-/*
- * Copyright (C) 2010 Piotr Jaroszyński <p.jaroszynski@gmail.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
#ifndef _IPXE_LINUX_UACCESS_H
#define _IPXE_LINUX_UACCESS_H
-FILE_LICENCE(GPL2_OR_LATER);
-
/** @file
*
- * iPXE user access API for linux
+ * iPXE user access API for Linux
+ *
+ * We run with no distinction between internal and external addresses,
+ * so can use trivial_virt_to_user() et al.
*
- * In linux userspace virtual == user == phys addresses.
- * Physical addresses also being the same is wrong, but there is no general way
- * of converting userspace addresses to physical as what appears to be
- * contiguous in userspace is physically fragmented.
- * Currently only the DMA memory is special-cased, but its conversion to bus
- * addresses is done in phys_to_bus.
- * This is known to break virtio as it is passing phys addresses to the virtual
- * device.
+ * We have no concept of the underlying physical addresses, since
+ * these are not exposed to userspace. We provide a stub
+ * implementation of user_to_phys() since this is required by
+ * alloc_memblock(). We provide no implementation of phys_to_user();
+ * any code attempting to access physical addresses will therefore
+ * (correctly) fail to link.
*/
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
#ifdef UACCESS_LINUX
#define UACCESS_PREFIX_linux
#else
#define UACCESS_PREFIX_linux __linux_
#endif
-static inline __always_inline userptr_t
-UACCESS_INLINE(linux, phys_to_user)(unsigned long phys_addr)
-{
- return phys_addr;
-}
-
+/**
+ * Convert user buffer to physical address
+ *
+ * @v userptr User pointer
+ * @v offset Offset from user pointer
+ * @ret phys_addr Physical address
+ */
static inline __always_inline unsigned long
-UACCESS_INLINE(linux, user_to_phys)(userptr_t userptr, off_t offset)
-{
- return userptr + offset;
+UACCESS_INLINE ( linux, user_to_phys ) ( userptr_t userptr, off_t offset ) {
+
+ /* We do not know the real underlying physical address. We
+ * provide this stub implementation only because it is
+ * required by alloc_memblock() (which allocates memory with
+ * specified physical address alignment). We assume that the
+ * low-order bits of virtual addresses match the low-order
+ * bits of physical addresses, and so simply returning the
+ * virtual address will suffice for the purpose of determining
+ * alignment.
+ */
+ return ( userptr + offset );
}
static inline __always_inline userptr_t
-UACCESS_INLINE(linux, virt_to_user)(volatile const void *addr)
-{
- return trivial_virt_to_user(addr);
+UACCESS_INLINE ( linux, virt_to_user ) ( volatile const void *addr ) {
+ return trivial_virt_to_user ( addr );
}
static inline __always_inline void *
-UACCESS_INLINE(linux, user_to_virt)(userptr_t userptr, off_t offset)
-{
- return trivial_user_to_virt(userptr, offset);
+UACCESS_INLINE ( linux, user_to_virt ) ( userptr_t userptr, off_t offset ) {
+ return trivial_user_to_virt ( userptr, offset );
}
static inline __always_inline userptr_t
-UACCESS_INLINE(linux, userptr_add)(userptr_t userptr, off_t offset)
-{
- return trivial_userptr_add(userptr, offset);
+UACCESS_INLINE ( linux, userptr_add ) ( userptr_t userptr, off_t offset ) {
+ return trivial_userptr_add ( userptr, offset );
}
static inline __always_inline off_t
-UACCESS_INLINE(linux, userptr_sub)(userptr_t userptr, userptr_t subtrahend)
-{
+UACCESS_INLINE ( linux, userptr_sub ) ( userptr_t userptr,
+ userptr_t subtrahend ) {
return trivial_userptr_sub ( userptr, subtrahend );
}
static inline __always_inline void
-UACCESS_INLINE(linux, memcpy_user)(userptr_t dest, off_t dest_off, userptr_t src, off_t src_off, size_t len)
-{
- trivial_memcpy_user(dest, dest_off, src, src_off, len);
+UACCESS_INLINE ( linux, memcpy_user ) ( userptr_t dest, off_t dest_off,
+ userptr_t src, off_t src_off,
+ size_t len ) {
+ trivial_memcpy_user ( dest, dest_off, src, src_off, len );
}
static inline __always_inline void
-UACCESS_INLINE(linux, memmove_user)(userptr_t dest, off_t dest_off, userptr_t src, off_t src_off, size_t len)
-{
- trivial_memmove_user(dest, dest_off, src, src_off, len);
+UACCESS_INLINE ( linux, memmove_user ) ( userptr_t dest, off_t dest_off,
+ userptr_t src, off_t src_off,
+ size_t len ) {
+ trivial_memmove_user ( dest, dest_off, src, src_off, len );
}
static inline __always_inline int
-UACCESS_INLINE(linux, memcmp_user)(userptr_t first, off_t first_off, userptr_t second, off_t second_off, size_t len)
-{
- return trivial_memcmp_user(first, first_off, second, second_off, len);
+UACCESS_INLINE ( linux, memcmp_user ) ( userptr_t first, off_t first_off,
+ userptr_t second, off_t second_off,
+ size_t len ) {
+ return trivial_memcmp_user ( first, first_off, second, second_off, len);
}
static inline __always_inline void
-UACCESS_INLINE(linux, memset_user)(userptr_t buffer, off_t offset, int c, size_t len)
-{
- trivial_memset_user(buffer, offset, c, len);
+UACCESS_INLINE ( linux, memset_user ) ( userptr_t buffer, off_t offset,
+ int c, size_t len ) {
+ trivial_memset_user ( buffer, offset, c, len );
}
static inline __always_inline size_t
-UACCESS_INLINE(linux, strlen_user)(userptr_t buffer, off_t offset)
-{
- return trivial_strlen_user(buffer, offset);
+UACCESS_INLINE ( linux, strlen_user ) ( userptr_t buffer, off_t offset ) {
+ return trivial_strlen_user ( buffer, offset );
}
static inline __always_inline off_t
-UACCESS_INLINE(linux, memchr_user)(userptr_t buffer, off_t offset, int c, size_t len)
-{
- return trivial_memchr_user(buffer, offset, c, len);
+UACCESS_INLINE ( linux, memchr_user ) ( userptr_t buffer, off_t offset,
+ int c, size_t len ) {
+ return trivial_memchr_user ( buffer, offset, c, len );
}
#endif /* _IPXE_LINUX_UACCESS_H */
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