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loader: Define asm functions instead of inlines for x86-64 syscalls to avoid trouble with register constraints.

This commit is contained in:
Alexandre Julliard 2010-12-18 12:33:29 +01:00
parent 17e66e06d6
commit 61d2d80795
1 changed files with 39 additions and 74 deletions
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113
loader/preloader.c
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@ -371,93 +371,58 @@ __ASM_GLOBAL_FUNC(_start,
"xorq %r11,%r11\n\t"
"ret")
#define SYSCALL_RET(ret) (((ret) < 0 && (ret) > -4096) ? -1 : (ret))
#define SYSCALL_FUNC( name, nr ) \
__ASM_GLOBAL_FUNC( name, \
"movq $" #nr ",%rax\n\t" \
"movq %rcx,%r10\n\t" \
"syscall\n\t" \
"leaq 4096(%rax),%rcx\n\t" \
"movq $-1,%rdx\n\t" \
"cmp $4096,%rcx\n\t" \
"cmovb %rdx,%rax\n\t" \
"ret" )
static inline __attribute__((noreturn)) void wld_exit( int code )
{
for (;;) /* avoid warning */
__asm__ __volatile__( "syscall" : : "a" (SYS_exit), "D" (code) );
}
#define SYSCALL_NOERR( name, nr ) \
__ASM_GLOBAL_FUNC( name, \
"movq $" #nr ",%rax\n\t" \
"syscall\n\t" \
"ret" )
static inline int wld_open( const char *name, int flags )
{
int ret;
__asm__ __volatile__( "syscall" : "=a" (ret) : "0" (SYS_open), "D" (name), "S" (flags) );
return SYSCALL_RET(ret);
}
void wld_exit( int code ) __attribute__((noreturn));
SYSCALL_NOERR( wld_exit, 60 /* SYS_exit */ );
static inline int wld_close( int fd )
{
int ret;
__asm__ __volatile__( "syscall" : "=a" (ret) : "0" (SYS_close), "D" (fd) );
return SYSCALL_RET(ret);
}
ssize_t wld_read( int fd, void *buffer, size_t len );
SYSCALL_FUNC( wld_read, 0 /* SYS_read */ );
static inline ssize_t wld_read( int fd, void *buffer, size_t len )
{
int ret;
__asm__ __volatile__( "syscall"
: "=a" (ret)
: "0" (SYS_read), "D" (fd), "S" (buffer), "d" (len)
: "memory" );
return SYSCALL_RET(ret);
}
ssize_t wld_write( int fd, const void *buffer, size_t len );
SYSCALL_FUNC( wld_write, 1 /* SYS_write */ );
static inline ssize_t wld_write( int fd, const void *buffer, size_t len )
{
int ret;
__asm__ __volatile__( "syscall" : "=a" (ret) : "0" (SYS_write), "D" (fd), "S" (buffer), "d" (len) );
return SYSCALL_RET(ret);
}
int wld_open( const char *name, int flags );
SYSCALL_FUNC( wld_open, 2 /* SYS_open */ );
static inline int wld_mprotect( const void *addr, size_t len, int prot )
{
int ret;
__asm__ __volatile__( "syscall" : "=a" (ret) : "0" (SYS_mprotect), "D" (addr), "S" (len), "d" (prot) );
return SYSCALL_RET(ret);
}
int wld_close( int fd );
SYSCALL_FUNC( wld_close, 3 /* SYS_close */ );
void *wld_mmap( void *start, size_t len, int prot, int flags, int fd, off_t offset );
__ASM_GLOBAL_FUNC( wld_mmap,
"movq %rcx,%r10\n\t"
"movq $9,%rax\n\t" /* SYS_mmap */
"syscall\n\t"
"ret" );
SYSCALL_FUNC( wld_mmap, 9 /* SYS_mmap */ );
static inline uid_t wld_getuid(void)
{
uid_t ret;
__asm__( "syscall" : "=a" (ret) : "0" (SYS_getuid) );
return ret;
}
int wld_mprotect( const void *addr, size_t len, int prot );
SYSCALL_FUNC( wld_mprotect, 10 /* SYS_mprotect */ );
static inline uid_t wld_geteuid(void)
{
uid_t ret;
__asm__( "syscall" : "=a" (ret) : "0" (SYS_geteuid) );
return ret;
}
int wld_prctl( int code, int arg );
SYSCALL_FUNC( wld_prctl, 157 /* SYS_prctl */ );
static inline gid_t wld_getgid(void)
{
gid_t ret;
__asm__( "syscall" : "=a" (ret) : "0" (SYS_getgid) );
return ret;
}
uid_t wld_getuid(void);
SYSCALL_NOERR( wld_getuid, 102 /* SYS_getuid */ );
static inline gid_t wld_getegid(void)
{
gid_t ret;
__asm__( "syscall" : "=a" (ret) : "0" (SYS_getegid) );
return ret;
}
gid_t wld_getgid(void);
SYSCALL_NOERR( wld_getgid, 104 /* SYS_getgid */ );
static inline int wld_prctl( int code, int arg )
{
int ret;
__asm__ __volatile__( "syscall" : "=a" (ret) : "D" (SYS_prctl), "S" (code), "d" (arg) );
return SYSCALL_RET(ret);
}
uid_t wld_geteuid(void);
SYSCALL_NOERR( wld_geteuid, 107 /* SYS_geteuid */ );
gid_t wld_getegid(void);
SYSCALL_NOERR( wld_getegid, 108 /* SYS_getegid */ );
#else
#error preloader not implemented for this CPU