[v5] kvm: Refactor handling of VM debugfs files
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Message ID 20191213130721.7942-1-milanpa@amazon.de
State New
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Series
  • [v5] kvm: Refactor handling of VM debugfs files
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Commit Message

Milan Pandurov Dec. 13, 2019, 1:07 p.m. UTC
We can store reference to kvm_stats_debugfs_item instead of copying
its values to kvm_stat_data.
This allows us to remove duplicated code and usage of temporary
kvm_stat_data inside vm_stat_get et al.

Signed-off-by: Milan Pandurov <milanpa@amazon.de>
Reviewed-by: Alexander Graf <graf@anazon.com>

---
v1 -> v2:
 - fix compile issues
 - add reference to kvm_stats_debugfs_item in kvm_stat_data
 - return -EINVAL when writing !0
 - use explicit switch case instead of ops indirection
 - fix checkpatch warning: Change S_IWUGO to 0222

v2 -> v3:
 - remove unused kvm_stat_ops
 - fix style issues

v3 -> v4:
 - revert: Change S_IWUGO to 0222

v4 -> v5:
 - fix checkpatch warning: Change S_IWUGO to 0222
---
 include/linux/kvm_host.h |   7 +-
 virt/kvm/kvm_main.c      | 142 +++++++++++++++++++--------------------
 2 files changed, 76 insertions(+), 73 deletions(-)

Comments

Graf (AWS), Alexander Dec. 13, 2019, 1:28 p.m. UTC | #1
> Am 13.12.2019 um 14:07 schrieb Pandurov, Milan <milanpa@amazon.de>:
> 
> ´╗┐We can store reference to kvm_stats_debugfs_item instead of copying
> its values to kvm_stat_data.
> This allows us to remove duplicated code and usage of temporary
> kvm_stat_data inside vm_stat_get et al.
> 
> Signed-off-by: Milan Pandurov <milanpa@amazon.de>
> Reviewed-by: Alexander Graf <graf@anazon.com>

If there are no further comments could whoever applies this please fix my typo? :)


Thanks,

Alex




Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Ralf Herbrich
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
Christian Borntraeger Dec. 13, 2019, 2:35 p.m. UTC | #2
On 13.12.19 14:07, Milan Pandurov wrote:
> We can store reference to kvm_stats_debugfs_item instead of copying
> its values to kvm_stat_data.
> This allows us to remove duplicated code and usage of temporary
> kvm_stat_data inside vm_stat_get et al.
> 
> Signed-off-by: Milan Pandurov <milanpa@amazon.de>
> Reviewed-by: Alexander Graf <graf@anazon.com>
> 

I gave this a quick spin and it still seems to work.

