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author | 2022-04-29 14:37:59 -0700 | |
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committer | 2022-04-29 14:37:59 -0700 | |
commit | 5d8de293c224896a4da99763fce4f9794308caf4 (patch) | |
tree | 06554517aca8f686fdc890da04dd811c1254c995 /arch/riscv/kernel/crash_dump.c | |
parent | fs/proc/kcore.c: remove check of list iterator against head past the loop body (diff) | |
download | linux-5d8de293c224896a4da99763fce4f9794308caf4.tar.gz linux-5d8de293c224896a4da99763fce4f9794308caf4.tar.bz2 linux-5d8de293c224896a4da99763fce4f9794308caf4.zip |
vmcore: convert copy_oldmem_page() to take an iov_iter
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@redhat.com
Link: https://lkml.kernel.org/r/20220408090636.560886-2-bhe@redhat.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/riscv/kernel/crash_dump.c')
-rw-r--r-- | arch/riscv/kernel/crash_dump.c | 26 |
1 files changed, 4 insertions, 22 deletions
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; |