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Subject[PATCH 17/23] maccess: move user access routines together
Date
Move kernel access vs user access routines together to ease upcoming
ifdefs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
mm/maccess.c | 110 +++++++++++++++++++++++++--------------------------
1 file changed, 55 insertions(+), 55 deletions(-)

diff --git a/mm/maccess.c b/mm/maccess.c
index 81a85c1e71165..ffde1ae86ec51 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c
@@ -46,34 +46,6 @@ long probe_kernel_read(void *dst, const void *src, size_t size)
}
EXPORT_SYMBOL_GPL(probe_kernel_read);

-/**
- * probe_user_read(): safely attempt to read from a user-space location
- * @dst: pointer to the buffer that shall take the data
- * @src: address to read from. This must be a user address.
- * @size: size of the data chunk
- *
- * Safely read from user address @src to the buffer at @dst. If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-long probe_user_read(void *dst, const void __user *src, size_t size)
-{
- long ret = -EFAULT;
- mm_segment_t old_fs = get_fs();
-
- set_fs(USER_DS);
- if (access_ok(src, size)) {
- pagefault_disable();
- ret = __copy_from_user_inatomic(dst, src, size);
- pagefault_enable();
- }
- set_fs(old_fs);
-
- if (ret)
- return -EFAULT;
- return 0;
-}
-EXPORT_SYMBOL_GPL(probe_user_read);
-
/**
* probe_kernel_write(): safely attempt to write to a location
* @dst: address to write to
@@ -99,33 +71,6 @@ long probe_kernel_write(void *dst, const void *src, size_t size)
return 0;
}

-/**
- * probe_user_write(): safely attempt to write to a user-space location
- * @dst: address to write to
- * @src: pointer to the data that shall be written
- * @size: size of the data chunk
- *
- * Safely write to address @dst from the buffer at @src. If a kernel fault
- * happens, handle that and return -EFAULT.
- */
-long probe_user_write(void __user *dst, const void *src, size_t size)
-{
- long ret = -EFAULT;
- mm_segment_t old_fs = get_fs();
-
- set_fs(USER_DS);
- if (access_ok(dst, size)) {
- pagefault_disable();
- ret = __copy_to_user_inatomic(dst, src, size);
- pagefault_enable();
- }
- set_fs(old_fs);
-
- if (ret)
- return -EFAULT;
- return 0;
-}
-
/**
* strncpy_from_kernel_nofault: - Copy a NUL terminated string from unsafe
* address.
@@ -169,6 +114,61 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
return ret ? -EFAULT : src - unsafe_addr;
}

+/**
+ * probe_user_read(): safely attempt to read from a user-space location
+ * @dst: pointer to the buffer that shall take the data
+ * @src: address to read from. This must be a user address.
+ * @size: size of the data chunk
+ *
+ * Safely read from user address @src to the buffer at @dst. If a kernel fault
+ * happens, handle that and return -EFAULT.
+ */
+long probe_user_read(void *dst, const void __user *src, size_t size)
+{
+ long ret = -EFAULT;
+ mm_segment_t old_fs = get_fs();
+
+ set_fs(USER_DS);
+ if (access_ok(src, size)) {
+ pagefault_disable();
+ ret = __copy_from_user_inatomic(dst, src, size);
+ pagefault_enable();
+ }
+ set_fs(old_fs);
+
+ if (ret)
+ return -EFAULT;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(probe_user_read);
+
+/**
+ * probe_user_write(): safely attempt to write to a user-space location
+ * @dst: address to write to
+ * @src: pointer to the data that shall be written
+ * @size: size of the data chunk
+ *
+ * Safely write to address @dst from the buffer at @src. If a kernel fault
+ * happens, handle that and return -EFAULT.
+ */
+long probe_user_write(void __user *dst, const void *src, size_t size)
+{
+ long ret = -EFAULT;
+ mm_segment_t old_fs = get_fs();
+
+ set_fs(USER_DS);
+ if (access_ok(dst, size)) {
+ pagefault_disable();
+ ret = __copy_to_user_inatomic(dst, src, size);
+ pagefault_enable();
+ }
+ set_fs(old_fs);
+
+ if (ret)
+ return -EFAULT;
+ return 0;
+}
+
/**
* strncpy_from_user_nofault: - Copy a NUL terminated string from unsafe user
* address.
--
2.26.2
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