> ---
> v1 -> v2:
>  - fix compile issues
>  - add reference to kvm_stats_debugfs_item in kvm_stat_data
>  - return -EINVAL when writing !0
>  - use explicit switch case instead of ops indirection
>  - fix checkpatch warning: Change S_IWUGO to 0222
> 
> v2 -> v3:
>  - remove unused kvm_stat_ops
>  - fix style issues
> 
> v3 -> v4:
>  - revert: Change S_IWUGO to 0222
> 
> v4 -> v5:
>  - fix checkpatch warning: Change S_IWUGO to 0222
> ---
>  include/linux/kvm_host.h |   7 +-
>  virt/kvm/kvm_main.c      | 142 +++++++++++++++++++--------------------
>  2 files changed, 76 insertions(+), 73 deletions(-)
> 
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 7ed1e2f8641e..d3f2c0eae857 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1109,9 +1109,8 @@ enum kvm_stat_kind {
>  };
>  
>  struct kvm_stat_data {
> -	int offset;
> -	int mode;
>  	struct kvm *kvm;
> +	struct kvm_stats_debugfs_item *dbgfs_item;
>  };
>  
>  struct kvm_stats_debugfs_item {
> @@ -1120,6 +1119,10 @@ struct kvm_stats_debugfs_item {
>  	enum kvm_stat_kind kind;
>  	int mode;
>  };
> +
> +#define KVM_DBGFS_GET_MODE(dbgfs_item)                                         \
> +	((dbgfs_item)->mode ? (dbgfs_item)->mode : 0644)
> +
>  extern struct kvm_stats_debugfs_item debugfs_entries[];
>  extern struct dentry *kvm_debugfs_dir;
>  
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 00268290dcbd..0ebd6aa95671 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -113,7 +113,7 @@ struct dentry *kvm_debugfs_dir;
>  EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
>  
>  static int kvm_debugfs_num_entries;
> -static const struct file_operations *stat_fops_per_vm[];
> +static const struct file_operations stat_fops_per_vm;
>  
>  static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
>  			   unsigned long arg);
> @@ -650,11 +650,11 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
>  			return -ENOMEM;
>  
>  		stat_data->kvm = kvm;
> -		stat_data->offset = p->offset;
> -		stat_data->mode = p->mode ? p->mode : 0644;
> +		stat_data->dbgfs_item = p;
>  		kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
> -		debugfs_create_file(p->name, stat_data->mode, kvm->debugfs_dentry,
> -				    stat_data, stat_fops_per_vm[p->kind]);
> +		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> +				    kvm->debugfs_dentry, stat_data,
> +				    &stat_fops_per_vm);
>  	}
>  	return 0;
>  }
> @@ -4013,8 +4013,9 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file,
>  		return -ENOENT;
>  
>  	if (simple_attr_open(inode, file, get,
> -			     stat_data->mode & S_IWUGO ? set : NULL,
> -			     fmt)) {
> +		    KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & 0222
> +		    ? set : NULL,
> +		    fmt)) {
>  		kvm_put_kvm(stat_data->kvm);
>  		return -ENOMEM;
>  	}
> @@ -4033,105 +4034,111 @@ static int kvm_debugfs_release(struct inode *inode, struct file *file)
>  	return 0;
>  }
>  
> -static int vm_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
>  {
> -	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> +	*val = *(ulong *)((void *)kvm + offset);
>  
> -	*val = *(ulong *)((void *)stat_data->kvm + stat_data->offset);
> +	return 0;
> +}
> +
> +static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
> +{
> +	*(ulong *)((void *)kvm + offset) = 0;
>  
>  	return 0;
>  }
>  
> -static int vm_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
>  {
> -	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> +	int i;
> +	struct kvm_vcpu *vcpu;
>  
> -	if (val)
> -		return -EINVAL;
> +	*val = 0;
