mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-24 01:20:52 +07:00
vfs: spread struct mount - work with counters
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
parent
a73324da7a
commit
83adc75322
124
fs/namespace.c
124
fs/namespace.c
@ -141,13 +141,13 @@ void mnt_release_group_id(struct mount *mnt)
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/*
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* vfsmount lock must be held for read
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*/
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static inline void mnt_add_count(struct vfsmount *mnt, int n)
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static inline void mnt_add_count(struct mount *mnt, int n)
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{
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#ifdef CONFIG_SMP
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this_cpu_add(mnt->mnt_pcp->mnt_count, n);
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this_cpu_add(mnt->mnt.mnt_pcp->mnt_count, n);
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#else
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preempt_disable();
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mnt->mnt_count += n;
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mnt->mnt.mnt_count += n;
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preempt_enable();
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#endif
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}
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@ -155,19 +155,19 @@ static inline void mnt_add_count(struct vfsmount *mnt, int n)
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/*
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* vfsmount lock must be held for write
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*/
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unsigned int mnt_get_count(struct vfsmount *mnt)
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unsigned int mnt_get_count(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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unsigned int count = 0;
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int cpu;
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for_each_possible_cpu(cpu) {
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count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_count;
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count += per_cpu_ptr(mnt->mnt.mnt_pcp, cpu)->mnt_count;
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}
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return count;
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#else
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return mnt->mnt_count;
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return mnt->mnt.mnt_count;
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#endif
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}
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@ -253,32 +253,32 @@ int __mnt_is_readonly(struct vfsmount *mnt)
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}
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EXPORT_SYMBOL_GPL(__mnt_is_readonly);
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static inline void mnt_inc_writers(struct vfsmount *mnt)
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static inline void mnt_inc_writers(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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this_cpu_inc(mnt->mnt_pcp->mnt_writers);
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this_cpu_inc(mnt->mnt.mnt_pcp->mnt_writers);
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#else
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mnt->mnt_writers++;
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mnt->mnt.mnt_writers++;
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#endif
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}
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static inline void mnt_dec_writers(struct vfsmount *mnt)
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static inline void mnt_dec_writers(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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this_cpu_dec(mnt->mnt_pcp->mnt_writers);
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this_cpu_dec(mnt->mnt.mnt_pcp->mnt_writers);
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#else
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mnt->mnt_writers--;
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mnt->mnt.mnt_writers--;
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#endif
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}
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static unsigned int mnt_get_writers(struct vfsmount *mnt)
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static unsigned int mnt_get_writers(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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unsigned int count = 0;
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int cpu;
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for_each_possible_cpu(cpu) {
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count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_writers;
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count += per_cpu_ptr(mnt->mnt.mnt_pcp, cpu)->mnt_writers;
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}
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return count;
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@ -297,7 +297,7 @@ static unsigned int mnt_get_writers(struct vfsmount *mnt)
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*/
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/**
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* mnt_want_write - get write access to a mount
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* @mnt: the mount on which to take a write
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* @m: the mount on which to take a write
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*
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* This tells the low-level filesystem that a write is
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* about to be performed to it, and makes sure that
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@ -305,8 +305,9 @@ static unsigned int mnt_get_writers(struct vfsmount *mnt)
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* the write operation is finished, mnt_drop_write()
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* must be called. This is effectively a refcount.
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*/
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int mnt_want_write(struct vfsmount *mnt)
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int mnt_want_write(struct vfsmount *m)
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{
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struct mount *mnt = real_mount(m);
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int ret = 0;
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preempt_disable();
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@ -317,7 +318,7 @@ int mnt_want_write(struct vfsmount *mnt)
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* incremented count after it has set MNT_WRITE_HOLD.
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*/
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smp_mb();
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while (mnt->mnt_flags & MNT_WRITE_HOLD)
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while (mnt->mnt.mnt_flags & MNT_WRITE_HOLD)
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cpu_relax();
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/*
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* After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
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@ -325,7 +326,7 @@ int mnt_want_write(struct vfsmount *mnt)
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* MNT_WRITE_HOLD is cleared.
