+ return error;
+}
+
+int gfs2_statfs_init(struct gfs2_sbd *sdp)
+{
+ struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+ struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
+ struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+ struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
+ struct buffer_head *m_bh, *l_bh;
+ struct gfs2_holder gh;
+ int error;
+
+ error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+ &gh);
+ if (error)
+ return error;
+
+ error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+ if (error)
+ goto out;
+
+ if (sdp->sd_args.ar_spectator) {
+ spin_lock(&sdp->sd_statfs_spin);
+ gfs2_statfs_change_in(m_sc, m_bh->b_data +
+ sizeof(struct gfs2_dinode));
+ spin_unlock(&sdp->sd_statfs_spin);
+ } else {
+ error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+ if (error)
+ goto out_m_bh;
+
+ spin_lock(&sdp->sd_statfs_spin);
+ gfs2_statfs_change_in(m_sc, m_bh->b_data +
+ sizeof(struct gfs2_dinode));
+ gfs2_statfs_change_in(l_sc, l_bh->b_data +
+ sizeof(struct gfs2_dinode));
+ spin_unlock(&sdp->sd_statfs_spin);
+
+ brelse(l_bh);
+ }
+
+out_m_bh:
+ brelse(m_bh);
+out:
+ gfs2_glock_dq_uninit(&gh);
+ return 0;
+}
+
+void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
+ s64 dinodes)
+{
+ struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+ struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
+ struct buffer_head *l_bh;
+ int error;
+
+ error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+ if (error)
+ return;
+
+ mutex_lock(&sdp->sd_statfs_mutex);
+ gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
+ mutex_unlock(&sdp->sd_statfs_mutex);
+
+ spin_lock(&sdp->sd_statfs_spin);
+ l_sc->sc_total += total;
+ l_sc->sc_free += free;
+ l_sc->sc_dinodes += dinodes;
+ gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
+ spin_unlock(&sdp->sd_statfs_spin);
+
+ brelse(l_bh);
+}
+
+int gfs2_statfs_sync(struct gfs2_sbd *sdp)
+{
+ struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+ struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+ struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
+ struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
+ struct gfs2_holder gh;
+ struct buffer_head *m_bh, *l_bh;
+ int error;
+
+ error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+ &gh);
+ if (error)
+ return error;
+
+ error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+ if (error)
+ goto out;
+
+ spin_lock(&sdp->sd_statfs_spin);
+ gfs2_statfs_change_in(m_sc, m_bh->b_data +
+ sizeof(struct gfs2_dinode));
+ if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
+ spin_unlock(&sdp->sd_statfs_spin);
+ goto out_bh;
+ }
+ spin_unlock(&sdp->sd_statfs_spin);
+
+ error = gfs2_meta_inode_buffer(l_ip, &l_bh);
+ if (error)
+ goto out_bh;
+
+ error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
+ if (error)
+ goto out_bh2;
+
+ mutex_lock(&sdp->sd_statfs_mutex);
+ gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
+ mutex_unlock(&sdp->sd_statfs_mutex);
+
+ spin_lock(&sdp->sd_statfs_spin);
+ m_sc->sc_total += l_sc->sc_total;
+ m_sc->sc_free += l_sc->sc_free;
+ m_sc->sc_dinodes += l_sc->sc_dinodes;
+ memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
+ memset(l_bh->b_data + sizeof(struct gfs2_dinode),
+ 0, sizeof(struct gfs2_statfs_change));
+ spin_unlock(&sdp->sd_statfs_spin);
+
+ gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
+ gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
+
+ gfs2_trans_end(sdp);
+
+out_bh2:
+ brelse(l_bh);
+out_bh:
+ brelse(m_bh);
+out:
+ gfs2_glock_dq_uninit(&gh);
+ return error;
+}
+
+/**
+ * gfs2_statfs_i - Do a statfs
+ * @sdp: the filesystem
+ * @sg: the sg structure
+ *
+ * Returns: errno
+ */
+
+int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
+{
+ struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
+ struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
+
+ spin_lock(&sdp->sd_statfs_spin);
+
+ *sc = *m_sc;
+ sc->sc_total += l_sc->sc_total;
+ sc->sc_free += l_sc->sc_free;
+ sc->sc_dinodes += l_sc->sc_dinodes;
+
+ spin_unlock(&sdp->sd_statfs_spin);
+
+ if (sc->sc_free < 0)
+ sc->sc_free = 0;
+ if (sc->sc_free > sc->sc_total)
+ sc->sc_free = sc->sc_total;
+ if (sc->sc_dinodes < 0)
+ sc->sc_dinodes = 0;
+
+ return 0;
+}
+
+/**
+ * statfs_fill - fill in the sg for a given RG
+ * @rgd: the RG
+ * @sc: the sc structure
+ *
+ * Returns: 0 on success, -ESTALE if the LVB is invalid
+ */
+
+static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
+ struct gfs2_statfs_change *sc)
+{
+ gfs2_rgrp_verify(rgd);
+ sc->sc_total += rgd->rd_ri.ri_data;
+ sc->sc_free += rgd->rd_rg.rg_free;
+ sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
+ return 0;
+}
+
+/**
+ * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
+ * @sdp: the filesystem
+ * @sc: the sc info that will be returned
+ *
+ * Any error (other than a signal) will cause this routine to fall back
+ * to the synchronous version.
