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Diffstat (limited to 'qemu/roms/ipxe/src/include/ipxe/uaccess.h')
-rw-r--r-- | qemu/roms/ipxe/src/include/ipxe/uaccess.h | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/include/ipxe/uaccess.h b/qemu/roms/ipxe/src/include/ipxe/uaccess.h new file mode 100644 index 000000000..055bb2ca7 --- /dev/null +++ b/qemu/roms/ipxe/src/include/ipxe/uaccess.h @@ -0,0 +1,396 @@ +#ifndef _IPXE_UACCESS_H +#define _IPXE_UACCESS_H + +/** + * @file + * + * Access to external ("user") memory + * + * iPXE often needs to transfer data between internal and external + * buffers. On i386, the external buffers may require access via a + * different segment, and the buffer address cannot be encoded into a + * simple void * pointer. The @c userptr_t type encapsulates the + * information needed to identify an external buffer, and the + * copy_to_user() and copy_from_user() functions provide methods for + * transferring data between internal and external buffers. + * + * Note that userptr_t is an opaque type; in particular, performing + * arithmetic upon a userptr_t is not allowed. + * + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <stdint.h> +#include <string.h> +#include <ipxe/api.h> +#include <config/ioapi.h> + +/** + * A pointer to a user buffer + * + */ +typedef unsigned long userptr_t; + +/** Equivalent of NULL for user pointers */ +#define UNULL ( ( userptr_t ) 0 ) + +/** + * @defgroup uaccess_trivial Trivial user access API implementations + * + * User access API implementations that can be used by environments in + * which virtual addresses allow access to all of memory. + * + * @{ + * + */ + +/** + * Convert virtual address to user pointer + * + * @v addr Virtual address + * @ret userptr User pointer + */ +static inline __always_inline userptr_t +trivial_virt_to_user ( volatile const void *addr ) { + return ( ( userptr_t ) addr ); +} + +/** + * Convert user pointer to virtual address + * + * @v userptr User pointer + * @v offset Offset from user pointer + * @ret addr Virtual address + * + * This operation is not available under all memory models. + */ +static inline __always_inline void * +trivial_user_to_virt ( userptr_t userptr, off_t offset ) { + return ( ( void * ) userptr + offset ); +} + +/** + * Add offset to user pointer + * + * @v userptr User pointer + * @v offset Offset + * @ret userptr New pointer value + */ +static inline __always_inline userptr_t +trivial_userptr_add ( userptr_t userptr, off_t offset ) { + return ( userptr + offset ); +} + +/** + * Subtract user pointers + * + * @v userptr User pointer + * @v subtrahend User pointer to be subtracted + * @ret offset Offset + */ +static inline __always_inline off_t +trivial_userptr_sub ( userptr_t userptr, userptr_t subtrahend ) { + return ( userptr - subtrahend ); +} + +/** + * Copy data between user buffers + * + * @v dest Destination + * @v dest_off Destination offset + * @v src Source + * @v src_off Source offset + * @v len Length + */ +static inline __always_inline void +trivial_memcpy_user ( userptr_t dest, off_t dest_off, + userptr_t src, off_t src_off, size_t len ) { + memcpy ( ( ( void * ) dest + dest_off ), + ( ( void * ) src + src_off ), len ); +} + +/** + * Copy data between user buffers, allowing for overlap + * + * @v dest Destination + * @v dest_off Destination offset + * @v src Source + * @v src_off Source offset + * @v len Length + */ +static inline __always_inline void +trivial_memmove_user ( userptr_t dest, off_t dest_off, + userptr_t src, off_t src_off, size_t len ) { + memmove ( ( ( void * ) dest + dest_off ), + ( ( void * ) src + src_off ), len ); +} + +/** + * Compare data between user buffers + * + * @v first First buffer + * @v first_off First buffer offset + * @v second Second buffer + * @v second_off Second buffer offset + * @v len Length + * @ret diff Difference + */ +static inline __always_inline int +trivial_memcmp_user ( userptr_t first, off_t first_off, + userptr_t second, off_t second_off, size_t len ) { + return memcmp ( ( ( void * ) first + first_off ), + ( ( void * ) second + second_off ), len ); +} + +/** + * Fill user buffer with a constant byte + * + * @v buffer User buffer + * @v offset Offset within buffer + * @v c Constant byte with which to fill + * @v len Length + */ +static inline __always_inline void +trivial_memset_user ( userptr_t buffer, off_t offset, int c, size_t len ) { + memset ( ( ( void * ) buffer + offset ), c, len ); +} + +/** + * Find length of NUL-terminated string in user buffer + * + * @v buffer User buffer + * @v offset Offset within buffer + * @ret len Length of string (excluding NUL) + */ +static inline __always_inline size_t +trivial_strlen_user ( userptr_t buffer, off_t offset ) { + return strlen ( ( void * ) buffer + offset ); +} + +/** + * Find character in user buffer + * + * @v buffer User buffer + * @v offset Starting offset within buffer + * @v c Character to search for + * @v len Length of user buffer + * @ret offset Offset of character, or <0 if not found + */ +static inline __always_inline off_t +trivial_memchr_user ( userptr_t buffer, off_t offset, int c, size_t len ) { + void *found; + + found = memchr ( ( ( void * ) buffer + offset ), c, len ); + return ( found ? ( found - ( void * ) buffer ) : -1 ); +} + +/** @} */ + +/** + * Calculate