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*/
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smp_rmb();
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if (__mnt_is_readonly(mnt)) {
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if (__mnt_is_readonly(m)) {
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mnt_dec_writers(mnt);
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ret = -EROFS;
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goto out;
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@ -354,7 +355,7 @@ int mnt_clone_write(struct vfsmount *mnt)
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if (__mnt_is_readonly(mnt))
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return -EROFS;
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preempt_disable();
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mnt_inc_writers(mnt);
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mnt_inc_writers(real_mount(mnt));
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preempt_enable();
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return 0;
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}
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@ -388,7 +389,7 @@ EXPORT_SYMBOL_GPL(mnt_want_write_file);
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void mnt_drop_write(struct vfsmount *mnt)
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{
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preempt_disable();
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mnt_dec_writers(mnt);
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mnt_dec_writers(real_mount(mnt));
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preempt_enable();
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}
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EXPORT_SYMBOL_GPL(mnt_drop_write);
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@ -399,12 +400,12 @@ void mnt_drop_write_file(struct file *file)
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}
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EXPORT_SYMBOL(mnt_drop_write_file);
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static int mnt_make_readonly(struct vfsmount *mnt)
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static int mnt_make_readonly(struct mount *mnt)
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{
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int ret = 0;
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br_write_lock(vfsmount_lock);
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mnt->mnt_flags |= MNT_WRITE_HOLD;
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mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
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/*
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* After storing MNT_WRITE_HOLD, we'll read the counters. This store
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* should be visible before we do.
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@ -430,21 +431,21 @@ static int mnt_make_readonly(struct vfsmount *mnt)
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if (mnt_get_writers(mnt) > 0)
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ret = -EBUSY;
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else
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mnt->mnt_flags |= MNT_READONLY;
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mnt->mnt.mnt_flags |= MNT_READONLY;
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/*
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* MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers
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* that become unheld will see MNT_READONLY.
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*/
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smp_wmb();
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mnt->mnt_flags &= ~MNT_WRITE_HOLD;
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mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
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br_write_unlock(vfsmount_lock);
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return ret;
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}
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static void __mnt_unmake_readonly(struct vfsmount *mnt)
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static void __mnt_unmake_readonly(struct mount *mnt)
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{
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br_write_lock(vfsmount_lock);
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mnt->mnt_flags &= ~MNT_READONLY;
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mnt->mnt.mnt_flags &= ~MNT_READONLY;
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br_write_unlock(vfsmount_lock);
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}
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@ -590,18 +591,18 @@ static void attach_mnt(struct mount *mnt, struct path *path)
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list_add_tail(&mnt->mnt.mnt_child, &path->mnt->mnt_mounts);
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}
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static inline void __mnt_make_longterm(struct vfsmount *mnt)
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static inline void __mnt_make_longterm(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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atomic_inc(&mnt->mnt_longterm);
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atomic_inc(&mnt->mnt.mnt_longterm);
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#endif
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}
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/* needs vfsmount lock for write */
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static inline void __mnt_make_shortterm(struct vfsmount *mnt)
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static inline void __mnt_make_shortterm(struct mount *mnt)
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{
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#ifdef CONFIG_SMP
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atomic_dec(&mnt->mnt_longterm);
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atomic_dec(&mnt->mnt.mnt_longterm);
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#endif
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}
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@ -611,15 +612,15 @@ static inline void __mnt_make_shortterm(struct vfsmount *mnt)
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static void commit_tree(struct mount *mnt)
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{
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struct mount *parent = mnt->mnt_parent;
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struct vfsmount *m;
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struct mount *m;
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LIST_HEAD(head);
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struct mnt_namespace *n = parent->mnt.mnt_ns;
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BUG_ON(parent == mnt);
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list_add_tail(&head, &mnt->mnt.mnt_list);
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list_for_each_entry(m, &head, mnt_list) {
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m->mnt_ns = n;
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list_for_each_entry(m, &head, mnt.mnt_list) {
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m->mnt.mnt_ns = n;
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__mnt_make_longterm(m);
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}
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@ -740,9 +741,10 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
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return NULL;
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}
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static inline void mntfree(struct vfsmount *mnt)
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static inline void mntfree(struct mount *mnt)
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{
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struct super_block *sb = mnt->mnt_sb;
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struct vfsmount *m = &mnt->mnt;
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struct super_block *sb = m->mnt_sb;
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/*
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* This probably indicates that somebody messed
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@ -755,18 +757,19 @@ static inline void mntfree(struct vfsmount *mnt)
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* so mnt_get_writers() below is safe.