+ *
+ * FIXME: This really shouldn't busy wait like this.
+ *
+ * Returns: errno
+ */
+
+int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
+{
+ struct gfs2_holder ri_gh;
+ struct gfs2_rgrpd *rgd_next;
+ struct gfs2_holder *gha, *gh;
+ unsigned int slots = 64;
+ unsigned int x;
+ int done;
+ int error = 0, err;
+
+ memset(sc, 0, sizeof(struct gfs2_statfs_change));
+ gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
+ if (!gha)
+ return -ENOMEM;
+
+ error = gfs2_rindex_hold(sdp, &ri_gh);
+ if (error)
+ goto out;
+
+ rgd_next = gfs2_rgrpd_get_first(sdp);
+
+ for (;;) {
+ done = 1;
+
+ for (x = 0; x < slots; x++) {
+ gh = gha + x;
+
+ if (gh->gh_gl && gfs2_glock_poll(gh)) {
+ err = gfs2_glock_wait(gh);
+ if (err) {
+ gfs2_holder_uninit(gh);
+ error = err;
+ } else {
+ if (!error)
+ error = statfs_slow_fill(
+ gh->gh_gl->gl_object, sc);
+ gfs2_glock_dq_uninit(gh);
+ }
+ }
+
+ if (gh->gh_gl)
+ done = 0;
+ else if (rgd_next && !error) {
+ error = gfs2_glock_nq_init(rgd_next->rd_gl,
+ LM_ST_SHARED,
+ GL_ASYNC,
+ gh);
+ rgd_next = gfs2_rgrpd_get_next(rgd_next);
+ done = 0;
+ }
+
+ if (signal_pending(current))
+ error = -ERESTARTSYS;
+ }
+
+ if (done)
+ break;
+
+ yield();
+ }
+
+ gfs2_glock_dq_uninit(&ri_gh);
+
+out:
+ kfree(gha);
+ return error;
+}
+
+struct lfcc {
+ struct list_head list;
+ struct gfs2_holder gh;
+};
+
+/**
+ * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
+ * journals are clean
+ * @sdp: the file system
+ * @state: the state to put the transaction lock into
+ * @t_gh: the hold on the transaction lock
+ *
+ * Returns: errno
+ */
+
+static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
+ struct gfs2_holder *t_gh)
+{
+ struct gfs2_inode *ip;
+ struct gfs2_holder ji_gh;
+ struct gfs2_jdesc *jd;
+ struct lfcc *lfcc;
+ LIST_HEAD(list);
+ struct gfs2_log_header lh;
+ int error;
+
+ error = gfs2_jindex_hold(sdp, &ji_gh);
+ if (error)
+ return error;
+
+ list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+ lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
+ if (!lfcc) {
+ error = -ENOMEM;
+ goto out;
+ }
+ ip = GFS2_I(jd->jd_inode);
+ error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
+ if (error) {
+ kfree(lfcc);
+ goto out;
+ }
+ list_add(&lfcc->list, &list);
+ }
+
+ error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
+ LM_FLAG_PRIORITY | GL_NOCACHE,
+ t_gh);
+
+ list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+ error = gfs2_jdesc_check(jd);
+ if (error)
+ break;
+ error = gfs2_find_jhead(jd, &lh);
+ if (error)
+ break;
+ if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+ error = -EBUSY;
+ break;
+ }
+ }
+
+ if (error)
+ gfs2_glock_dq_uninit(t_gh);
+
+out:
+ while (!list_empty(&list)) {
+ lfcc = list_entry(list.next, struct lfcc, list);
+ list_del(&lfcc->list);
+ gfs2_glock_dq_uninit(&lfcc->gh);
+ kfree(lfcc);
+ }
+ gfs2_glock_dq_uninit(&ji_gh);
+ return error;
+}
+
+/**
+ * gfs2_freeze_fs - freezes the file system
+ * @sdp: the file system
+ *
+ * This function flushes data and meta data for all machines by
+ * aquiring the transaction log exclusively. All journals are
+ * ensured to be in a clean state as well.
+ *
+ * Returns: errno
+ */
+
+int gfs2_freeze_fs(struct gfs2_sbd *sdp)
+{
+ int error = 0;
+
+ mutex_lock(&sdp->sd_freeze_lock);
+
+ if (!sdp->sd_freeze_count++) {
+ error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
+ if (error)
+ sdp->sd_freeze_count--;
+ }
+
+ mutex_unlock(&sdp->sd_freeze_lock);
+
+ return error;
+}
+
+/**
+ * gfs2_unfreeze_fs - unfreezes the file system
+ * @sdp: the file system
+ *
+ * This function allows the file system to proceed by unlocking
+ * the exclusively held transaction lock. Other GFS2 nodes are
+ * now free to acquire the lock shared and go on with their lives.
+ *
+ */
+
+void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
+{
+ mutex_lock(&sdp->sd_freeze_lock);
+
+ if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
+ gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
+
+ mutex_unlock(&sdp->sd_freeze_lock);
+}
+