From: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
To: ebiederm@xmission.com, vgoyal@redhat.com, cpw@sgi.com,
kumagai-atsushi@mxc.nes.nec.co.jp, lisa.mitchell@hp.com
Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH 07/13] vmcore: modify read_vmcore() to read buffer on 2nd kernel
Date: Thu, 14 Feb 2013 19:12:21 +0900 [thread overview]
Message-ID: <20130214101221.22466.97636.stgit@localhost6.localdomain6> (raw)
In-Reply-To: <20130214100945.22466.4172.stgit@localhost6.localdomain6>
If a given vmcore object has VMCORE_2ND_KERNEL type, target data is in
the buffer on 2nd kernel.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
---
fs/proc/vmcore.c | 64 ++++++++++++++++++++++++++----------------------------
1 files changed, 31 insertions(+), 33 deletions(-)
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 77e0a0e..4125a65 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -146,8 +146,7 @@ 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;
+ struct vmcore *m;
if (buflen == 0 || *fpos >= vmcore_size)
return 0;
@@ -173,39 +172,38 @@ 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;
- if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
- tsz = buflen;
-
- /* Calculate left bytes in current memory segment. */
- nr_bytes = (curr_m->size - (start - curr_m->paddr));
- if (tsz > nr_bytes)
- tsz = nr_bytes;
-
- while (buflen) {
- 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;
+ switch (m->type) {
+ case VMCORE_OLD_MEMORY: {
+ u64 paddr = m->paddr + *fpos - m->offset;
+
+ tmp = read_from_oldmem(buffer, tsz, &paddr, 1);
+ if (tmp < 0)
+ return tmp;
+ break;
+ }
+ case VMCORE_2ND_KERNEL:
+ if (copy_to_user(buffer,
+ m->buf + (*fpos - m->offset),
+ tsz))
+ return -EFAULT;
+ break;
+ }
+ buflen -= tsz;
+ *fpos += tsz;
+ buffer += tsz;
+ acc += tsz;
+
+ /* leave now if filled buffer already */
+ if (buflen == 0)
+ return acc;
}
- if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
- tsz = buflen;
- /* Calculate left bytes in current memory segment. */
- nr_bytes = (curr_m->size - (start - curr_m->paddr));
- if (tsz > nr_bytes)
- tsz = nr_bytes;
}
+
return acc;
}
next prev parent reply other threads:[~2013-02-14 10:12 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-14 10:11 [PATCH 00/13] kdump, vmcore: support mmap() on /proc/vmcore HATAYAMA Daisuke
2013-02-14 10:11 ` [PATCH 01/13] vmcore: allocate buffer for ELF headers on page-size alignment HATAYAMA Daisuke
2013-02-15 15:01 ` Vivek Goyal
2013-02-14 10:11 ` [PATCH 02/13] vmcore: round up buffer size of ELF headers by PAGE_SIZE HATAYAMA Daisuke
2013-02-15 15:18 ` Vivek Goyal
2013-02-18 15:58 ` HATAYAMA Daisuke
2013-02-14 10:11 ` [PATCH 03/13] vmcore: fill unused part of buffer for ELF headers with 0 HATAYAMA Daisuke
2013-02-14 10:12 ` [PATCH 04/13] vmcore: introduce types for objects copied in 2nd kernel HATAYAMA Daisuke
2013-02-15 15:28 ` Vivek Goyal
2013-02-18 16:06 ` HATAYAMA Daisuke
2013-02-19 23:07 ` Vivek Goyal
2013-02-14 10:12 ` [PATCH 05/13] vmcore: modify ELF32 code according to new type HATAYAMA Daisuke
2013-02-15 15:30 ` Vivek Goyal
2013-02-18 16:11 ` HATAYAMA Daisuke
2013-02-14 10:12 ` [PATCH 06/13] vmcore: modify vmcore clean-up function to free buffer on 2nd kernel HATAYAMA Daisuke
2013-02-15 15:32 ` Vivek Goyal
2013-02-14 10:12 ` HATAYAMA Daisuke [this message]
2013-02-15 15:51 ` [PATCH 07/13] vmcore: modify read_vmcore() to read " Vivek Goyal
2013-02-14 10:12 ` [PATCH 08/13] vmcore: remove unused helper function HATAYAMA Daisuke
2013-02-15 15:52 ` Vivek Goyal
2013-02-14 10:12 ` [PATCH 09/13] vmcore: copy ELF note segments in buffer on 2nd kernel HATAYAMA Daisuke
2013-02-15 16:53 ` Vivek Goyal
2013-02-18 17:02 ` HATAYAMA Daisuke
2013-02-19 23:05 ` Vivek Goyal
2013-02-14 10:12 ` [PATCH 10/13] vmcore: round-up offset of vmcore object in page-size boundary HATAYAMA Daisuke
2013-02-14 10:12 ` [PATCH 11/13] vmcore: count holes generated by round-up operation for vmcore size HATAYAMA Daisuke
2013-02-14 10:12 ` [PATCH 12/13] vmcore: copy non page-size aligned head and tail pages in 2nd kernel HATAYAMA Daisuke
2013-02-14 10:12 ` [PATCH 13/13] vmcore: introduce mmap_vmcore() HATAYAMA Daisuke
2013-02-15 3:57 ` [PATCH 00/13] kdump, vmcore: support mmap() on /proc/vmcore Atsushi Kumagai
2013-02-18 0:16 ` Hatayama, Daisuke
2013-03-27 5:51 ` makedumpfile mmap() benchmark Jingbai Ma
2013-03-27 6:23 ` HATAYAMA Daisuke
2013-03-27 6:35 ` Jingbai Ma
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