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*/
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WARN_ON(mnt_get_writers(mnt));
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fsnotify_vfsmount_delete(mnt);
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dput(mnt->mnt_root);
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free_vfsmnt(real_mount(mnt));
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fsnotify_vfsmount_delete(m);
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dput(m->mnt_root);
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free_vfsmnt(mnt);
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deactivate_super(sb);
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}
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static void mntput_no_expire(struct vfsmount *mnt)
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static void mntput_no_expire(struct vfsmount *m)
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{
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struct mount *mnt = real_mount(m);
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put_again:
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#ifdef CONFIG_SMP
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br_read_lock(vfsmount_lock);
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if (likely(atomic_read(&mnt->mnt_longterm))) {
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if (likely(atomic_read(&mnt->mnt.mnt_longterm))) {
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mnt_add_count(mnt, -1);
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br_read_unlock(vfsmount_lock);
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return;
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@ -785,11 +788,11 @@ static void mntput_no_expire(struct vfsmount *mnt)
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return;
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br_write_lock(vfsmount_lock);
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#endif
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if (unlikely(mnt->mnt_pinned)) {
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mnt_add_count(mnt, mnt->mnt_pinned + 1);
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mnt->mnt_pinned = 0;
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if (unlikely(mnt->mnt.mnt_pinned)) {
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mnt_add_count(mnt, mnt->mnt.mnt_pinned + 1);
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mnt->mnt.mnt_pinned = 0;
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br_write_unlock(vfsmount_lock);
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acct_auto_close_mnt(mnt);
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acct_auto_close_mnt(m);
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goto put_again;
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}
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br_write_unlock(vfsmount_lock);
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@ -810,7 +813,7 @@ EXPORT_SYMBOL(mntput);
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struct vfsmount *mntget(struct vfsmount *mnt)
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{
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if (mnt)
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mnt_add_count(mnt, 1);
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mnt_add_count(real_mount(mnt), 1);
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return mnt;
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}
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EXPORT_SYMBOL(mntget);
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@ -827,7 +830,7 @@ void mnt_unpin(struct vfsmount *mnt)
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{
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br_write_lock(vfsmount_lock);
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if (mnt->mnt_pinned) {
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mnt_add_count(mnt, 1);
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mnt_add_count(real_mount(mnt), 1);
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mnt->mnt_pinned--;
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}
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br_write_unlock(vfsmount_lock);
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@ -1150,7 +1153,7 @@ int may_umount_tree(struct vfsmount *mnt)
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/* write lock needed for mnt_get_count */
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br_write_lock(vfsmount_lock);
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for (p = real_mount(mnt); p; p = next_mnt(p, mnt)) {
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actual_refs += mnt_get_count(&p->mnt);
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actual_refs += mnt_get_count(p);
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minimum_refs += 2;
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}
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br_write_unlock(vfsmount_lock);
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@ -1234,7 +1237,7 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill)
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list_del_init(&p->mnt.mnt_list);
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__touch_mnt_namespace(p->mnt.mnt_ns);
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p->mnt.mnt_ns = NULL;
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__mnt_make_shortterm(&p->mnt);
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__mnt_make_shortterm(p);
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list_del_init(&p->mnt.mnt_child);
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if (mnt_has_parent(p)) {
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p->mnt_parent->mnt.mnt_ghosts++;
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@ -1273,7 +1276,7 @@ static int do_umount(struct mount *mnt, int flags)
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* all race cases, but it's a slowpath.