>  
> -	*(ulong *)((void *)stat_data->kvm + stat_data->offset) = 0;
> +	kvm_for_each_vcpu(i, vcpu, kvm)
> +		*val += *(u64 *)((void *)vcpu + offset);
>  
>  	return 0;
>  }
>  
> -static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
>  {
> -	__simple_attr_check_format("%llu\n", 0ull);
> -	return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
> -				vm_stat_clear_per_vm, "%llu\n");
> -}
> +	int i;
> +	struct kvm_vcpu *vcpu;
>  
> -static const struct file_operations vm_stat_get_per_vm_fops = {
> -	.owner   = THIS_MODULE,
> -	.open    = vm_stat_get_per_vm_open,
> -	.release = kvm_debugfs_release,
> -	.read    = simple_attr_read,
> -	.write   = simple_attr_write,
> -	.llseek  = no_llseek,
> -};
> +	kvm_for_each_vcpu(i, vcpu, kvm)
> +		*(u64 *)((void *)vcpu + offset) = 0;
> +
> +	return 0;
> +}
>  
> -static int vcpu_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_stat_data_get(void *data, u64 *val)
>  {
> -	int i;
> +	int r = -EFAULT;
>  	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> -	struct kvm_vcpu *vcpu;
> -
> -	*val = 0;
>  
> -	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> -		*val += *(u64 *)((void *)vcpu + stat_data->offset);
> +	switch (stat_data->dbgfs_item->kind) {
> +	case KVM_STAT_VM:
> +		r = kvm_get_stat_per_vm(stat_data->kvm,
> +					stat_data->dbgfs_item->offset, val);
> +		break;
> +	case KVM_STAT_VCPU:
> +		r = kvm_get_stat_per_vcpu(stat_data->kvm,
> +					  stat_data->dbgfs_item->offset, val);
> +		break;
> +	}
>  
> -	return 0;
> +	return r;
>  }
>  
> -static int vcpu_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_stat_data_clear(void *data, u64 val)
>  {
> -	int i;
> +	int r = -EFAULT;
>  	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> -	struct kvm_vcpu *vcpu;
>  
>  	if (val)
>  		return -EINVAL;
>  
> -	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> -		*(u64 *)((void *)vcpu + stat_data->offset) = 0;
> +	switch (stat_data->dbgfs_item->kind) {
> +	case KVM_STAT_VM:
> +		r = kvm_clear_stat_per_vm(stat_data->kvm,
> +					  stat_data->dbgfs_item->offset);
> +		break;
> +	case KVM_STAT_VCPU:
> +		r = kvm_clear_stat_per_vcpu(stat_data->kvm,
> +					    stat_data->dbgfs_item->offset);
> +		break;
> +	}
>  
> -	return 0;
> +	return r;
>  }
>  
> -static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_stat_data_open(struct inode *inode, struct file *file)
>  {
>  	__simple_attr_check_format("%llu\n", 0ull);
> -	return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
> -				 vcpu_stat_clear_per_vm, "%llu\n");
> +	return kvm_debugfs_open(inode, file, kvm_stat_data_get,
> +				kvm_stat_data_clear, "%llu\n");
>  }
>  
> -static const struct file_operations vcpu_stat_get_per_vm_fops = {
> -	.owner   = THIS_MODULE,
> -	.open    = vcpu_stat_get_per_vm_open,
> +static const struct file_operations stat_fops_per_vm = {
> +	.owner = THIS_MODULE,
> +	.open = kvm_stat_data_open,
>  	.release = kvm_debugfs_release,
> -	.read    = simple_attr_read,
> -	.write   = simple_attr_write,
> -	.llseek  = no_llseek,
> -};
> -
> -static const struct file_operations *stat_fops_per_vm[] = {
> -	[KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
> -	[KVM_STAT_VM]   = &vm_stat_get_per_vm_fops,
> +	.read = simple_attr_read,
> +	.write = simple_attr_write,
> +	.llseek = no_llseek,
>  };
>  
>  static int vm_stat_get(void *_offset, u64 *val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  	u64 tmp_val;
>  
>  	*val = 0;
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> +		kvm_get_stat_per_vm(kvm, offset, &tmp_val);
