All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Al Viro <viro@zeniv.linux.org.uk>,
	Michael Ellerman <mpe@ellerman.id.au>,
	x86@kernel.org
Cc: Kees Cook <keescook@chromium.org>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 01/11] mem: remove duplicate ops for /dev/zero and /dev/null
Date: Mon, 17 Aug 2020 09:32:02 +0200	[thread overview]
Message-ID: <20200817073212.830069-2-hch@lst.de> (raw)
In-Reply-To: <20200817073212.830069-1-hch@lst.de>

There is no good reason to implement both the traditional ->read and
->write as well as the iter based ops.  So implement just the iter
based ones.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/char/mem.c | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 687d4af6945d36..14851f36787372 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -670,18 +670,6 @@ static ssize_t write_port(struct file *file, const char __user *buf,
 	return tmp-buf;
 }
 
-static ssize_t read_null(struct file *file, char __user *buf,
-			 size_t count, loff_t *ppos)
-{
-	return 0;
-}
-
-static ssize_t write_null(struct file *file, const char __user *buf,
-			  size_t count, loff_t *ppos)
-{
-	return count;
-}
-
 static ssize_t read_iter_null(struct kiocb *iocb, struct iov_iter *to)
 {
 	return 0;
@@ -872,7 +860,6 @@ static int open_port(struct inode *inode, struct file *filp)
 
 #define zero_lseek	null_lseek
 #define full_lseek      null_lseek
-#define write_zero	write_null
 #define write_iter_zero	write_iter_null
 #define open_mem	open_port
 #define open_kmem	open_mem
@@ -903,8 +890,6 @@ static const struct file_operations __maybe_unused kmem_fops = {
 
 static const struct file_operations null_fops = {
 	.llseek		= null_lseek,
-	.read		= read_null,
-	.write		= write_null,
 	.read_iter	= read_iter_null,
 	.write_iter	= write_iter_null,
 	.splice_write	= splice_write_null,
@@ -919,7 +904,6 @@ static const struct file_operations __maybe_unused port_fops = {
 
 static const struct file_operations zero_fops = {
 	.llseek		= zero_lseek,
-	.write		= write_zero,
 	.read_iter	= read_iter_zero,
 	.write_iter	= write_iter_zero,
 	.mmap		= mmap_zero,
-- 
2.28.0


WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de>
To: Al Viro <viro@zeniv.linux.org.uk>,
	Michael Ellerman <mpe@ellerman.id.au>,
	x86@kernel.org
Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org, Kees Cook <keescook@chromium.org>,
	linux-kernel@vger.kernel.org
Subject: [PATCH 01/11] mem: remove duplicate ops for /dev/zero and /dev/null
Date: Mon, 17 Aug 2020 09:32:02 +0200	[thread overview]
Message-ID: <20200817073212.830069-2-hch@lst.de> (raw)
In-Reply-To: <20200817073212.830069-1-hch@lst.de>

There is no good reason to implement both the traditional ->read and
->write as well as the iter based ops.  So implement just the iter
based ones.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/char/mem.c | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 687d4af6945d36..14851f36787372 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -670,18 +670,6 @@ static ssize_t write_port(struct file *file, const char __user *buf,
 	return tmp-buf;
 }
 
-static ssize_t read_null(struct file *file, char __user *buf,
-			 size_t count, loff_t *ppos)
-{
-	return 0;
-}
-
-static ssize_t write_null(struct file *file, const char __user *buf,
-			  size_t count, loff_t *ppos)
-{
-	return count;
-}
-
 static ssize_t read_iter_null(struct kiocb *iocb, struct iov_iter *to)
 {
 	return 0;
@@ -872,7 +860,6 @@ static int open_port(struct inode *inode, struct file *filp)
 
 #define zero_lseek	null_lseek
 #define full_lseek      null_lseek
-#define write_zero	write_null
 #define write_iter_zero	write_iter_null
 #define open_mem	open_port
 #define open_kmem	open_mem
@@ -903,8 +890,6 @@ static const struct file_operations __maybe_unused kmem_fops = {
 
 static const struct file_operations null_fops = {
 	.llseek		= null_lseek,
-	.read		= read_null,
-	.write		= write_null,
 	.read_iter	= read_iter_null,
 	.write_iter	= write_iter_null,
 	.splice_write	= splice_write_null,
@@ -919,7 +904,6 @@ static const struct file_operations __maybe_unused port_fops = {
 
 static const struct file_operations zero_fops = {
 	.llseek		= zero_lseek,
-	.write		= write_zero,
 	.read_iter	= read_iter_zero,
 	.write_iter	= write_iter_zero,
 	.mmap		= mmap_zero,
-- 
2.28.0


  reply	other threads:[~2020-08-17  7:32 UTC|newest]

