diff options
| -rw-r--r-- | fs/ext2/inode.c | 4 | ||||
| -rw-r--r-- | fs/notify/inode_mark.c | 45 | ||||
| -rw-r--r-- | fs/ocfs2/quota_global.c | 10 | ||||
| -rw-r--r-- | fs/ocfs2/quota_local.c | 11 | ||||
| -rw-r--r-- | fs/ocfs2/super.c | 1 | ||||
| -rw-r--r-- | fs/quota/dquot.c | 136 | ||||
| -rw-r--r-- | fs/quota/quota.c | 22 | ||||
| -rw-r--r-- | fs/super.c | 81 | ||||
| -rw-r--r-- | include/linux/fs.h | 2 | ||||
| -rw-r--r-- | include/linux/quota.h | 1 |
10 files changed, 152 insertions, 161 deletions
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index e173afe92661..0093ea2512a8 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1478,6 +1478,10 @@ struct inode *ext2_iget (struct super_block *sb, unsigned long ino) inode->i_size |= ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; else ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); + if (i_size_read(inode) < 0) { + ret = -EFSCORRUPTED; + goto bad_inode; + } ei->i_dtime = 0; inode->i_generation = le32_to_cpu(raw_inode->i_generation); ei->i_state = 0; diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c index 741077deef3b..a3645249f7ec 100644 --- a/fs/notify/inode_mark.c +++ b/fs/notify/inode_mark.c @@ -150,12 +150,10 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, */ void fsnotify_unmount_inodes(struct super_block *sb) { - struct inode *inode, *next_i, *need_iput = NULL; + struct inode *inode, *iput_inode = NULL; spin_lock(&sb->s_inode_list_lock); - list_for_each_entry_safe(inode, next_i, &sb->s_inodes, i_sb_list) { - struct inode *need_iput_tmp; - + list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { /* * We cannot __iget() an inode in state I_FREEING, * I_WILL_FREE, or I_NEW which is fine because by that point @@ -178,49 +176,24 @@ void fsnotify_unmount_inodes(struct super_block *sb) continue; } - need_iput_tmp = need_iput; - need_iput = NULL; - - /* In case fsnotify_inode_delete() drops a reference. */ - if (inode != need_iput_tmp) - __iget(inode); - else - need_iput_tmp = NULL; + __iget(inode); spin_unlock(&inode->i_lock); - - /* In case the dropping of a reference would nuke next_i. */ - while (&next_i->i_sb_list != &sb->s_inodes) { - spin_lock(&next_i->i_lock); - if (!(next_i->i_state & (I_FREEING | I_WILL_FREE)) && - atomic_read(&next_i->i_count)) { - __iget(next_i); - need_iput = next_i; - spin_unlock(&next_i->i_lock); - break; - } - spin_unlock(&next_i->i_lock); - next_i = list_next_entry(next_i, i_sb_list); - } - - /* - * We can safely drop s_inode_list_lock here because either - * we actually hold references on both inode and next_i or - * end of list. Also no new inodes will be added since the - * umount has begun. - */ spin_unlock(&sb->s_inode_list_lock); - if (need_iput_tmp) - iput(need_iput_tmp); + if (iput_inode) + iput(iput_inode); /* for each watch, send FS_UNMOUNT and then remove it */ fsnotify(inode, FS_UNMOUNT, inode, FSNOTIFY_EVENT_INODE, NULL, 0); fsnotify_inode_delete(inode); - iput(inode); + iput_inode = inode; spin_lock(&sb->s_inode_list_lock); } spin_unlock(&sb->s_inode_list_lock); + + if (iput_inode) + iput(iput_inode); } diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c index 87e577a49b0d..cec495a921e3 100644 --- a/fs/ocfs2/quota_global.c +++ b/fs/ocfs2/quota_global.c @@ -634,7 +634,15 @@ static void qsync_work_fn(struct work_struct *work) dqi_sync_work.work); struct super_block *sb = oinfo->dqi_gqinode->i_sb; - dquot_scan_active(sb, ocfs2_sync_dquot_helper, oinfo->dqi_type); + /* + * We have to be careful here not to deadlock on s_umount as umount + * disabling quotas may be in progress and it waits for this work to + * complete. If trylock fails, we'll do the sync next time... + */ + if (down_read_trylock(&sb->s_umount)) { + dquot_scan_active(sb, ocfs2_sync_dquot_helper, oinfo->dqi_type); + up_read(&sb->s_umount); + } schedule_delayed_work(&oinfo->dqi_sync_work, msecs_to_jiffies(oinfo->dqi_syncms)); } diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c