>  		*val += tmp_val;
>  	}
>  	mutex_unlock(&kvm_lock);
> @@ -4142,15 +4149,13 @@ static int vm_stat_clear(void *_offset, u64 val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  
>  	if (val)
>  		return -EINVAL;
>  
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vm_stat_clear_per_vm((void *)&stat_tmp, 0);
> +		kvm_clear_stat_per_vm(kvm, offset);
>  	}
>  	mutex_unlock(&kvm_lock);
>  
> @@ -4163,14 +4168,12 @@ static int vcpu_stat_get(void *_offset, u64 *val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  	u64 tmp_val;
>  
>  	*val = 0;
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> +		kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
>  		*val += tmp_val;
>  	}
>  	mutex_unlock(&kvm_lock);
> @@ -4181,15 +4184,13 @@ static int vcpu_stat_clear(void *_offset, u64 val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  
>  	if (val)
>  		return -EINVAL;
>  
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
> +		kvm_clear_stat_per_vcpu(kvm, offset);
>  	}
>  	mutex_unlock(&kvm_lock);
>  
> @@ -4262,9 +4263,8 @@ static void kvm_init_debug(void)
>  
>  	kvm_debugfs_num_entries = 0;
>  	for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
> -		int mode = p->mode ? p->mode : 0644;
> -		debugfs_create_file(p->name, mode, kvm_debugfs_dir,
> -				    (void *)(long)p->offset,
> +		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> +				    kvm_debugfs_dir, (void *)(long)p->offset,
>  				    stat_fops[p->kind]);
>  	}
>  }
>
Paolo Bonzini Jan. 17, 2020, 11:28 p.m. UTC | #3
On 13/12/19 14:07, Milan Pandurov wrote:
> We can store reference to kvm_stats_debugfs_item instead of copying
> its values to kvm_stat_data.
> This allows us to remove duplicated code and usage of temporary
> kvm_stat_data inside vm_stat_get et al.
> 
> Signed-off-by: Milan Pandurov <milanpa@amazon.de>
> Reviewed-by: Alexander Graf <graf@anazon.com>
> 
> ---
> v1 -> v2:
>  - fix compile issues
>  - add reference to kvm_stats_debugfs_item in kvm_stat_data
>  - return -EINVAL when writing !0
>  - use explicit switch case instead of ops indirection
>  - fix checkpatch warning: Change S_IWUGO to 0222
> 
> v2 -> v3:
>  - remove unused kvm_stat_ops
>  - fix style issues
> 
> v3 -> v4:
>  - revert: Change S_IWUGO to 0222
> 
> v4 -> v5:
>  - fix checkpatch warning: Change S_IWUGO to 0222
> ---
>  include/linux/kvm_host.h |   7 +-
>  virt/kvm/kvm_main.c      | 142 +++++++++++++++++++--------------------
>  2 files changed, 76 insertions(+), 73 deletions(-)
> 
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 7ed1e2f8641e..d3f2c0eae857 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1109,9 +1109,8 @@ enum kvm_stat_kind {
>  };
>  
>  struct kvm_stat_data {
> -	int offset;
> -	int mode;
>  	struct kvm *kvm;
> +	struct kvm_stats_debugfs_item *dbgfs_item;
>  };
>  
>  struct kvm_stats_debugfs_item {
> @@ -1120,6 +1119,10 @@ struct kvm_stats_debugfs_item {
>  	enum kvm_stat_kind kind;
>  	int mode;
>  };
> +
> +#define KVM_DBGFS_GET_MODE(dbgfs_item)                                         \
> +	((dbgfs_item)->mode ? (dbgfs_item)->mode : 0644)
> +
>  extern struct kvm_stats_debugfs_item debugfs_entries[];
>  extern struct dentry *kvm_debugfs_dir;
>  
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 00268290dcbd..0ebd6aa95671 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -113,7 +113,7 @@ struct dentry *kvm_debugfs_dir;
>  EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
>  
>  static int kvm_debugfs_num_entries;
> -static const struct file_operations *stat_fops_per_vm[];