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*/
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br_write_lock(vfsmount_lock);
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if (mnt_get_count(&mnt->mnt) != 2) {
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if (mnt_get_count(mnt) != 2) {
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br_write_unlock(vfsmount_lock);
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return -EBUSY;
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}
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@ -1798,9 +1801,9 @@ static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
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return 0;
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if (readonly_request)
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error = mnt_make_readonly(mnt);
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error = mnt_make_readonly(real_mount(mnt));
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else
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__mnt_unmake_readonly(mnt);
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__mnt_unmake_readonly(real_mount(mnt));
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return error;
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}
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@ -2034,7 +2037,7 @@ int finish_automount(struct vfsmount *m, struct path *path)
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/* The new mount record should have at least 2 refs to prevent it being
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* expired before we get a chance to add it
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*/
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BUG_ON(mnt_get_count(m) < 2);
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BUG_ON(mnt_get_count(real_mount(m)) < 2);
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if (m->mnt_sb == path->mnt->mnt_sb &&
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m->mnt_root == path->dentry) {
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@ -2365,16 +2368,17 @@ static struct mnt_namespace *alloc_mnt_ns(void)
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void mnt_make_longterm(struct vfsmount *mnt)
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{
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__mnt_make_longterm(mnt);
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__mnt_make_longterm(real_mount(mnt));
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}
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void mnt_make_shortterm(struct vfsmount *mnt)
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void mnt_make_shortterm(struct vfsmount *m)
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{
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#ifdef CONFIG_SMP
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if (atomic_add_unless(&mnt->mnt_longterm, -1, 1))
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struct mount *mnt = real_mount(m);
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if (atomic_add_unless(&mnt->mnt.mnt_longterm, -1, 1))
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return;
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br_write_lock(vfsmount_lock);
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atomic_dec(&mnt->mnt_longterm);
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atomic_dec(&mnt->mnt.mnt_longterm);
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br_write_unlock(vfsmount_lock);
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#endif
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}
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@ -2418,17 +2422,17 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
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q = new;
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while (p) {
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q->mnt.mnt_ns = new_ns;
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__mnt_make_longterm(&q->mnt);
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__mnt_make_longterm(q);
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if (fs) {
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if (&p->mnt == fs->root.mnt) {
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fs->root.mnt = mntget(&q->mnt);
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__mnt_make_longterm(&q->mnt);
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__mnt_make_longterm(q);
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mnt_make_shortterm(&p->mnt);
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rootmnt = &p->mnt;
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}
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if (&p->mnt == fs->pwd.mnt) {
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fs->pwd.mnt = mntget(&q->mnt);
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__mnt_make_longterm(&q->mnt);
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__mnt_make_longterm(q);
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mnt_make_shortterm(&p->mnt);
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pwdmnt = &p->mnt;
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}
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@ -2474,7 +2478,7 @@ static struct mnt_namespace *create_mnt_ns(struct vfsmount *mnt)
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new_ns = alloc_mnt_ns();
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if (!IS_ERR(new_ns)) {
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mnt->mnt_ns = new_ns;
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__mnt_make_longterm(mnt);
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__mnt_make_longterm(real_mount(mnt));
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new_ns->root = mnt;
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list_add(&new_ns->list, &new_ns->root->mnt_list);
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} else {
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@ -274,7 +274,7 @@ int propagate_mnt(struct vfsmount *dest_mnt, struct dentry *dest_dentry,
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*/
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static inline int do_refcount_check(struct mount *mnt, int count)
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{
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int mycount = mnt_get_count(&mnt->mnt) - mnt->mnt.mnt_ghosts;
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int mycount = mnt_get_count(mnt) - mnt->mnt.mnt_ghosts;
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return (mycount > count);
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}
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@ -36,7 +36,7 @@ int propagate_umount(struct list_head *);
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int propagate_mount_busy(struct mount *, int);
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void mnt_release_group_id(struct mount *);
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int get_dominating_id(struct vfsmount *mnt, const struct path *root);
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unsigned int mnt_get_count(struct vfsmount *mnt);
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unsigned int mnt_get_count(struct mount *mnt);
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void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
|
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struct mount *);
|
||||
void release_mounts(struct list_head *);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user