static inline user access API function name + * + * @v _prefix Subsystem prefix + * @v _api_func API function + * @ret _subsys_func Subsystem API function + */ +#define UACCESS_INLINE( _subsys, _api_func ) \ + SINGLE_API_INLINE ( UACCESS_PREFIX_ ## _subsys, _api_func ) + +/** + * Provide an user access API implementation + * + * @v _prefix Subsystem prefix + * @v _api_func API function + * @v _func Implementing function + */ +#define PROVIDE_UACCESS( _subsys, _api_func, _func ) \ + PROVIDE_SINGLE_API ( UACCESS_PREFIX_ ## _subsys, _api_func, _func ) + +/** + * Provide a static inline user access API implementation + * + * @v _prefix Subsystem prefix + * @v _api_func API function + */ +#define PROVIDE_UACCESS_INLINE( _subsys, _api_func ) \ + PROVIDE_SINGLE_API_INLINE ( UACCESS_PREFIX_ ## _subsys, _api_func ) + +/* Include all architecture-independent user access API headers */ +#include <ipxe/efi/efi_uaccess.h> +#include <ipxe/linux/linux_uaccess.h> + +/* Include all architecture-dependent user access API headers */ +#include <bits/uaccess.h> + +/** + * Convert physical address to user pointer + * + * @v phys_addr Physical address + * @ret userptr User pointer + */ +userptr_t phys_to_user ( unsigned long phys_addr ); + +/** + * Convert user pointer to physical address + * + * @v userptr User pointer + * @v offset Offset from user pointer + * @ret phys_addr Physical address + */ +unsigned long user_to_phys ( userptr_t userptr, off_t offset ); + +/** + * Convert virtual address to user pointer + * + * @v addr Virtual address + * @ret userptr User pointer + */ +userptr_t virt_to_user ( volatile const void *addr ); + +/** + * Convert user pointer to virtual address + * + * @v userptr User pointer + * @v offset Offset from user pointer + * @ret addr Virtual address + * + * This operation is not available under all memory models. + */ +void * user_to_virt ( userptr_t userptr, off_t offset ); + +/** + * Add offset to user pointer + * + * @v userptr User pointer + * @v offset Offset + * @ret userptr New pointer value + */ +userptr_t userptr_add ( userptr_t userptr, off_t offset ); + +/** + * Subtract user pointers + * + * @v userptr User pointer + * @v subtrahend User pointer to be subtracted + * @ret offset Offset + */ +off_t userptr_sub ( userptr_t userptr, userptr_t subtrahend ); + +/** + * Convert virtual address to a physical address + * + * @v addr Virtual address + * @ret phys_addr Physical address + */ +static inline __always_inline unsigned long +virt_to_phys ( volatile const void *addr ) { + return user_to_phys ( virt_to_user ( addr ), 0 ); +} + +/** + * Convert physical address to a virtual address + * + * @v addr Virtual address + * @ret phys_addr Physical address + * + * This operation is not available under all memory models. + */ +static inline __always_inline void * phys_to_virt ( unsigned long phys_addr ) { + return user_to_virt ( phys_to_user ( phys_addr ), 0 ); +} + +/** + * Copy data between user buffers + * + * @v dest Destination + * @v dest_off Destination offset + * @v src Source + * @v src_off Source offset + * @v len Length + */ +void memcpy_user ( userptr_t dest, off_t dest_off, + userptr_t src, off_t src_off, size_t len ); + +/** + * Copy data to user buffer + * + * @v dest Destination + * @v dest_off Destination offset + * @v src Source + * @v len Length + */ +static inline __always_inline void +copy_to_user ( userptr_t dest, off_t dest_off, const void *src, size_t len ) { + memcpy_user ( dest, dest_off, virt_to_user ( src ), 0, len ); +} + +/** + * Copy data from user buffer + * + * @v dest Destination + * @v src Source + * @v src_off Source offset + * @v len Length + */ +static inline __always_inline void +copy_from_user ( void *dest, userptr_t src, off_t src_off, size_t len ) { + memcpy_user ( virt_to_user ( dest ), 0, src, src_off, len ); +} + +/** + * Copy data between user buffers, allowing for overlap + * + * @v dest Destination + * @v dest_off Destination offset + * @v src Source + * @v src_off Source offset + * @v len Length + */ +void memmove_user ( userptr_t dest, off_t dest_off, + userptr_t src, off_t src_off, size_t len ); + +/** + * Compare data between user buffers + * + * @v first First buffer + * @v first_off First buffer offset + * @v second Second buffer + * @v second_off Second buffer offset + * @v len Length + * @ret diff Difference + */ +int memcmp_user ( userptr_t first, off_t first_off, + userptr_t second, off_t second_off, size_t len ); + +/** + * Fill user buffer with a constant byte + * + * @v userptr User buffer + * @v offset Offset within buffer + * @v c Constant byte with which to fill + * @v len Length + */ +void memset_user ( userptr_t userptr, off_t offset, int c, size_t len ); + +/** + * Find length of NUL-terminated string in user buffer + * + * @v userptr User buffer + * @v offset Offset within buffer + * @ret len Length of string (excluding NUL) + */ +size_t strlen_user ( userptr_t userptr, off_t offset ); + +/** + * Find character in user buffer + * + * @v userptr User buffer + * @v offset Starting offset within buffer + * @v c Character to search for + * @v len Length of user buffer + * @ret offset Offset of character, or <0 if not found + */ +off_t memchr_user ( userptr_t userptr, off_t offset, int c, size_t len ); + +#endif /* _IPXE_UACCESS_H */ |