> +static const struct file_operations stat_fops_per_vm;
>  
>  static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
>  			   unsigned long arg);
> @@ -650,11 +650,11 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
>  			return -ENOMEM;
>  
>  		stat_data->kvm = kvm;
> -		stat_data->offset = p->offset;
> -		stat_data->mode = p->mode ? p->mode : 0644;
> +		stat_data->dbgfs_item = p;
>  		kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
> -		debugfs_create_file(p->name, stat_data->mode, kvm->debugfs_dentry,
> -				    stat_data, stat_fops_per_vm[p->kind]);
> +		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> +				    kvm->debugfs_dentry, stat_data,
> +				    &stat_fops_per_vm);
>  	}
>  	return 0;
>  }
> @@ -4013,8 +4013,9 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file,
>  		return -ENOENT;
>  
>  	if (simple_attr_open(inode, file, get,
> -			     stat_data->mode & S_IWUGO ? set : NULL,
> -			     fmt)) {
> +		    KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & 0222
> +		    ? set : NULL,
> +		    fmt)) {
>  		kvm_put_kvm(stat_data->kvm);
>  		return -ENOMEM;
>  	}
> @@ -4033,105 +4034,111 @@ static int kvm_debugfs_release(struct inode *inode, struct file *file)
>  	return 0;
>  }
>  
> -static int vm_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
>  {
> -	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> +	*val = *(ulong *)((void *)kvm + offset);
>  
> -	*val = *(ulong *)((void *)stat_data->kvm + stat_data->offset);
> +	return 0;
> +}
> +
> +static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
> +{
> +	*(ulong *)((void *)kvm + offset) = 0;
>  
>  	return 0;
>  }
>  
> -static int vm_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
>  {
> -	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> +	int i;
> +	struct kvm_vcpu *vcpu;
>  
> -	if (val)
> -		return -EINVAL;
> +	*val = 0;
>  
> -	*(ulong *)((void *)stat_data->kvm + stat_data->offset) = 0;
> +	kvm_for_each_vcpu(i, vcpu, kvm)
> +		*val += *(u64 *)((void *)vcpu + offset);
>  
>  	return 0;
>  }
>  
> -static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
>  {
> -	__simple_attr_check_format("%llu\n", 0ull);
> -	return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
> -				vm_stat_clear_per_vm, "%llu\n");
> -}
> +	int i;
> +	struct kvm_vcpu *vcpu;
>  
> -static const struct file_operations vm_stat_get_per_vm_fops = {
> -	.owner   = THIS_MODULE,
> -	.open    = vm_stat_get_per_vm_open,
> -	.release = kvm_debugfs_release,
> -	.read    = simple_attr_read,
> -	.write   = simple_attr_write,
> -	.llseek  = no_llseek,
> -};
> +	kvm_for_each_vcpu(i, vcpu, kvm)
> +		*(u64 *)((void *)vcpu + offset) = 0;
> +
> +	return 0;
> +}
>  
> -static int vcpu_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_stat_data_get(void *data, u64 *val)
>  {
> -	int i;
> +	int r = -EFAULT;
>  	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> -	struct kvm_vcpu *vcpu;
> -
> -	*val = 0;
>  
> -	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> -		*val += *(u64 *)((void *)vcpu + stat_data->offset);
> +	switch (stat_data->dbgfs_item->kind) {
> +	case KVM_STAT_VM:
> +		r = kvm_get_stat_per_vm(stat_data->kvm,
> +					stat_data->dbgfs_item->offset, val);
> +		break;
> +	case KVM_STAT_VCPU:
> +		r = kvm_get_stat_per_vcpu(stat_data->kvm,
> +					  stat_data->dbgfs_item->offset, val);
> +		break;
> +	}
>  
> -	return 0;
> +	return r;
>  }
>  
> -static int vcpu_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_stat_data_clear(void *data, u64 val)
>  {
> -	int i;
