[PATCH 5.18 112/181] vmcore: convert copy_oldmem_page() to take an iov_iter
From: Greg Kroah-Hartman
Date: Mon Jun 27 2022 - 07:56:50 EST
From: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
[ Upstream commit 5d8de293c224896a4da99763fce4f9794308caf4 ]
Patch series "Convert vmcore to use an iov_iter", v5.
For some reason several people have been sending bad patches to fix
compiler warnings in vmcore recently. Here's how it should be done.
Compile-tested only on x86. As noted in the first patch, s390 should take
this conversion a bit further, but I'm not inclined to do that work
myself.
This patch (of 3):
Instead of passing in a 'buf' and 'userbuf' argument, pass in an iov_iter.
s390 needs more work to pass the iov_iter down further, or refactor, but
I'd be more comfortable if someone who can test on s390 did that work.
It's more convenient to convert the whole of read_from_oldmem() to take an
iov_iter at the same time, so rename it to read_from_oldmem_iter() and add
a temporary read_from_oldmem() wrapper that creates an iov_iter.
Link: https://lkml.kernel.org/r/20220408090636.560886-1-bhe@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20220408090636.560886-2-bhe@xxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm/kernel/crash_dump.c | 27 +++-------------
arch/arm64/kernel/crash_dump.c | 29 +++--------------
arch/ia64/kernel/crash_dump.c | 32 +++----------------
arch/mips/kernel/crash_dump.c | 27 +++-------------
arch/powerpc/kernel/crash_dump.c | 35 +++------------------
arch/riscv/kernel/crash_dump.c | 26 +++------------
arch/s390/kernel/crash_dump.c | 13 +++++---
arch/sh/kernel/crash_dump.c | 29 +++--------------
arch/x86/kernel/crash_dump_32.c | 29 +++--------------
arch/x86/kernel/crash_dump_64.c | 41 +++++++-----------------
fs/proc/vmcore.c | 54 ++++++++++++++++++++------------
include/linux/crash_dump.h | 9 +++---
12 files changed, 91 insertions(+), 260 deletions(-)
diff --git a/arch/arm/kernel/crash_dump.c b/arch/arm/kernel/crash_dump.c
index 53cb92435392..938bd932df9a 100644
--- a/arch/arm/kernel/crash_dump.c
+++ b/arch/arm/kernel/crash_dump.c
@@ -14,22 +14,10 @@
#include <linux/crash_dump.h>
#include <linux/uaccess.h>
#include <linux/io.h>
+#include <linux/uio.h>
-/**
- * copy_oldmem_page() - copy one page from old kernel memory
- * @pfn: page frame number to be copied
- * @buf: buffer where the copied page is placed
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page
- * @userbuf: if set, @buf is int he user address space
- *
- * This function copies one page from old kernel memory into buffer pointed by
- * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes
- * copied or negative error in case of failure.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset,
- int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
@@ -40,14 +28,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
if (!vaddr)
return -ENOMEM;
- if (userbuf) {
- if (copy_to_user(buf, vaddr + offset, csize)) {
- iounmap(vaddr);
- return -EFAULT;
- }
- } else {
- memcpy(buf, vaddr + offset, csize);
- }
+ csize = copy_to_iter(vaddr + offset, csize, iter);
iounmap(vaddr);
return csize;
diff --git a/arch/arm64/kernel/crash_dump.c b/arch/arm64/kernel/crash_dump.c
index 58303a9ec32c..670e4ce81822 100644
--- a/arch/arm64/kernel/crash_dump.c
+++ b/arch/arm64/kernel/crash_dump.c
@@ -9,25 +9,11 @@
#include <linux/crash_dump.h>
#include <linux/errno.h>
#include <linux/io.h>
-#include <linux/memblock.h>
-#include <linux/uaccess.h>
+#include <linux/uio.h>
#include <asm/memory.h>
-/**
- * copy_oldmem_page() - copy one page from old kernel memory
- * @pfn: page frame number to be copied
- * @buf: buffer where the copied page is placed
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page
- * @userbuf: if set, @buf is in a user address space
- *
- * This function copies one page from old kernel memory into buffer pointed by
- * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes
- * copied or negative error in case of failure.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset,
- int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
@@ -38,14 +24,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
if (!vaddr)
return -ENOMEM;
- if (userbuf) {
- if (copy_to_user((char __user *)buf, vaddr + offset, csize)) {
- memunmap(vaddr);
- return -EFAULT;
- }
- } else {
