Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756193Ab3JCGTa (ORCPT ); Thu, 3 Oct 2013 02:19:30 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:41562 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753931Ab3JCGT1 (ORCPT ); Thu, 3 Oct 2013 02:19:27 -0400 Date: Thu, 03 Oct 2013 07:19:26 +0100 To: torvalds@linux-foundation.org Subject: [PATCH 12/17] new helpers: lock_mount_hash/unlock_mount_hash Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: From: Al Viro Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11676 Lines: 429 aka br_write_{lock,unlock} of vfsmount_lock. Inlines in fs/mount.h, vfsmount_lock extern moved over there as well. Signed-off-by: Al Viro --- fs/internal.h | 4 -- fs/mount.h | 13 +++++++ fs/namespace.c | 96 ++++++++++++++++++++++++++++---------------------------- fs/pnode.c | 4 +- 4 files changed, 63 insertions(+), 54 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 513e0d8..4a11e75 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -9,8 +9,6 @@ * 2 of the License, or (at your option) any later version. */ -#include - struct super_block; struct file_system_type; struct linux_binprm; @@ -62,8 +60,6 @@ extern int sb_prepare_remount_readonly(struct super_block *); extern void __init mnt_init(void); -extern struct lglock vfsmount_lock; - extern int __mnt_want_write(struct vfsmount *); extern int __mnt_want_write_file(struct file *); extern void __mnt_drop_write(struct vfsmount *); diff --git a/fs/mount.h b/fs/mount.h index 3168dc4..7076f25 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -1,6 +1,7 @@ #include #include #include +#include struct mnt_namespace { atomic_t count; @@ -83,6 +84,18 @@ static inline void get_mnt_ns(struct mnt_namespace *ns) atomic_inc(&ns->count); } +extern struct lglock vfsmount_lock; + +static inline void lock_mount_hash(void) +{ + br_write_lock(&vfsmount_lock); +} + +static inline void unlock_mount_hash(void) +{ + br_write_unlock(&vfsmount_lock); +} + struct proc_mounts { struct seq_file m; struct mnt_namespace *ns; diff --git a/fs/namespace.c b/fs/namespace.c index 6985d52..aa6dd93 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -456,7 +456,7 @@ static int mnt_make_readonly(struct mount *mnt) { int ret = 0; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); mnt->mnt.mnt_flags |= MNT_WRITE_HOLD; /* * After storing MNT_WRITE_HOLD, we'll read the counters. This store @@ -490,15 +490,15 @@ static int mnt_make_readonly(struct mount *mnt) */ smp_wmb(); mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return ret; } static void __mnt_unmake_readonly(struct mount *mnt) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); mnt->mnt.mnt_flags &= ~MNT_READONLY; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } int sb_prepare_remount_readonly(struct super_block *sb) @@ -510,7 +510,7 @@ int sb_prepare_remount_readonly(struct super_block *sb) if (atomic_long_read(&sb->s_remove_count)) return -EBUSY; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); list_for_each_entry(mnt, &sb->s_mounts, mnt_instance) { if (!(mnt->mnt.mnt_flags & MNT_READONLY)) { mnt->mnt.mnt_flags |= MNT_WRITE_HOLD; @@ -532,7 +532,7 @@ int sb_prepare_remount_readonly(struct super_block *sb) if (mnt->mnt.mnt_flags & MNT_WRITE_HOLD) mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD; } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return err; } @@ -794,9 +794,9 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void mnt->mnt.mnt_sb = root->d_sb; mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); list_add_tail(&mnt->mnt_instance, &root->d_sb->s_mounts); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return &mnt->mnt; } EXPORT_SYMBOL_GPL(vfs_kern_mount); @@ -837,9 +837,9 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root, mnt->mnt.mnt_root = dget(root); mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); list_add_tail(&mnt->mnt_instance, &sb->s_mounts); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); if ((flag & CL_SLAVE) || ((flag & CL_SHARED_TO_SLAVE) && IS_MNT_SHARED(old))) { @@ -883,28 +883,28 @@ put_again: } br_read_unlock(&vfsmount_lock); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); mnt_add_count(mnt, -1); if (mnt_get_count(mnt)) { - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return; } #else mnt_add_count(mnt, -1); if (likely(mnt_get_count(mnt))) return; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); #endif if (unlikely(mnt->mnt_pinned)) { mnt_add_count(mnt, mnt->mnt_pinned + 1); mnt->mnt_pinned = 0; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); acct_auto_close_mnt(&mnt->mnt); goto put_again; } list_del(&mnt->mnt_instance); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); /* * This probably indicates that somebody messed @@ -945,21 +945,21 @@ EXPORT_SYMBOL(mntget); void mnt_pin(struct vfsmount *mnt) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); real_mount(mnt)->mnt_pinned++; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } EXPORT_SYMBOL(mnt_pin); void mnt_unpin(struct vfsmount *m) { struct mount *mnt = real_mount(m); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); if (mnt->mnt_pinned) { mnt_add_count(mnt, 1); mnt->mnt_pinned--; } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } EXPORT_SYMBOL(mnt_unpin); @@ -1076,12 +1076,12 @@ int may_umount_tree(struct vfsmount *m) BUG_ON(!m); /* write lock needed for mnt_get_count */ - br_write_lock(&vfsmount_lock); + lock_mount_hash(); for (p = mnt; p; p = next_mnt(p, mnt)) { actual_refs += mnt_get_count(p); minimum_refs += 2; } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); if (actual_refs > minimum_refs) return 0; @@ -1108,10 +1108,10 @@ int may_umount(struct vfsmount *mnt) { int ret = 1; down_read(&namespace_sem); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); if (propagate_mount_busy(real_mount(mnt), 2)) ret = 0; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); up_read(&namespace_sem); return ret; } @@ -1208,12 +1208,12 @@ static int do_umount(struct mount *mnt, int flags) * probably don't strictly need the lock here if we examined * all race cases, but it's a slowpath. */ - br_write_lock(&vfsmount_lock); + lock_mount_hash(); if (mnt_get_count(mnt) != 2) { - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return -EBUSY; } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); if (!xchg(&mnt->mnt_expiry_mark, 1)) return -EAGAIN; @@ -1255,7 +1255,7 @@ static int do_umount(struct mount *mnt, int flags) } namespace_lock(); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); event++; if (!(flags & MNT_DETACH)) @@ -1267,7 +1267,7 @@ static int do_umount(struct mount *mnt, int flags) umount_tree(mnt, 1); retval = 0; } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); namespace_unlock(); return retval; } @@ -1410,18 +1410,18 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry, q = clone_mnt(p, p->mnt.mnt_root, flag); if (IS_ERR(q)) goto out; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); list_add_tail(&q->mnt_list, &res->mnt_list); attach_mnt(q, parent, p->mnt_mp); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } } return res; out: if (res) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); umount_tree(res, 0); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } return q; } @@ -1443,9 +1443,9 @@ struct vfsmount *collect_mounts(struct path *path) void drop_collected_mounts(struct vfsmount *mnt) { namespace_lock(); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); umount_tree(real_mount(mnt), 0); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); namespace_unlock(); } @@ -1572,7 +1572,7 @@ static int attach_recursive_mnt(struct mount *source_mnt, if (err) goto out_cleanup_ids; - br_write_lock(&vfsmount_lock); + lock_mount_hash(); if (IS_MNT_SHARED(dest_mnt)) { for (p = source_mnt; p; p = next_mnt(p, source_mnt)) @@ -1591,7 +1591,7 @@ static int attach_recursive_mnt(struct mount *source_mnt, list_del_init(&child->mnt_hash); commit_tree(child); } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return 0; @@ -1693,10 +1693,10 @@ static int do_change_type(struct path *path, int flag) goto out_unlock; } - br_write_lock(&vfsmount_lock); + lock_mount_hash(); for (m = mnt; m; m = (recurse ? next_mnt(m, mnt) : NULL)) change_mnt_propagation(m, type); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); out_unlock: namespace_unlock(); @@ -1768,9 +1768,9 @@ static int do_loopback(struct path *path, const char *old_name, err = graft_tree(mnt, parent, mp); if (err) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); umount_tree(mnt, 0); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } out2: unlock_mount(mp); @@ -1829,11 +1829,11 @@ static int do_remount(struct path *path, int flags, int mnt_flags, else err = do_remount_sb(sb, flags, data, 0); if (!err) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); mnt_flags |= mnt->mnt.mnt_flags & MNT_PROPAGATION_MASK; mnt->mnt.mnt_flags = mnt_flags; touch_mnt_namespace(mnt->mnt_ns); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); } up_write(&sb->s_umount); return err; @@ -2093,7 +2093,7 @@ void mark_mounts_for_expiry(struct list_head *mounts) return; namespace_lock(); - br_write_lock(&vfsmount_lock); + lock_mount_hash(); /* extract from the expiration list every vfsmount that matches the * following criteria: @@ -2112,7 +2112,7 @@ void mark_mounts_for_expiry(struct list_head *mounts) touch_mnt_namespace(mnt->mnt_ns); umount_tree(mnt, 1); } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); namespace_unlock(); } @@ -2662,7 +2662,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, if (!is_path_reachable(old_mnt, old.dentry, &new)) goto out4; root_mp->m_count++; /* pin it so it won't go away */ - br_write_lock(&vfsmount_lock); + lock_mount_hash(); detach_mnt(new_mnt, &parent_path); detach_mnt(root_mnt, &root_parent); if (root_mnt->mnt.mnt_flags & MNT_LOCKED) { @@ -2674,7 +2674,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, /* mount new_root on / */ attach_mnt(new_mnt, real_mount(root_parent.mnt), root_mp); touch_mnt_namespace(current->nsproxy->mnt_ns); - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); chroot_fs_refs(&root, &new); put_mountpoint(root_mp); error = 0; @@ -2788,9 +2788,9 @@ void kern_unmount(struct vfsmount *mnt) { /* release long term mount so mount point can be released */ if (!IS_ERR_OR_NULL(mnt)) { - br_write_lock(&vfsmount_lock); + lock_mount_hash(); real_mount(mnt)->mnt_ns = NULL; - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); mntput(mnt); } } diff --git a/fs/pnode.c b/fs/pnode.c index 3cfd48c..58933fd 100644 --- a/fs/pnode.c +++ b/fs/pnode.c @@ -264,12 +264,12 @@ int propagate_mnt(struct mount *dest_mnt, struct mountpoint *dest_mp, prev_src_mnt = child; } out: - br_write_lock(&vfsmount_lock); + lock_mount_hash(); while (!list_empty(&tmp_list)) { child = list_first_entry(&tmp_list, struct mount, mnt_hash); umount_tree(child, 0); } - br_write_unlock(&vfsmount_lock); + unlock_mount_hash(); return ret; } -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/