> +	int r = -EFAULT;
>  	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> -	struct kvm_vcpu *vcpu;
>  
>  	if (val)
>  		return -EINVAL;
>  
> -	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> -		*(u64 *)((void *)vcpu + stat_data->offset) = 0;
> +	switch (stat_data->dbgfs_item->kind) {
> +	case KVM_STAT_VM:
> +		r = kvm_clear_stat_per_vm(stat_data->kvm,
> +					  stat_data->dbgfs_item->offset);
> +		break;
> +	case KVM_STAT_VCPU:
> +		r = kvm_clear_stat_per_vcpu(stat_data->kvm,
> +					    stat_data->dbgfs_item->offset);
> +		break;
> +	}
>  
> -	return 0;
> +	return r;
>  }
>  
> -static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_stat_data_open(struct inode *inode, struct file *file)
>  {
>  	__simple_attr_check_format("%llu\n", 0ull);
> -	return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
> -				 vcpu_stat_clear_per_vm, "%llu\n");
> +	return kvm_debugfs_open(inode, file, kvm_stat_data_get,
> +				kvm_stat_data_clear, "%llu\n");
>  }
>  
> -static const struct file_operations vcpu_stat_get_per_vm_fops = {
> -	.owner   = THIS_MODULE,
> -	.open    = vcpu_stat_get_per_vm_open,
> +static const struct file_operations stat_fops_per_vm = {
> +	.owner = THIS_MODULE,
> +	.open = kvm_stat_data_open,
>  	.release = kvm_debugfs_release,
> -	.read    = simple_attr_read,
> -	.write   = simple_attr_write,
> -	.llseek  = no_llseek,
> -};
> -
> -static const struct file_operations *stat_fops_per_vm[] = {
> -	[KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
> -	[KVM_STAT_VM]   = &vm_stat_get_per_vm_fops,
> +	.read = simple_attr_read,
> +	.write = simple_attr_write,
> +	.llseek = no_llseek,
>  };
>  
>  static int vm_stat_get(void *_offset, u64 *val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  	u64 tmp_val;
>  
>  	*val = 0;
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> +		kvm_get_stat_per_vm(kvm, offset, &tmp_val);
>  		*val += tmp_val;
>  	}
>  	mutex_unlock(&kvm_lock);
> @@ -4142,15 +4149,13 @@ static int vm_stat_clear(void *_offset, u64 val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  
>  	if (val)
>  		return -EINVAL;
>  
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vm_stat_clear_per_vm((void *)&stat_tmp, 0);
> +		kvm_clear_stat_per_vm(kvm, offset);
>  	}
>  	mutex_unlock(&kvm_lock);
>  
> @@ -4163,14 +4168,12 @@ static int vcpu_stat_get(void *_offset, u64 *val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  	u64 tmp_val;
>  
>  	*val = 0;
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> +		kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
>  		*val += tmp_val;
>  	}
>  	mutex_unlock(&kvm_lock);
> @@ -4181,15 +4184,13 @@ static int vcpu_stat_clear(void *_offset, u64 val)
>  {
>  	unsigned offset = (long)_offset;
>  	struct kvm *kvm;
> -	struct kvm_stat_data stat_tmp = {.offset = offset};
>  
>  	if (val)
>  		return -EINVAL;
>  
>  	mutex_lock(&kvm_lock);
>  	list_for_each_entry(kvm, &vm_list, vm_list) {
> -		stat_tmp.kvm = kvm;
> -		vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
> +		kvm_clear_stat_per_vcpu(kvm, offset);
>  	}
>  	mutex_unlock(&kvm_lock);
>  
> @@ -4262,9 +4263,8 @@ static void kvm_init_debug(void)
>  
>  	kvm_debugfs_num_entries = 0;
>  	for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
> -		int mode = p->mode ? p->mode : 0644;
> -		debugfs_create_file(p->name, mode, kvm_debugfs_dir,
> -				    (void *)(long)p->offset,
> +		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> +				    kvm_debugfs_dir, (void *)(long)p->offset,
>  				    stat_fops[p->kind]);
>  	}
>  }
> 