- memcpy(buf, vaddr + offset, csize);
- }
+ csize = copy_to_iter(vaddr + offset, csize, iter);
memunmap(vaddr);
diff --git a/arch/ia64/kernel/crash_dump.c b/arch/ia64/kernel/crash_dump.c
index 0ed3c3dee4cd..4ef68e2aa757 100644
--- a/arch/ia64/kernel/crash_dump.c
+++ b/arch/ia64/kernel/crash_dump.c
@@ -10,42 +10,18 @@
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/crash_dump.h>
-
+#include <linux/uio.h>
#include <asm/page.h>
-#include <linux/uaccess.h>
-/**
- * copy_oldmem_page - copy one page from "oldmem"
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
- */
-ssize_t
-copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
if (!csize)
return 0;
vaddr = __va(pfn<<PAGE_SHIFT);
- if (userbuf) {
- if (copy_to_user(buf, (vaddr + offset), csize)) {
- return -EFAULT;
- }
- } else
- memcpy(buf, (vaddr + offset), csize);
+ csize = copy_to_iter(vaddr + offset, csize, iter);
return csize;
}
diff --git a/arch/mips/kernel/crash_dump.c b/arch/mips/kernel/crash_dump.c
index 2e50f55185a6..6e50f4902409 100644
--- a/arch/mips/kernel/crash_dump.c
+++ b/arch/mips/kernel/crash_dump.c
@@ -1,22 +1,10 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/highmem.h>
#include <linux/crash_dump.h>
+#include <linux/uio.h>
-/**
- * copy_oldmem_page - copy one page from "oldmem"
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
@@ -24,14 +12,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
return 0;
vaddr = kmap_local_pfn(pfn);
-
- if (!userbuf) {
- memcpy(buf, vaddr + offset, csize);
- } else {
- if (copy_to_user(buf, vaddr + offset, csize))
- csize = -EFAULT;
- }
-
+ csize = copy_to_iter(vaddr + offset, csize, iter);
kunmap_local(vaddr);
return csize;
diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c
index 5693e1c67c2b..32b4a97f1b79 100644
--- a/arch/powerpc/kernel/crash_dump.c
+++ b/arch/powerpc/kernel/crash_dump.c
@@ -16,7 +16,7 @@
#include <asm/kdump.h>
#include <asm/prom.h>
#include <asm/firmware.h>
-#include <linux/uaccess.h>
+#include <linux/uio.h>
#include <asm/rtas.h>
#include <asm/inst.h>
@@ -68,33 +68,8 @@ void __init setup_kdump_trampoline(void)
}
#endif /* CONFIG_NONSTATIC_KERNEL */
-static size_t copy_oldmem_vaddr(void *vaddr, char *buf, size_t csize,
- unsigned long offset, int userbuf)
-{
- if (userbuf) {
- if (copy_to_user((char __user *)buf, (vaddr + offset), csize))
- return -EFAULT;
- } else
- memcpy(buf, (vaddr + offset), csize);
-
- return csize;
-}
-
-/**
- * copy_oldmem_page - copy one page from "oldmem"
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
phys_addr_t paddr;
@@ -107,10 +82,10 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
if (memblock_is_region_memory(paddr, csize)) {
vaddr = __va(paddr);
- csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf);
+ csize = copy_to_iter(vaddr + offset, csize, iter);
} else {
vaddr = ioremap_cache(paddr, PAGE_SIZE);
- csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf);
+ csize = copy_to_iter(vaddr + offset, csize, iter);
iounmap(vaddr);
}
diff --git a/arch/riscv/kernel/crash_dump.c b/arch/riscv/kernel/crash_dump.c
index 86cc0ada5752..ea2158cee97b 100644
--- a/arch/riscv/kernel/crash_dump.c
+++ b/arch/riscv/kernel/crash_dump.c
@@ -7,22 +7,10 @@
#include <linux/crash_dump.h>
#include <linux/io.h>
+#include <linux/uio.h>
-/**
- * copy_oldmem_page() - copy one page from old kernel memory
- * @pfn: page frame number to be copied
- * @buf: buffer where the copied page is placed
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page
- * @userbuf: if set, @buf is in a user address space
- *
- * This function copies one page from old kernel memory into buffer pointed by
- * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes
- * copied or negative error in case of failure.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset,
- int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void *vaddr;
@@ -33,13 +21,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
if (!vaddr)
return -ENOMEM;
- if (userbuf) {
- if (copy_to_user((char __user *)buf, vaddr + offset, csize)) {
- memunmap(vaddr);
- return -EFAULT;
- }
- } else
- memcpy(buf, vaddr + offset, csize);
+ csize = copy_to_iter(vaddr + offset, csize, iter);
memunmap(vaddr);
return csize;
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index 69819b765250..a2c1c55daec0 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/memblock.h>
