Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754827Ab3CEHFt (ORCPT ); Tue, 5 Mar 2013 02:05:49 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:44546 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753554Ab3CEHFq (ORCPT ); Tue, 5 Mar 2013 02:05:46 -0500 From: HATAYAMA Daisuke Subject: [PATCH v2 09/20] vmcore: clean up read_vmcore() To: vgoyal@redhat.com, ebiederm@xmission.com, cpw@sgi.com, kumagai-atsushi@mxc.nes.nec.co.jp, lisa.mitchell@hp.com, heiko.carstens@de.ibm.com, akpm@linux-foundation.org Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org Date: Sat, 02 Mar 2013 17:36:38 +0900 Message-ID: <20130302083638.31252.11496.stgit@localhost6.localdomain6> In-Reply-To: <20130302083447.31252.93914.stgit@localhost6.localdomain6> References: <20130302083447.31252.93914.stgit@localhost6.localdomain6> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 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: 3172 Lines: 115 Clean up read_vmcore(). Part for objects in vmcore_list can be written uniformly to part for ELF headers. By this change, duplicate and complicated codes are removed, so it's more clear to see what's done there. Also, by this change, map_offset_to_paddr() is no longer used. Remove it. Signed-off-by: HATAYAMA Daisuke --- fs/proc/vmcore.c | 68 ++++++++++++++++-------------------------------------- 1 files changed, 20 insertions(+), 48 deletions(-) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index e4751ce..09b7f34 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -118,27 +118,6 @@ static ssize_t read_from_oldmem(char *buf, size_t count, return read; } -/* Maps vmcore file offset to respective physical address in memroy. */ -static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list, - struct vmcore **m_ptr) -{ - struct vmcore *m; - u64 paddr; - - list_for_each_entry(m, vc_list, list) { - u64 start, end; - start = m->offset; - end = m->offset + m->size - 1; - if (offset >= start && offset <= end) { - paddr = m->paddr + offset - start; - *m_ptr = m; - return paddr; - } - } - *m_ptr = NULL; - return 0; -} - /* Read from the ELF header and then the crash dump. On error, negative value is * returned otherwise number of bytes read are returned. */ @@ -147,8 +126,8 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer, { ssize_t acc = 0, tmp; size_t tsz; - u64 start, nr_bytes; - struct vmcore *curr_m = NULL; + u64 start; + struct vmcore *m; if (buflen == 0 || *fpos >= vmcore_size) return 0; @@ -174,33 +153,26 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer, return acc; } - start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m); - if (!curr_m) - return -EINVAL; - - while (buflen) { - tsz = min_t(size_t, buflen, PAGE_SIZE - (start & ~PAGE_MASK)); - - /* Calculate left bytes in current memory segment. */ - nr_bytes = (curr_m->size - (start - curr_m->paddr)); - if (tsz > nr_bytes) - tsz = nr_bytes; - - tmp = read_from_oldmem(buffer, tsz, &start, 1); - if (tmp < 0) - return tmp; - buflen -= tsz; - *fpos += tsz; - buffer += tsz; - acc += tsz; - if (start >= (curr_m->paddr + curr_m->size)) { - if (curr_m->list.next == &vmcore_list) - return acc; /*EOF*/ - curr_m = list_entry(curr_m->list.next, - struct vmcore, list); - start = curr_m->paddr; + list_for_each_entry(m, &vmcore_list, list) { + if (*fpos < m->offset + m->size) { + tsz = m->offset + m->size - *fpos; + if (buflen < tsz) + tsz = buflen; + start = m->paddr + *fpos - m->offset; + tmp = read_from_oldmem(buffer, tsz, &start, 1); + if (tmp < 0) + return tmp; + buflen -= tsz; + *fpos += tsz; + buffer += tsz; + acc += tsz; + + /* leave now if filled buffer already */ + if (buflen == 0) + return acc; } } + return acc; } -- 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/