index 8a54fd8a4fa5..32c5a40c1257 100644 --- a/fs/ocfs2/quota_local.c +++ b/fs/ocfs2/quota_local.c @@ -454,7 +454,7 @@ out: /* Sync changes in local quota file into global quota file and * reinitialize local quota file. * The function expects local quota file to be already locked and - * dqonoff_mutex locked. */ + * s_umount locked in shared mode. */ static int ocfs2_recover_local_quota_file(struct inode *lqinode, int type, struct ocfs2_quota_recovery *rec) @@ -597,7 +597,7 @@ int ocfs2_finish_quota_recovery(struct ocfs2_super *osb, printk(KERN_NOTICE "ocfs2: Finishing quota recovery on device (%s) for " "slot %u\n", osb->dev_str, slot_num); - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); + down_read(&sb->s_umount); for (type = 0; type < OCFS2_MAXQUOTAS; type++) { if (list_empty(&(rec->r_list[type]))) continue; @@ -674,7 +674,7 @@ out_put: break; } out: - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + up_read(&sb->s_umount); kfree(rec); return status; } @@ -840,7 +840,10 @@ static int ocfs2_local_free_info(struct super_block *sb, int type) } ocfs2_release_local_quota_bitmaps(&oinfo->dqi_chunk); - /* dqonoff_mutex protects us against racing with recovery thread... */ + /* + * s_umount held in exclusive mode protects us against racing with + * recovery thread... + */ if (oinfo->dqi_rec) { ocfs2_free_quota_recovery(oinfo->dqi_rec); mark_clean = 0; diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c index c894d945b084..a24e42f95341 100644 --- a/fs/ocfs2/super.c +++ b/fs/ocfs2/super.c @@ -985,7 +985,6 @@ static void ocfs2_disable_quotas(struct ocfs2_super *osb) for (type = 0; type < OCFS2_MAXQUOTAS; type++) { if (!sb_has_quota_loaded(sb, type)) continue; - /* Cancel periodic syncing before we grab dqonoff_mutex */ oinfo = sb_dqinfo(sb, type)->dqi_priv; cancel_delayed_work_sync(&oinfo->dqi_sync_work); inode = igrab(sb->s_dquot.files[type]); diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index 8738a0d62c09..406fed92362a 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -119,8 +119,7 @@ * spinlock to internal buffers before writing. * * Lock ordering (including related VFS locks) is the following: - * dqonoff_mutex > i_mutex > journal_lock > dquot->dq_lock > dqio_mutex - * dqonoff_mutex > i_mutex comes from dquot_quota_sync, dquot_enable, etc. + * s_umount > i_mutex > journal_lock > dquot->dq_lock > dqio_mutex */ static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock); @@ -572,7 +571,8 @@ int dquot_scan_active(struct super_block *sb, struct dquot *dquot, *old_dquot = NULL; int ret = 0; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); + WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)); + spin_lock(&dq_list_lock); list_for_each_entry(dquot, &inuse_list, dq_inuse) { if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) @@ -603,7 +603,6 @@ int dquot_scan_active(struct super_block *sb, spin_unlock(&dq_list_lock); out: dqput(old_dquot); - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return ret; } EXPORT_SYMBOL(dquot_scan_active); @@ -617,7 +616,8 @@ int dquot_writeback_dquots(struct super_block *sb, int type) int cnt; int err, ret = 0; - mutex_lock(&dqopt->dqonoff_mutex); + WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)); + for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; @@ -653,7 +653,6 @@ int dquot_writeback_dquots(struct super_block *sb, int type) && info_dirty(&dqopt->info[cnt])) sb->dq_op->write_info(sb, cnt); dqstats_inc(DQST_SYNCS); - mutex_unlock(&dqopt->dqonoff_mutex); return ret; } @@ -683,7 +682,6 @@ int dquot_quota_sync(struct super_block *sb, int type) * Now when everything is written we can discard the pagecache so * that userspace sees the changes. */ - mutex_lock(&dqopt->dqonoff_mutex); for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; @@ -693,7 +691,6 @@ int dquot_quota_sync(struct super_block *sb, int