Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757773Ab3EZGeq (ORCPT ); Sun, 26 May 2013 02:34:46 -0400 Received: from mail-pb0-f50.google.com ([209.85.160.50]:51305 "EHLO mail-pb0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755986Ab3EZGeo (ORCPT ); Sun, 26 May 2013 02:34:44 -0400 Message-ID: <51A1ACFB.3040600@gmail.com> Date: Sun, 26 May 2013 14:34:35 +0800 From: Zhang Yanfei User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.5) Gecko/20120607 Thunderbird/10.0.5 MIME-Version: 1.0 To: "Eric W. Biederman" , Vivek Goyal , Andrew Morton , "H. Peter Anvin" , Simon Horman CC: "linux-kernel@vger.kernel.org" , "kexec@lists.infradead.org" Subject: [PATCH v2 1/7] /dev/oldmem: Remove the interface References: <51A1AC4A.60506@gmail.com> In-Reply-To: <51A1AC4A.60506@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3303 Lines: 117 From: Zhang Yanfei /dev/oldmem provides the interface for us to access the "old memory" in the dump-capture kernel. Unfortunately, no one actually uses this interface. And this interface could actually cause some real problems if used on ia64 where the cached/uncached accesses are mixed. See the discussion from the link: https://lkml.org/lkml/2013/4/12/386. So Eric suggested that we should remove /dev/oldmem as an unused piece of code. Suggested-by: "Eric W. Biederman" Acked-by: "Eric W. Biederman" Signed-off-by: Zhang Yanfei Cc: Vivek Goyal Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Andrew Morton --- drivers/char/mem.c | 47 ----------------------------------------------- 1 files changed, 0 insertions(+), 47 deletions(-) diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 1ccbe94..bbe8ab4 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -21,7 +21,6 @@ #include #include #include -#include #include #include #include @@ -357,40 +356,6 @@ static int mmap_kmem(struct file *file, struct vm_area_struct *vma) } #endif -#ifdef CONFIG_CRASH_DUMP -/* - * Read memory corresponding to the old kernel. - */ -static ssize_t read_oldmem(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - unsigned long pfn, offset; - size_t read = 0, csize; - int rc = 0; - - while (count) { - pfn = *ppos / PAGE_SIZE; - if (pfn > saved_max_pfn) - return read; - - offset = (unsigned long)(*ppos % PAGE_SIZE); - if (count > PAGE_SIZE - offset) - csize = PAGE_SIZE - offset; - else - csize = count; - - rc = copy_oldmem_page(pfn, buf, csize, offset, 1); - if (rc < 0) - return rc; - buf += csize; - *ppos += csize; - read += csize; - count -= csize; - } - return read; -} -#endif - #ifdef CONFIG_DEVKMEM /* * This function reads the *virtual* memory as seen by the kernel. @@ -772,7 +737,6 @@ static int open_port(struct inode *inode, struct file *filp) #define aio_write_zero aio_write_null #define open_mem open_port #define open_kmem open_mem -#define open_oldmem open_mem static const struct file_operations mem_fops = { .llseek = memory_lseek, @@ -837,14 +801,6 @@ static const struct file_operations full_fops = { .write = write_full, }; -#ifdef CONFIG_CRASH_DUMP -static const struct file_operations oldmem_fops = { - .read = read_oldmem, - .open = open_oldmem, - .llseek = default_llseek, -}; -#endif - static const struct memdev { const char *name; umode_t mode; @@ -866,9 +822,6 @@ static const struct memdev { #ifdef CONFIG_PRINTK [11] = { "kmsg", 0644, &kmsg_fops, NULL }, #endif -#ifdef CONFIG_CRASH_DUMP - [12] = { "oldmem", 0, &oldmem_fops, NULL }, -#endif }; static int memory_open(struct inode *inode, struct file *filp) -- 1.7.1 -- 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/