Queued, thnaks.  Sorry for the delay.

Paolo

Patch
diff mbox series

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 7ed1e2f8641e..d3f2c0eae857 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1109,9 +1109,8 @@  enum kvm_stat_kind {
 };
 
 struct kvm_stat_data {
-	int offset;
-	int mode;
 	struct kvm *kvm;
+	struct kvm_stats_debugfs_item *dbgfs_item;
 };
 
 struct kvm_stats_debugfs_item {
@@ -1120,6 +1119,10 @@  struct kvm_stats_debugfs_item {
 	enum kvm_stat_kind kind;
 	int mode;
 };
+
+#define KVM_DBGFS_GET_MODE(dbgfs_item)                                         \
+	((dbgfs_item)->mode ? (dbgfs_item)->mode : 0644)
+
 extern struct kvm_stats_debugfs_item debugfs_entries[];
 extern struct dentry *kvm_debugfs_dir;
 
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 00268290dcbd..0ebd6aa95671 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -113,7 +113,7 @@  struct dentry *kvm_debugfs_dir;
 EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
 
 static int kvm_debugfs_num_entries;
-static const struct file_operations *stat_fops_per_vm[];
+static const struct file_operations stat_fops_per_vm;
 
 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
 			   unsigned long arg);
@@ -650,11 +650,11 @@  static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
 			return -ENOMEM;
 
 		stat_data->kvm = kvm;
-		stat_data->offset = p->offset;
-		stat_data->mode = p->mode ? p->mode : 0644;
+		stat_data->dbgfs_item = p;
 		kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
-		debugfs_create_file(p->name, stat_data->mode, kvm->debugfs_dentry,
-				    stat_data, stat_fops_per_vm[p->kind]);
+		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
+				    kvm->debugfs_dentry, stat_data,
+				    &stat_fops_per_vm);
 	}
 	return 0;
 }
@@ -4013,8 +4013,9 @@  static int kvm_debugfs_open(struct inode *inode, struct file *file,
 		return -ENOENT;
 
 	if (simple_attr_open(inode, file, get,
-			     stat_data->mode & S_IWUGO ? set : NULL,
-			     fmt)) {
+		    KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & 0222
+		    ? set : NULL,
+		    fmt)) {
 		kvm_put_kvm(stat_data->kvm);
 		return -ENOMEM;
 	}
@@ -4033,105 +4034,111 @@  static int kvm_debugfs_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static int vm_stat_get_per_vm(void *data, u64 *val)
+static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
 {
-	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
+	*val = *(ulong *)((void *)kvm + offset);
 
-	*val = *(ulong *)((void *)stat_data->kvm + stat_data->offset);
+	return 0;
+}
+
+static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
+{
+	*(ulong *)((void *)kvm + offset) = 0;
 
 	return 0;
 }
 
-static int vm_stat_clear_per_vm(void *data, u64 val)
+static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
 {
-	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
+	int i;
+	struct kvm_vcpu *vcpu;
 
-	if (val)
-		return -EINVAL;
+	*val = 0;
 
-	*(ulong *)((void *)stat_data->kvm + stat_data->offset) = 0;
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		*val += *(u64 *)((void *)vcpu + offset);
 
 	return 0;
 }
 
-static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
+static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
 {
-	__simple_attr_check_format("%llu\n", 0ull);
-	return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
-				vm_stat_clear_per_vm, "%llu\n");
-}
+	int i;
+	struct kvm_vcpu *vcpu;
 
-static const struct file_operations vm_stat_get_per_vm_fops = {
-	.owner   = THIS_MODULE,
-	.open    = vm_stat_get_per_vm_open,
-	.release = kvm_debugfs_release,
-	.read    = simple_attr_read,
-	.write   = simple_attr_write,
-	.llseek  = no_llseek,
-};
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		*(u64 *)((void *)vcpu + offset) = 0;
+
+	return 0;
+}
 
-static int vcpu_stat_get_per_vm(void *data, u64 *val)
+static int kvm_stat_data_get(void *data, u64 *val)
 {
-	int i;
+	int r = -EFAULT;
 	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
-	struct kvm_vcpu *vcpu;
-
-	*val = 0;
 
-	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
-		*val += *(u64 *)((void *)vcpu + stat_data->offset);
+	switch (stat_data->dbgfs_item->kind) {
+	case KVM_STAT_VM:
+		r = kvm_get_stat_per_vm(stat_data->kvm,
+					stat_data->dbgfs_item->offset, val);
+		break;
+	case KVM_STAT_VCPU:
+		r = kvm_get_stat_per_vcpu(stat_data->kvm,
+					  stat_data->dbgfs_item->offset, val);
+		break;
+	}
 
-	return 0;
+	return r;
 }
 
-static int vcpu_stat_clear_per_vm(void *data, u64 val)
+static int kvm_stat_data_clear(void *data, u64 val)
 {
-	int i;
+	int r = -EFAULT;
 	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
-	struct kvm_vcpu *vcpu;
 
 	if (val)
 		return -EINVAL;
 
-	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
-		*(u64 *)((void *)vcpu + stat_data->offset) = 0;
+	switch (stat_data->dbgfs_item->kind) {
+	case KVM_STAT_VM:
+		r = kvm_clear_stat_per_vm(stat_data->kvm,
+					  stat_data->dbgfs_item->offset);
+		break;
+	case KVM_STAT_VCPU:
+		r = kvm_clear_stat_per_vcpu(stat_data->kvm,
+					    stat_data->dbgfs_item->offset);
+		break;
+	}
 