type) truncate_inode_pages(&dqopt->files[cnt]->i_data, 0); inode_unlock(dqopt->files[cnt]); } - mutex_unlock(&dqopt->dqonoff_mutex); return 0; } @@ -935,7 +932,7 @@ static int dqinit_needed(struct inode *inode, int type) return 0; } -/* This routine is guarded by dqonoff_mutex mutex */ +/* This routine is guarded by s_umount semaphore */ static void add_dquot_ref(struct super_block *sb, int type) { struct inode *inode, *old_inode = NULL; @@ -2050,21 +2047,13 @@ int dquot_get_next_id(struct super_block *sb, struct kqid *qid) struct quota_info *dqopt = sb_dqopt(sb); int err; - mutex_lock(&dqopt->dqonoff_mutex); - if (!sb_has_quota_active(sb, qid->type)) { - err = -ESRCH; - goto out; - } - if (!dqopt->ops[qid->type]->get_next_id) { - err = -ENOSYS; - goto out; - } + if (!sb_has_quota_active(sb, qid->type)) + return -ESRCH; + if (!dqopt->ops[qid->type]->get_next_id) + return -ENOSYS; mutex_lock(&dqopt->dqio_mutex); err = dqopt->ops[qid->type]->get_next_id(sb, qid); mutex_unlock(&dqopt->dqio_mutex); -out: - mutex_unlock(&dqopt->dqonoff_mutex); - return err; } EXPORT_SYMBOL(dquot_get_next_id); @@ -2107,6 +2096,10 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags) struct quota_info *dqopt = sb_dqopt(sb); struct inode *toputinode[MAXQUOTAS]; + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); + /* Cannot turn off usage accounting without turning off limits, or * suspend quotas and simultaneously turn quotas off. */ if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) @@ -2114,18 +2107,14 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags) DQUOT_USAGE_ENABLED))) return -EINVAL; - /* We need to serialize quota_off() for device */ - mutex_lock(&dqopt->dqonoff_mutex); - /* * Skip everything if there's nothing to do. We have to do this because * sometimes we are called when fill_super() failed and calling * sync_fs() in such cases does no good. */ - if (!sb_any_quota_loaded(sb)) { - mutex_unlock(&dqopt->dqonoff_mutex); + if (!sb_any_quota_loaded(sb)) return 0; - } + for (cnt = 0; cnt < MAXQUOTAS; cnt++) { toputinode[cnt] = NULL; if (type != -1 && cnt != type) @@ -2179,7 +2168,6 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags) dqopt->info[cnt].dqi_bgrace = 0; dqopt->ops[cnt] = NULL; } - mutex_unlock(&dqopt->dqonoff_mutex); /* Skip syncing and setting flags if quota files are hidden */ if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) @@ -2196,20 +2184,14 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags) * must also discard the blockdev buffers so that we see the * changes done by userspace on the next quotaon() */ for (cnt = 0; cnt < MAXQUOTAS; cnt++) - if (toputinode[cnt]) { - mutex_lock(&dqopt->dqonoff_mutex); - /* If quota was reenabled in the meantime, we have - * nothing to do */ - if (!sb_has_quota_loaded(sb, cnt)) { - inode_lock(toputinode[cnt]); - toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | + /* This can happen when suspending quotas on remount-ro... */ + if (toputinode[cnt] && !sb_has_quota_loaded(sb, cnt)) { + inode_lock(toputinode[cnt]); + toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | S_NOATIME | S_NOQUOTA); - truncate_inode_pages(&toputinode[cnt]->i_data, - 0); - inode_unlock(toputinode[cnt]); - mark_inode_dirty_sync(toputinode[cnt]); - } - mutex_unlock(&dqopt->dqonoff_mutex); + truncate_inode_pages(&toputinode[cnt]->i_data, 0); + inode_unlock(toputinode[cnt]); + mark_inode_dirty_sync(toputinode[cnt]); } if (sb->s_bdev) invalidate_bdev(sb->s_bdev); @@ -2281,6 +2263,10 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, error = -EINVAL; goto out_fmt; } + if (sb_has_quota_loaded(sb, type)) { + error = -EBUSY; + goto out_fmt; + } if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { /* As we bypass the pagecache we must now flush all the @@ -2292,11 +2278,6 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, sync_filesystem(sb); invalidate_bdev(sb->s_bdev); } - mutex_lock(&dqopt->dqonoff_mutex); - if (sb_has_quota_loaded(sb, type)) { - error = -EBUSY; - goto out_lock; - } if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { /* We don't want quota and atime on quota files (deadlocks @@ -2317,7 +2298,7 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, error = -EIO; dqopt->files[type] = igrab(inode); if (!dqopt->files[type]) - goto out_lock; + goto out_file_flags; error = -EINVAL; if (!fmt->qf_ops->check_quota_file(sb, type)) goto out_file_init; @@ -2340,14 +2321,13 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, spin_unlock(&dq_state_lock); add_dquot_ref(sb, type); - mutex_unlock(&dqopt->dqonoff_mutex); return 0; out_file_init: dqopt->files[type] = NULL; iput(inode); -out_lock: +out_file_flags: if (oldflags != -1) { inode_lock(inode); /* Set the flags back (in the case of accidental quotaon() @@ -2356,7 +2336,6 @@ out_lock: inode->i_flags |= oldflags; inode_unlock(inode); } - mutex_unlock(&dqopt->dqonoff_mutex); out_fmt: put_quota_format(fmt); @@ -2371,15 +2350,16 @@ int dquot_resume(struct super_block *sb, int type) int ret = 0, cnt; unsigned int flags; + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); + for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; - - mutex_lock(&dqopt->dqonoff_mutex); - if (!sb_has_quota_suspended(sb, cnt)) { - mutex_unlock(&dqopt->dqonoff_mutex); + if (!sb_has_quota_suspended(sb, cnt)) continue; - } + inode = dqopt->files[cnt]; dqopt->files[cnt] = NULL; spin_lock(&dq_state_lock); @@ -2388,7 +2368,6 @@ int dquot_resume(struct super_block *sb, int type) cnt); dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt); spin_unlock(&dq_state_lock); - mutex_unlock(&dqopt->dqonoff_mutex); flags = dquot_generic_flag(flags, cnt); ret = vfs_load_quota_inode(inode, cnt, @@ -2424,42 +2403,30 @@ EXPORT_SYMBOL(dquot_quota_on); int dquot_enable(struct inode *inode, int type, int format_id, unsigned int flags) { - int ret = 0; struct super_block *sb = inode->i_sb; - struct quota_info *dqopt = sb_dqopt(sb); /* Just unsuspend quotas? */ BUG_ON(flags & DQUOT_SUSPENDED); + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); if (!flags) return 0; /* Just updating flags needed? */ if (sb_has_quota_loaded(sb, type)) { - mutex_lock(&dqopt->dqonoff_mutex); - /* Now do a reliable test... */ - if (!sb_has_quota_loaded(sb, type)) { - mutex_unlock(&dqopt->dqonoff_mutex); - goto load_quota; - } if (flags & DQUOT_USAGE_ENABLED && - sb_has_quota_usage_enabled(sb, type)) { - ret = -EBUSY; - goto out_lock; - } + sb_has_quota_usage_enabled(sb, type)) + return -EBUSY; if (flags & DQUOT_LIMITS_ENABLED && - sb_has_quota_limits_enabled(sb, type)) { - ret = -EBUSY; - goto out_lock; - } + sb_has_quota_limits_enabled(sb, type)) + return -EBUSY; spin_lock(&dq_state_lock); sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); spin_unlock(&dq_state_lock); -out_lock: - mutex_unlock(&dqopt->dqonoff_mutex); - return ret; + return 0; } -load_quota: return vfs_load_quota_inode(inode, type, format_id, flags); } EXPORT_SYMBOL(dquot_enable); @@ -2751,7 +2718,6 @@ int dquot_get_state(struct super_block *sb, struct qc_state *state) struct quota_info *dqopt = sb_dqopt(sb); int type; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); memset(state, 0, sizeof(*state)); for (type = 0; type < MAXQUOTAS; type++) { if (!sb_has_quota_active(sb, type)) @@ -2773,7 +2739,6 @@ int dquot_get_state(struct super_block *sb, struct qc_state *state) tstate->nextents = 1; /* We don't know... */ spin_unlock(&dq_data_lock); } - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return 0; } EXPORT_SYMBOL(dquot_get_state); @@ -2787,18 +2752,13 @@ int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii) if ((ii->i_fieldmask & QC_WARNS_MASK) || (ii->i_fieldmask & QC_RT_SPC_TIMER)) return -EINVAL; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_active(sb, type)) { - err = -ESRCH; - goto out; - } + if (!sb_has_quota_active(sb, type)) + return -ESRCH; mi = sb_dqopt(sb)->info + type; if (ii->i_fieldmask & QC_FLAGS) { if ((ii->i_flags & QCI_ROOT_SQUASH && - mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD)) { - err = -EINVAL; - goto out; - } + mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD)) + return -EINVAL; } spin_lock(&dq_data_lock); if (ii->i_fieldmask & QC_SPC_TIMER) @@ -2815,8 +2775,6 @@ int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii) mark_info_dirty(sb, type); /* Force write to disk */ sb->dq_op->write_info(sb, type); -out: - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return err; } EXPORT_SYMBOL(dquot_set_dqinfo); diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 5acd0c4769af..07e08c7d05ca 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -104,13 +104,9 @@ static int quota_getfmt(struct super_block *sb, int type, void __user *addr) { __u32 fmt; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_active(sb, type)) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + if (!sb_has_quota_active(sb, type)) return -ESRCH; - } fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id; - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); if (copy_to_user(addr, &fmt, sizeof(fmt))) return -EFAULT; return 0; @@ -789,9 +785,14 @@ static int quotactl_cmd_write(int cmd) } return 1; } - #endif /* CONFIG_BLOCK */ +/* Return true if quotactl command is manipulating quota on/off state */ +static bool quotactl_cmd_onoff(int cmd) +{ + return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF); +} + /* * look up a superblock on which quota ops will be performed * - use the name of a block device to find the superblock thereon @@ -809,7 +810,9 @@ static struct super_block *quotactl_block(const char __user *special, int cmd) putname(tmp); if (IS_ERR(bdev)) return ERR_CAST(bdev); - if (quotactl_cmd_write(cmd)) + if (quotactl_cmd_onoff(cmd)) + sb = get_super_exclusive_thawed(bdev); + else if (quotactl_cmd_write(cmd)) sb = get_super_thawed(bdev); else sb = get_super(bdev); @@ -872,7 +875,10 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, ret = do_quotactl(sb, type, cmds, id, addr, pathp); - drop_super(sb); + if (!quotactl_cmd_onoff(cmds)) + drop_super(sb); + else + drop_super_exclusive(sb); out: if (pathp && !IS_ERR(pathp)) path_put(pathp); diff --git a/fs/super.c b/fs/super.c index c183835566c1..1709ed029a2c 100644 --- a/fs/super.c +++ b/fs/super.c @@ -244,7 +244,6 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags, mutex_init(&s->s_vfs_rename_mutex); lockdep_set_class(&s->s_vfs_rename_mutex, &type->s_vfs_rename_key); mutex_init(&s->s_dquot.dqio_mutex); - mutex_init(&s->s_dquot.dqonoff_mutex); s->s_maxbytes = MAX_NON_LFS; s->s_op = &default_op; s->s_time_gran = 1000000000; @@ -558,6 +557,13 @@ void drop_super(struct super_block *sb) EXPORT_SYMBOL(drop_super); +void drop_super_exclusive(struct super_block *sb) +{ + up_write(&sb->s_umount); + put_super(sb); +} +EXPORT_SYMBOL(drop_super_exclusive); + /** * iterate_supers - call function for all active superblocks * @f: function to call @@ -628,15 +634,7 @@ void iterate_supers_type(struct file_system_type *type, EXPORT_SYMBOL(iterate_supers_type); -/** - * get_super - get the superblock of a device - * @bdev: device to get the superblock for - * - * Scans the superblock list and finds the superblock of the file system - * mounted on the device given. %NULL is returned if no match is found. - */ - -struct super_block *get_super(struct block_device *bdev) +static struct super_block *__get_super(struct block_device *bdev, bool excl) { struct super_block *sb; @@ -651,11 +649,17 @@ rescan: if (sb->s_bdev == bdev) { sb->s_count++; spin_unlock(&sb_lock); - down_read(&sb->s_umount); + if (!excl) + down_read(&sb->s_umount); + else + down_write(&sb->s_umount); /* still alive? */ if (sb->s_root && (sb->s_flags & MS_BORN)) return sb; - up_read(&sb->s_umount); + if (!excl) + up_read(&sb->s_umount); + else + up_write(&sb->s_umount); /* nope, got unmounted */ spin_lock(&sb_lock); __put_super(sb); @@ -666,32 +670,67 @@ rescan: return NULL; } -EXPORT_SYMBOL(get_super); - /** - * get_super_thawed - get thawed superblock of a device + * get_super - get the superblock of a device * @bdev: device to get the superblock for * * Scans the superblock list and finds the superblock of the file system - * mounted on the device. The superblock is returned once it is thawed - * (or immediately if it was not frozen). %NULL is returned if no match - * is found. + * mounted on the device given. %NULL is returned if no match is found. */ -struct super_block *get_super_thawed(struct block_device *bdev) +struct super_block *get_super(struct block_device *bdev) +{ + return __get_super(bdev, false); +} +EXPORT_SYMBOL(get_super); + +static struct super_block *__get_super_thawed(struct block_device *bdev, + bool excl) { while (1) { - struct super_block *s = get_super(bdev); + struct super_block *s = __get_super(bdev, excl); if (!s || s->s_writers.frozen == SB_UNFROZEN) return s; - up_read(&s->s_umount); + if (!excl) + up_read(&s->s_umount); + else + up_write(&s->s_umount); wait_event(s->s_writers.wait_unfrozen, s->s_writers.frozen == SB_UNFROZEN); put_super(s); } } + +/** + * get_super_thawed - get thawed superblock of a device + * @bdev: device to get the superblock for + * + * Scans the superblock list and finds the superblock of the file system + * mounted on the device. The superblock is returned once it is thawed + * (or immediately if it was not frozen). %NULL is returned if no match + * is found. + */ +struct super_block *get_super_thawed(struct block_device *bdev) +{ + return __get_super_thawed(bdev, false); +} EXPORT_SYMBOL(get_super_thawed); /** + * get_super_exclusive_thawed - get thawed superblock of a device + * @bdev: device to get the superblock for + * + * Scans the superblock list and finds the superblock of the file system + * mounted on the device. The superblock is returned once it is thawed + * (or immediately if it was not frozen) and s_umount semaphore is held + * in exclusive mode. %NULL is returned if no match is found. + */ +struct super_block *get_super_exclusive_thawed(struct block_device *bdev) +{ + return __get_super_thawed(bdev, true); +} +EXPORT_SYMBOL(get_super_exclusive_thawed); + +/** * get_active_super - get an active reference to the superblock of a device * @bdev: device to get the superblock for * diff --git a/include/linux/fs.h b/include/linux/fs.h index e6e4146bf9ae..2ba074328894 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2903,8 +2903,10 @@ extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); extern struct super_block *get_super(struct block_device *); extern struct super_block *get_super_thawed(struct block_device *); +extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev); extern struct super_block *get_active_super(struct block_device *bdev); extern void drop_super(struct super_block *sb); +extern void drop_super_exclusive(struct super_block *sb); extern void iterate_supers(void (*)(struct super_block *, void *), void *); extern void iterate_supers_type(struct file_system_type *, void (*)(struct super_block *, void *), void *); diff --git a/include/linux/quota.h b/include/linux/quota.h index 78a98821f9d0..3434eef2a5aa 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -520,7 +520,6 @@ static inline void quota_send_warning(struct kqid qid, dev_t dev, struct quota_info { unsigned int flags; /* Flags for diskquotas on this device */ struct mutex dqio_mutex; /* lock device while I/O in progress */ - struct mutex dqonoff_mutex; /* Serialize quotaon & quotaoff */ struct inode *files[MAXQUOTAS]; /* inodes of quotafiles */ struct mem_dqinfo info[MAXQUOTAS]; /* Information for each quota type */ const struct quota_format_ops *ops[MAXQUOTAS]; /* Operations for each type */ |
