/* * 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_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_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_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_host *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; } /** * gfs2_read_super - Read the gfs2 super block from disk * @sb: The VFS super block * @sector: The location of the super block * * This uses the bio functions to read the super block from disk * because we want to be 100% sure that we never read cached data. * A super block is read twice only during each GFS2 mount and is * never written to by the filesystem. The first time its read no * locks are held, and the only details which are looked at are those * relating to the locking protocol. Once locking is up and working, * the sb is read again under the lock to establish the location of * the master directory (contains pointers to journals etc) and the * root directory. * * Returns: A page containing the sb or NULL */ 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 * (sb->s_blocksize >> 9); 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, 0, 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_host head; int error; error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh); if (error) return error; gfs2_meta_cache_flush(ip); j_gl->gl_ops->go_inval(j_gl, DIO_METADATA); 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_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_host *m_sc = &sdp->sd_statfs_master; struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode); struct gfs2_statfs_change_host *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_host *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_host *m_sc = &sdp->sd_statfs_master; struct gfs2_statfs_change_host *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_host *sc) { struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master; struct gfs2_statfs_change_host *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_host *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_host *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_host)); 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_host 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); }