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s390: Allow vmalloc target buffers for copy_from_oldmem()

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Currently copy_from_oldmem() is not able to copy to virtual memory.
When using kexec pre-allocated ELF header, copy_from_oldmem()
is used to copy the ELF notes information to vmalloc buffers.

So fix this and use the new function copy_from_realmem() that allows
copying also to vmalloc memory.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Michael Holzheu 2013-09-27 15:41:43 +02:00 committed by Martin Schwidefsky
parent 22bfda6688
commit 4d3b0664a0
1 changed files with 20 additions and 22 deletions
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42
arch/s390/kernel/crash_dump.c
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@ -40,28 +40,26 @@ static inline void *load_real_addr(void *addr)
}
/*
* Copy up to one page to vmalloc or real memory
* Copy real to virtual or real memory
*/
static ssize_t copy_page_real(void *buf, void *src, size_t csize)
static int copy_from_realmem(void *dest, void *src, size_t count)
{
size_t size;
unsigned long size;
int rc;
if (is_vmalloc_addr(buf)) {
BUG_ON(csize >= PAGE_SIZE);
/* If buf is not page aligned, copy first part */
size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize);
if (size) {
if (memcpy_real(load_real_addr(buf), src, size))
return -EFAULT;
buf += size;
src += size;
}
/* Copy second part */
size = csize - size;
return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0;
} else {
return memcpy_real(buf, src, csize);
}
if (!count)
return 0;
if (!is_vmalloc_or_module_addr(dest))
return memcpy_real(dest, src, count);
do {
size = min(count, PAGE_SIZE - (__pa(dest) & ~PAGE_MASK));
if (memcpy_real(load_real_addr(dest), src, size))
return -EFAULT;
count -= size;
dest += size;
src += size;
} while (count);
return 0;
}
/*
@ -114,7 +112,7 @@ static ssize_t copy_oldmem_page_kdump(char *buf, size_t csize,
rc = copy_to_user_real((void __force __user *) buf,
(void *) src, csize);
else
rc = copy_page_real(buf, (void *) src, csize);
rc = copy_from_realmem(buf, (void *) src, csize);
return (rc == 0) ? rc : csize;
}
@ -210,7 +208,7 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
if (OLDMEM_BASE) {
if ((unsigned long) src < OLDMEM_SIZE) {
copied = min(count, OLDMEM_SIZE - (unsigned long) src);
rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
rc = copy_from_realmem(dest, src + OLDMEM_BASE, copied);
if (rc)
return rc;
}
@ -223,7 +221,7 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
return rc;
}
}
return memcpy_real(dest + copied, src + copied, count - copied);
return copy_from_realmem(dest + copied, src + copied, count - copied);
}
/*