2020-05-08 09:24:59

by Christoph Hellwig

Subject: [PATCH 10/11] fs: remove __vfs_read

Fold it into the two callers.

Signed-off-by: Christoph Hellwig <[email protected]>
---
fs/read_write.c | 43 +++++++++++++++++++++----------------------
include/linux/fs.h | 1 -
2 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/fs/read_write.c b/fs/read_write.c
index 0ffbed5fd8136..f0009b506014c 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -419,17 +419,6 @@ static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, lo
return ret;
}

-ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
- loff_t *pos)
-{
- if (file->f_op->read)
- return file->f_op->read(file, buf, count, pos);
- else if (file->f_op->read_iter)
- return new_sync_read(file, buf, count, pos);
- else
- return -EINVAL;
-}
-
ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
{
mm_segment_t old_fs = get_fs();
@@ -441,7 +430,12 @@ ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
if (count > MAX_RW_COUNT)
count = MAX_RW_COUNT;
set_fs(KERNEL_DS);
- ret = __vfs_read(file, (void __user *)buf, count, pos);
+ if (file->f_op->read)
+ ret = file->f_op->read(file, (void __user *)buf, count, pos);
+ else if (file->f_op->read_iter)
+ ret = new_sync_read(file, (void __user *)buf, count, pos);
+ else
+ ret = -EINVAL;
set_fs(old_fs);
if (ret > 0) {
fsnotify_access(file);
@@ -474,17 +468,22 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
return -EFAULT;

ret = rw_verify_area(READ, file, pos, count);
- if (!ret) {
- if (count > MAX_RW_COUNT)
- count = MAX_RW_COUNT;
- ret = __vfs_read(file, buf, count, pos);
- if (ret > 0) {
- fsnotify_access(file);
- add_rchar(current, ret);
- }
- inc_syscr(current);
- }
+ if (ret)
+ return ret;
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;

+ if (file->f_op->read)
+ ret = file->f_op->read(file, buf, count, pos);
+ else if (file->f_op->read_iter)
+ ret = new_sync_read(file, buf, count, pos);
+ else
+ ret = -EINVAL;
+ if (ret > 0) {
+ fsnotify_access(file);
+ add_rchar(current, ret);
+ }
+ inc_syscr(current);
return ret;
}

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 6441aaa25f8f2..4c10a07a36178 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1905,7 +1905,6 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
struct iovec *fast_pointer,
struct iovec **ret_pointer);

-extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
--
2.26.2

2020-05-08 15:47:56

by Ira Weiny

Subject: Re: [PATCH 10/11] fs: remove __vfs_read

On Fri, May 08, 2020 at 11:22:21AM +0200, Christoph Hellwig wrote:
> Fold it into the two callers.

In 5.7-rc4, it looks like __vfs_read() is called from
security/integrity/iint.c

Was that removed somewhere prior to this patch?

>
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
> fs/read_write.c | 43 +++++++++++++++++++++----------------------
> include/linux/fs.h | 1 -
> 2 files changed, 21 insertions(+), 23 deletions(-)
>
> diff --git a/fs/read_write.c b/fs/read_write.c
> index 0ffbed5fd8136..f0009b506014c 100644
> --- a/fs/read_write.c
> +++ b/fs/read_write.c
> @@ -419,17 +419,6 @@ static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, lo
> return ret;
> }
>
> -ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
> - loff_t *pos)
> -{
> - if (file->f_op->read)
> - return file->f_op->read(file, buf, count, pos);
> - else if (file->f_op->read_iter)
> - return new_sync_read(file, buf, count, pos);
> - else
> - return -EINVAL;
> -}
> -
> ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
> {
> mm_segment_t old_fs = get_fs();
> @@ -441,7 +430,12 @@ ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
> if (count > MAX_RW_COUNT)
> count = MAX_RW_COUNT;
> set_fs(KERNEL_DS);
> - ret = __vfs_read(file, (void __user *)buf, count, pos);
> + if (file->f_op->read)
> + ret = file->f_op->read(file, (void __user *)buf, count, pos);
> + else if (file->f_op->read_iter)
> + ret = new_sync_read(file, (void __user *)buf, count, pos);
> + else
> + ret = -EINVAL;
> set_fs(old_fs);
> if (ret > 0) {
> fsnotify_access(file);
> @@ -474,17 +468,22 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
> return -EFAULT;
>
> ret = rw_verify_area(READ, file, pos, count);
> - if (!ret) {
> - if (count > MAX_RW_COUNT)
> - count = MAX_RW_COUNT;
> - ret = __vfs_read(file, buf, count, pos);
> - if (ret > 0) {
> - fsnotify_access(file);
> - add_rchar(current, ret);
> - }
> - inc_syscr(current);
> - }
> + if (ret)
> + return ret;
> + if (count > MAX_RW_COUNT)
> + count = MAX_RW_COUNT;

Couldn't this clean up still happen while keeping __vfs_read()?

Ira

> + if (file->f_op->read)
> + ret = file->f_op->read(file, buf, count, pos);
> + else if (file->f_op->read_iter)
> + ret = new_sync_read(file, buf, count, pos);
> + else
> + ret = -EINVAL;
> + if (ret > 0) {
> + fsnotify_access(file);
> + add_rchar(current, ret);
> + }
> + inc_syscr(current);
> return ret;
> }
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 6441aaa25f8f2..4c10a07a36178 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1905,7 +1905,6 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
> struct iovec *fast_pointer,
> struct iovec **ret_pointer);
>
> -extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
> extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
> extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
> extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
> --
> 2.26.2
>

2020-05-08 15:48:46

by Christoph Hellwig

Subject: Re: [PATCH 10/11] fs: remove __vfs_read

On Fri, May 08, 2020 at 08:45:53AM -0700, Ira Weiny wrote:
> On Fri, May 08, 2020 at 11:22:21AM +0200, Christoph Hellwig wrote:
> > Fold it into the two callers.
>
> In 5.7-rc4, it looks like __vfs_read() is called from
> security/integrity/iint.c
>
> Was that removed somewhere prior to this patch?

[PATCH 08/11] integrity/ima: switch to using __kernel_read