#include <linux/elf.h>
+#include <linux/uio.h>
#include <asm/asm-offsets.h>
#include <asm/os_info.h>
#include <asm/elf.h>
@@ -212,8 +213,8 @@ static int copy_oldmem_user(void __user *dst, unsigned long src, size_t count)
/*
* Copy one page from "oldmem"
*/
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
+ unsigned long offset)
{
unsigned long src;
int rc;
@@ -221,10 +222,12 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
if (!csize)
return 0;
src = pfn_to_phys(pfn) + offset;
- if (userbuf)
- rc = copy_oldmem_user((void __force __user *) buf, src, csize);
+
+ /* XXX: pass the iov_iter down to a common function */
+ if (iter_is_iovec(iter))
+ rc = copy_oldmem_user(iter->iov->iov_base, src, csize);
else
- rc = copy_oldmem_kernel((void *) buf, src, csize);
+ rc = copy_oldmem_kernel(iter->kvec->iov_base, src, csize);
return rc;
}
diff --git a/arch/sh/kernel/crash_dump.c b/arch/sh/kernel/crash_dump.c
index 5b41b59698c1..19ce6a950aac 100644
--- a/arch/sh/kernel/crash_dump.c
+++ b/arch/sh/kernel/crash_dump.c
@@ -8,23 +8,11 @@
#include <linux/errno.h>
#include <linux/crash_dump.h>
#include <linux/io.h>
+#include <linux/uio.h>
#include <linux/uaccess.h>
-/**
- * copy_oldmem_page - copy one page from "oldmem"
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
void __iomem *vaddr;
@@ -32,15 +20,8 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
return 0;
vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
-
- if (userbuf) {
- if (copy_to_user((void __user *)buf, (vaddr + offset), csize)) {
- iounmap(vaddr);
- return -EFAULT;
- }
- } else
- memcpy(buf, (vaddr + offset), csize);
-
+ csize = copy_to_iter(vaddr + offset, csize, iter);
iounmap(vaddr);
+
return csize;
}
diff --git a/arch/x86/kernel/crash_dump_32.c b/arch/x86/kernel/crash_dump_32.c
index 5fcac46aaf6b..5f4ae5476e19 100644
--- a/arch/x86/kernel/crash_dump_32.c
+++ b/arch/x86/kernel/crash_dump_32.c
@@ -10,8 +10,7 @@
#include <linux/errno.h>
#include <linux/highmem.h>
#include <linux/crash_dump.h>
-
-#include <linux/uaccess.h>
+#include <linux/uio.h>
static inline bool is_crashed_pfn_valid(unsigned long pfn)
{
@@ -29,21 +28,8 @@ static inline bool is_crashed_pfn_valid(unsigned long pfn)
#endif
}
-/**
- * copy_oldmem_page - copy one page from "oldmem"
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from "oldmem". For this page, there might be no pte mapped
- * in the current kernel.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
+ unsigned long offset)
{
void *vaddr;
@@ -54,14 +40,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
return -EFAULT;
vaddr = kmap_local_pfn(pfn);
-
- if (!userbuf) {
- memcpy(buf, vaddr + offset, csize);
- } else {
- if (copy_to_user(buf, vaddr + offset, csize))
- csize = -EFAULT;
- }
-
+ csize = copy_to_iter(vaddr + offset, csize, iter);
kunmap_local(vaddr);
return csize;
diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 97529552dd24..94fe4aff9694 100644
--- a/arch/x86/kernel/crash_dump_64.c
+++ b/arch/x86/kernel/crash_dump_64.c
@@ -8,12 +8,12 @@
#include <linux/errno.h>
#include <linux/crash_dump.h>
-#include <linux/uaccess.h>
+#include <linux/uio.h>
#include <linux/io.h>
#include <linux/cc_platform.h>
-static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf,
+static ssize_t __copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset,
bool encrypted)
{
void *vaddr;
@@ -29,46 +29,27 @@ static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
if (!vaddr)
return -ENOMEM;
- if (userbuf) {
- if (copy_to_user((void __user *)buf, vaddr + offset, csize)) {
- iounmap((void __iomem *)vaddr);
- return -EFAULT;
- }
- } else
- memcpy(buf, vaddr + offset, csize);
+ csize = copy_to_iter(vaddr + offset, csize, iter);
iounmap((void __iomem *)vaddr);
return csize;
}
-/**
- * copy_oldmem_page - copy one page of memory
- * @pfn: page frame number to be copied
- * @buf: target memory address for the copy; this can be in kernel address
- * space or user address space (see @userbuf)
- * @csize: number of bytes to copy
- * @offset: offset in bytes into the page (based on pfn) to begin the copy
- * @userbuf: if set, @buf is in user address space, use copy_to_user(),
- * otherwise @buf is in kernel address space, use memcpy().
- *
- * Copy a page from the old kernel's memory. For this page, there is no pte
- * mapped in the current kernel. We stitch up a pte, similar to kmap_atomic.
