[PATCH 09/23] maccess: remove probe_read_common and probe_write_common
From: Christoph Hellwig <hch@lst.de>
Date: 2020-05-21 15:23:36
Also in:
bpf, linux-mm, linux-um, lkml
Subsystem:
memory management, memory management - core, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
Each of the helpers has just two callers, which also different in dealing with kernel or userspace pointers. Just open code the logic in the callers. Signed-off-by: Christoph Hellwig <hch@lst.de> --- mm/maccess.c | 63 ++++++++++++++++++++++++---------------------------- 1 file changed, 29 insertions(+), 34 deletions(-)
diff --git a/mm/maccess.c b/mm/maccess.c
index e783ebfccd542..31cf6604e7fff 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c@@ -6,30 +6,6 @@ #include <linux/mm.h> #include <linux/uaccess.h> -static __always_inline long -probe_read_common(void *dst, const void __user *src, size_t size) -{ - long ret; - - pagefault_disable(); - ret = __copy_from_user_inatomic(dst, src, size); - pagefault_enable(); - - return ret ? -EFAULT : 0; -} - -static __always_inline long -probe_write_common(void __user *dst, const void *src, size_t size) -{ - long ret; - - pagefault_disable(); - ret = __copy_to_user_inatomic(dst, src, size); - pagefault_enable(); - - return ret ? -EFAULT : 0; -} - /** * probe_kernel_read(): safely attempt to read from any location * @dst: pointer to the buffer that shall take the data
@@ -69,10 +45,15 @@ long __probe_kernel_read(void *dst, const void *src, size_t size) mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); - ret = probe_read_common(dst, (__force const void __user *)src, size); + pagefault_disable(); + ret = __copy_from_user_inatomic(dst, (__force const void __user *)src, + size); + pagefault_enable(); set_fs(old_fs); - return ret; + if (ret) + return -EFAULT; + return 0; } EXPORT_SYMBOL_GPL(probe_kernel_read);
@@ -91,11 +72,16 @@ long probe_user_read(void *dst, const void __user *src, size_t size) mm_segment_t old_fs = get_fs(); set_fs(USER_DS); - if (access_ok(src, size)) - ret = probe_read_common(dst, src, size); + if (access_ok(src, size)) { + pagefault_disable(); + ret = __copy_from_user_inatomic(dst, src, size); + pagefault_enable(); + } set_fs(old_fs); - return ret; + if (ret) + return -EFAULT; + return 0; } EXPORT_SYMBOL_GPL(probe_user_read);
@@ -114,10 +100,14 @@ long probe_kernel_write(void *dst, const void *src, size_t size) mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); - ret = probe_write_common((__force void __user *)dst, src, size); + pagefault_disable(); + ret = __copy_to_user_inatomic((__force void __user *)dst, src, size); + pagefault_enable(); set_fs(old_fs); - return ret; + if (ret) + return -EFAULT; + return 0; } /**
@@ -135,11 +125,16 @@ long probe_user_write(void __user *dst, const void *src, size_t size) mm_segment_t old_fs = get_fs(); set_fs(USER_DS); - if (access_ok(dst, size)) - ret = probe_write_common(dst, src, size); + if (access_ok(dst, size)) { + pagefault_disable(); + ret = __copy_to_user_inatomic(dst, src, size); + pagefault_enable(); + } set_fs(old_fs); - return ret; + if (ret) + return -EFAULT; + return 0; } /**
--
2.26.2