Thread overview: 74+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-17  7:32 remove the last set_fs() in common code, and remove it for x86 and powerpc Christoph Hellwig
2020-08-17  7:32 ` Christoph Hellwig
2020-08-17  7:32 ` Christoph Hellwig [this message]
2020-08-17  7:32   ` [PATCH 01/11] mem: remove duplicate ops for /dev/zero and /dev/null Christoph Hellwig
2020-08-18 19:33   ` Kees Cook
2020-08-18 19:33     ` Kees Cook
2020-08-17  7:32 ` [PATCH 02/11] fs: don't allow kernel reads and writes without iter ops Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-18 19:34   ` Kees Cook
2020-08-18 19:34     ` Kees Cook
2020-08-17  7:32 ` [PATCH 03/11] fs: don't allow splice read/write without explicit ops Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-18 19:39   ` Kees Cook
2020-08-18 19:39     ` Kees Cook
2020-08-18 19:54     ` Christoph Hellwig
2020-08-18 19:54       ` Christoph Hellwig
2020-08-18 19:58       ` Kees Cook
2020-08-18 19:58         ` Kees Cook
2020-08-18 20:07         ` Christoph Hellwig
2020-08-18 20:07           ` Christoph Hellwig
2020-08-17  7:32 ` [PATCH 04/11] uaccess: add infrastructure for kernel builds with set_fs() Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-18 19:40   ` Kees Cook
2020-08-18 19:40     ` Kees Cook
2020-08-17  7:32 ` [PATCH 05/11] test_bitmap: skip user bitmap tests for !CONFIG_SET_FS Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-17  7:50   ` Christophe Leroy
2020-08-17  7:52     ` Christoph Hellwig
2020-08-17  7:52       ` Christoph Hellwig
2020-08-18 19:43   ` Kees Cook
2020-08-18 19:43     ` Kees Cook
2020-08-17  7:32 ` [PATCH 06/11] lkdtm: disable set_fs-based " Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-18 19:32   ` Kees Cook
2020-08-18 19:32     ` Kees Cook
2020-08-17  7:32 ` [PATCH 07/11] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h Christoph Hellwig
2020-08-17  7:32   ` [PATCH 07/11] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32, 64}_types.h Christoph Hellwig
2020-08-18 19:27   ` [PATCH 07/11] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h Kees Cook
2020-08-18 19:27     ` Kees Cook
2020-08-17  7:32 ` [PATCH 08/11] x86: make TASK_SIZE_MAX usable from assembly code Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-18 19:44   ` Kees Cook
2020-08-18 19:44     ` Kees Cook
2020-08-18 19:55     ` Christoph Hellwig
2020-08-18 19:55       ` Christoph Hellwig
2020-08-18 19:59       ` Kees Cook
2020-08-18 19:59         ` Kees Cook
2020-08-18 20:00         ` Christoph Hellwig
2020-08-18 20:00           ` Christoph Hellwig
2020-08-18 20:08           ` Kees Cook
2020-08-18 20:08             ` Kees Cook
2020-08-17  7:32 ` [PATCH 09/11] x86: remove address space overrides using set_fs() Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-17  8:23   ` David Laight
2020-08-17  8:23     ` David Laight
2020-08-27  9:37     ` 'Christoph Hellwig'
2020-08-27  9:37       ` 'Christoph Hellwig'
2020-08-18 19:46   ` Kees Cook
2020-08-18 19:46     ` Kees Cook
2020-08-17  7:32 ` [PATCH 10/11] powerpc: use non-set_fs based maccess routines Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-17 15:47   ` Christophe Leroy
2020-08-17  7:32 ` [PATCH 11/11] powerpc: remove address space overrides using set_fs() Christoph Hellwig
2020-08-17  7:32   ` Christoph Hellwig
2020-08-17  7:39 ` remove the last set_fs() in common code, and remove it for x86 and powerpc Christoph Hellwig
2020-08-17  7:39   ` Christoph Hellwig
2020-08-18 17:46 ` Christophe Leroy
2020-08-18 18:05   ` Christoph Hellwig
2020-08-18 18:05     ` Christoph Hellwig
2020-08-18 18:23     ` Christophe Leroy
2020-08-18 18:23       ` Christophe Leroy
2020-08-19  7:16       ` Christophe Leroy
2020-08-19  7:22         ` iter and normal ops on /dev/zero & co, was " Christoph Hellwig
2020-08-19  7:22           ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200817073212.830069-2-hch@lst.de \
    --to=hch@lst.de \
    --cc=keescook@chromium.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=viro@zeniv.linux.org.uk \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.