- */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
+ unsigned long offset)
{
- return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, false);
+ return __copy_oldmem_page(iter, pfn, csize, offset, false);
}
-/**
+/*
* copy_oldmem_page_encrypted - same as copy_oldmem_page() above but ioremap the
* memory with the encryption mask set to accommodate kdump on SME-enabled
* machines.
*/
-ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page_encrypted(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset)
{
- return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, true);
+ return __copy_oldmem_page(iter, pfn, csize, offset, true);
}
ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 6f1b8ddc6f7a..54dda2e19ed1 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -26,6 +26,7 @@
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <linux/uaccess.h>
+#include <linux/uio.h>
#include <linux/cc_platform.h>
#include <asm/io.h>
#include "internal.h"
@@ -128,9 +129,8 @@ static int open_vmcore(struct inode *inode, struct file *file)
}
/* Reads a page from the oldmem device from given offset. */
-ssize_t read_from_oldmem(char *buf, size_t count,
- u64 *ppos, int userbuf,
- bool encrypted)
+static ssize_t read_from_oldmem_iter(struct iov_iter *iter, size_t count,
+ u64 *ppos, bool encrypted)
{
unsigned long pfn, offset;
size_t nr_bytes;
@@ -152,29 +152,23 @@ ssize_t read_from_oldmem(char *buf, size_t count,
/* If pfn is not ram, return zeros for sparse dump files */
if (!pfn_is_ram(pfn)) {
- tmp = 0;
- if (!userbuf)
- memset(buf, 0, nr_bytes);
- else if (clear_user(buf, nr_bytes))
- tmp = -EFAULT;
+ tmp = iov_iter_zero(nr_bytes, iter);
} else {
if (encrypted)
- tmp = copy_oldmem_page_encrypted(pfn, buf,
+ tmp = copy_oldmem_page_encrypted(iter, pfn,
nr_bytes,
- offset,
- userbuf);
+ offset);
else
- tmp = copy_oldmem_page(pfn, buf, nr_bytes,
- offset, userbuf);
+ tmp = copy_oldmem_page(iter, pfn, nr_bytes,
+ offset);
}
- if (tmp < 0) {
+ if (tmp < nr_bytes) {
srcu_read_unlock(&vmcore_cb_srcu, idx);
- return tmp;
+ return -EFAULT;
}
*ppos += nr_bytes;
count -= nr_bytes;
- buf += nr_bytes;
read += nr_bytes;
++pfn;
offset = 0;
@@ -184,6 +178,27 @@ ssize_t read_from_oldmem(char *buf, size_t count,
return read;
}
+ssize_t read_from_oldmem(char *buf, size_t count,
+ u64 *ppos, int userbuf,
+ bool encrypted)
+{
+ struct iov_iter iter;
+ struct iovec iov;
+ struct kvec kvec;
+
+ if (userbuf) {
+ iov.iov_base = (__force void __user *)buf;
+ iov.iov_len = count;
+ iov_iter_init(&iter, READ, &iov, 1, count);
+ } else {
+ kvec.iov_base = buf;
+ kvec.iov_len = count;
+ iov_iter_kvec(&iter, READ, &kvec, 1, count);
+ }
+
+ return read_from_oldmem_iter(&iter, count, ppos, encrypted);
+}
+
/*
* Architectures may override this function to allocate ELF header in 2nd kernel
*/
@@ -228,11 +243,10 @@ int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma,
/*
* Architectures which support memory encryption override this.
*/
-ssize_t __weak
-copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize,
- unsigned long offset, int userbuf)
+ssize_t __weak copy_oldmem_page_encrypted(struct iov_iter *iter,
+ unsigned long pfn, size_t csize, unsigned long offset)
{
- return copy_oldmem_page(pfn, buf, csize, offset, userbuf);
+ return copy_oldmem_page(iter, pfn, csize, offset);
}
/*
diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h
index 620821549b23..a1cf7d5c03c7 100644
--- a/include/linux/crash_dump.h
+++ b/include/linux/crash_dump.h
@@ -24,11 +24,10 @@ extern int remap_oldmem_pfn_range(struct vm_area_struct *vma,
unsigned long from, unsigned long pfn,
unsigned long size, pgprot_t prot);
-extern ssize_t copy_oldmem_page(unsigned long, char *, size_t,
- unsigned long, int);
-extern ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf,
- size_t csize, unsigned long offset,
- int userbuf);
+ssize_t copy_oldmem_page(struct iov_iter *i, unsigned long pfn, size_t csize,
+ unsigned long offset);
+ssize_t copy_oldmem_page_encrypted(struct iov_iter *iter, unsigned long pfn,
+ size_t csize, unsigned long offset);
void vmcore_cleanup(void);
--
2.35.1