-	return 0;
+	return r;
 }
 
-static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
+static int kvm_stat_data_open(struct inode *inode, struct file *file)
 {
 	__simple_attr_check_format("%llu\n", 0ull);
-	return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
-				 vcpu_stat_clear_per_vm, "%llu\n");
+	return kvm_debugfs_open(inode, file, kvm_stat_data_get,
+				kvm_stat_data_clear, "%llu\n");
 }
 
-static const struct file_operations vcpu_stat_get_per_vm_fops = {
-	.owner   = THIS_MODULE,
-	.open    = vcpu_stat_get_per_vm_open,
+static const struct file_operations stat_fops_per_vm = {
+	.owner = THIS_MODULE,
+	.open = kvm_stat_data_open,
 	.release = kvm_debugfs_release,
-	.read    = simple_attr_read,
-	.write   = simple_attr_write,
-	.llseek  = no_llseek,
-};
-
-static const struct file_operations *stat_fops_per_vm[] = {
-	[KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
-	[KVM_STAT_VM]   = &vm_stat_get_per_vm_fops,
+	.read = simple_attr_read,
+	.write = simple_attr_write,
+	.llseek = no_llseek,
 };
 
 static int vm_stat_get(void *_offset, u64 *val)
 {
 	unsigned offset = (long)_offset;
 	struct kvm *kvm;
-	struct kvm_stat_data stat_tmp = {.offset = offset};
 	u64 tmp_val;
 
 	*val = 0;
 	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
-		stat_tmp.kvm = kvm;
-		vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
+		kvm_get_stat_per_vm(kvm, offset, &tmp_val);
 		*val += tmp_val;
 	}
 	mutex_unlock(&kvm_lock);
@@ -4142,15 +4149,13 @@  static int vm_stat_clear(void *_offset, u64 val)
 {
 	unsigned offset = (long)_offset;
 	struct kvm *kvm;
-	struct kvm_stat_data stat_tmp = {.offset = offset};
 
 	if (val)
 		return -EINVAL;
 
 	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
-		stat_tmp.kvm = kvm;
-		vm_stat_clear_per_vm((void *)&stat_tmp, 0);
+		kvm_clear_stat_per_vm(kvm, offset);
 	}
 	mutex_unlock(&kvm_lock);
 
@@ -4163,14 +4168,12 @@  static int vcpu_stat_get(void *_offset, u64 *val)
 {
 	unsigned offset = (long)_offset;
 	struct kvm *kvm;
-	struct kvm_stat_data stat_tmp = {.offset = offset};
 	u64 tmp_val;
 
 	*val = 0;
 	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
-		stat_tmp.kvm = kvm;
-		vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
+		kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
 		*val += tmp_val;
 	}
 	mutex_unlock(&kvm_lock);
@@ -4181,15 +4184,13 @@  static int vcpu_stat_clear(void *_offset, u64 val)
 {
 	unsigned offset = (long)_offset;
 	struct kvm *kvm;
-	struct kvm_stat_data stat_tmp = {.offset = offset};
 
 	if (val)
 		return -EINVAL;
 
 	mutex_lock(&kvm_lock);
 	list_for_each_entry(kvm, &vm_list, vm_list) {
-		stat_tmp.kvm = kvm;
-		vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
+		kvm_clear_stat_per_vcpu(kvm, offset);
 	}
 	mutex_unlock(&kvm_lock);
 
@@ -4262,9 +4263,8 @@  static void kvm_init_debug(void)
 
 	kvm_debugfs_num_entries = 0;
 	for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
-		int mode = p->mode ? p->mode : 0644;
-		debugfs_create_file(p->name, mode, kvm_debugfs_dir,
-				    (void *)(long)p->offset,
+		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
+				    kvm_debugfs_dir, (void *)(long)p->offset,
 				    stat_fops[p->kind]);
 	}
 }