The patch titled
Subject: vmcore: convert read_from_oldmem() to take an iov_iter
has been added to the -mm tree. Its filename is
vmcore-convert-read_from_oldmem-to-take-an-iov_iter.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/vmcore-convert-read_from_oldmem-to-take-an-iov_iter.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/vmcore-convert-read_from_oldmem-to-take-an-iov_iter.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: vmcore: convert read_from_oldmem() to take an iov_iter
Remove the read_from_oldmem() wrapper introduced earlier and convert all
the remaining callers to pass an iov_iter.
Link: https://lkml.kernel.org/r/20220408090636.560886-4-bhe@xxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
Cc: Amit Daniel Kachhap <amit.kachhap@xxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/crash_dump_64.c | 7 ++++-
fs/proc/vmcore.c | 40 +++++++++++-------------------
include/linux/crash_dump.h | 10 +++----
3 files changed, 25 insertions(+), 32 deletions(-)
--- a/arch/x86/kernel/crash_dump_64.c~vmcore-convert-read_from_oldmem-to-take-an-iov_iter
+++ a/arch/x86/kernel/crash_dump_64.c
@@ -54,6 +54,11 @@ ssize_t copy_oldmem_page_encrypted(struc
ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
{
- return read_from_oldmem(buf, count, ppos, 0,
+ struct kvec kvec = { .iov_base = buf, .iov_len = count };
+ struct iov_iter iter;
+
+ iov_iter_kvec(&iter, READ, &kvec, 1, count);
+
+ return read_from_oldmem(&iter, count, ppos,
cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT));
}
--- a/fs/proc/vmcore.c~vmcore-convert-read_from_oldmem-to-take-an-iov_iter
+++ a/fs/proc/vmcore.c
@@ -129,7 +129,7 @@ static int open_vmcore(struct inode *ino
}
/* Reads a page from the oldmem device from given offset. */
-static ssize_t read_from_oldmem_iter(struct iov_iter *iter, size_t count,
+ssize_t read_from_oldmem(struct iov_iter *iter, size_t count,
u64 *ppos, bool encrypted)
{
unsigned long pfn, offset;
@@ -178,27 +178,6 @@ static ssize_t read_from_oldmem_iter(str
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
*/
@@ -218,7 +197,12 @@ void __weak elfcorehdr_free(unsigned lon
*/
ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos)
{
- return read_from_oldmem(buf, count, ppos, 0, false);
+ struct kvec kvec = { .iov_base = buf, .iov_len = count };
+ struct iov_iter iter;
+
+ iov_iter_kvec(&iter, READ, &kvec, 1, count);
+
+ return read_from_oldmem(&iter, count, ppos, false);
}
/*
@@ -226,7 +210,13 @@ ssize_t __weak elfcorehdr_read(char *buf
*/
ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
{
- return read_from_oldmem(buf, count, ppos, 0, cc_platform_has(CC_ATTR_MEM_ENCRYPT));
+ struct kvec kvec = { .iov_base = buf, .iov_len = count };
+ struct iov_iter iter;
+
+ iov_iter_kvec(&iter, READ, &kvec, 1, count);
+
+ return read_from_oldmem(&iter, count, ppos,
+ cc_platform_has(CC_ATTR_MEM_ENCRYPT));
}
/*
@@ -402,7 +392,7 @@ static ssize_t __read_vmcore(struct iov_
m->offset + m->size - *fpos,
iov_iter_count(iter));
start = m->paddr + *fpos - m->offset;
- tmp = read_from_oldmem_iter(iter, tsz, &start,
+ tmp = read_from_oldmem(iter, tsz, &start,
cc_platform_has(CC_ATTR_MEM_ENCRYPT));
if (tmp < 0)
return tmp;
--- a/include/linux/crash_dump.h~vmcore-convert-read_from_oldmem-to-take-an-iov_iter
+++ a/include/linux/crash_dump.h
@@ -134,13 +134,11 @@ static inline int vmcore_add_device_dump
#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
#ifdef CONFIG_PROC_VMCORE
-ssize_t read_from_oldmem(char *buf, size_t count,
- u64 *ppos, int userbuf,
- bool encrypted);
+ssize_t read_from_oldmem(struct iov_iter *iter, size_t count,
+ u64 *ppos, bool encrypted);
#else
-static inline ssize_t read_from_oldmem(char *buf, size_t count,
- u64 *ppos, int userbuf,
- bool encrypted)
+static inline ssize_t read_from_oldmem(struct iov_iter *iter, size_t count,
+ u64 *ppos, bool encrypted)
{
return -EOPNOTSUPP;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
vmcore-convert-copy_oldmem_page-to-take-an-iov_iter.patch
vmcore-convert-__read_vmcore-to-use-an-iov_iter.patch
vmcore-convert-read_from_oldmem-to-take-an-iov_iter.patch
