minix/lib/libc/sys-minix/mmap.c
Ben Gras 33a7ac7557 vfs: mmap support
. libc: add vfs_mmap, a way for vfs to initiate mmap()s.
	  This is a good special case to have as vfs is a slightly
	  different client from regular user processes. It doesn't do it
	  for itself, and has the dev & inode info already so the callback
	  to VFS for the lookup isn't necessary. So it has different info
	  to have to give to VM.
	. libc: also add minix_mmap64() that accepts a 64-bit offset, even
	  though our off_t is still 32 bit now.
	. On exec() time, try to mmap() in the executable if available.
	  (It is not yet available in this commit.)
	. To support mmap(), add do_vm_call that allows VM to lookup
	  (to ino+dev), do i/o from and close FD's on behalf of other
	  processes.

Change-Id: I831551e45a6781c74313c450eb9c967a68505932
2013-05-31 15:42:00 +00:00

176 lines
3.2 KiB
C

#define _SYSTEM 1
#include <sys/cdefs.h>
#include "namespace.h"
#include <lib.h>
#include <minix/u64.h>
#include <minix/vm.h>
/* INCLUDES HERE */
#ifdef __weak_alias
__weak_alias(vm_remap, _vm_remap)
__weak_alias(vm_unmap, _vm_unmap)
__weak_alias(vm_getphys, _vm_getphys)
__weak_alias(vm_getrefcount, _vm_getrefcount)
__weak_alias(minix_mmap, _minix_mmap)
__weak_alias(minix_munmap, _minix_munmap)
#endif
#include <sys/mman.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
void *minix_mmap_for(endpoint_t forwhom,
void *addr, size_t len, int prot, int flags, int fd, u64_t offset)
{
message m;
int r;
m.VMM_ADDR = (vir_bytes) addr;
m.VMM_LEN = len;
m.VMM_PROT = prot;
m.VMM_FLAGS = flags;
m.VMM_FD = fd;
m.VMM_OFFSET_LO = ex64lo(offset);
if(forwhom != SELF) {
m.VMM_FLAGS |= MAP_THIRDPARTY;
m.VMM_FORWHOM = forwhom;
} else {
m.VMM_OFFSET_HI = ex64hi(offset);
}
r = _syscall(VM_PROC_NR, VM_MMAP, &m);
if(r != OK) {
return MAP_FAILED;
}
return (void *) m.VMM_RETADDR;
}
int minix_vfs_mmap(endpoint_t who, u32_t offset, u32_t len,
u32_t dev, u32_t ino, u16_t fd, u32_t vaddr, u16_t clearend,
u16_t flags)
{
message m;
memset(&m, 0, sizeof(message));
m.m_u.m_vm_vfs.who = who;
m.m_u.m_vm_vfs.offset = offset;
m.m_u.m_vm_vfs.dev = dev;
m.m_u.m_vm_vfs.ino = ino;
m.m_u.m_vm_vfs.vaddr = vaddr;
m.m_u.m_vm_vfs.len = len;
m.m_u.m_vm_vfs.fd = fd;
m.m_u.m_vm_vfs.clearend_and_flags = clearend | flags;
return _syscall(VM_PROC_NR, VM_VFS_MMAP, &m);
}
void *minix_mmap(void *addr, size_t len, int prot, int flags,
int fd, off_t offset)
{
return minix_mmap_for(SELF, addr, len, prot, flags, fd, offset);
}
void *minix_mmap64(void *addr, size_t len, int prot, int flags,
int fd, u64_t offset)
{
return minix_mmap_for(SELF, addr, len, prot, flags, fd, offset);
}
int minix_munmap(void *addr, size_t len)
{
message m;
m.VMUM_ADDR = addr;
m.VMUM_LEN = len;
return _syscall(VM_PROC_NR, VM_MUNMAP, &m);
}
void *vm_remap(endpoint_t d,
endpoint_t s,
void *da,
void *sa,
size_t size)
{
message m;
int r;
m.VMRE_D = d;
m.VMRE_S = s;
m.VMRE_DA = (char *) da;
m.VMRE_SA = (char *) sa;
m.VMRE_SIZE = size;
r = _syscall(VM_PROC_NR, VM_REMAP, &m);
if (r != OK)
return MAP_FAILED;
return (void *) m.VMRE_RETA;
}
void *vm_remap_ro(endpoint_t d,
endpoint_t s,
void *da,
void *sa,
size_t size)
{
message m;
int r;
m.VMRE_D = d;
m.VMRE_S = s;
m.VMRE_DA = (char *) da;
m.VMRE_SA = (char *) sa;
m.VMRE_SIZE = size;
r = _syscall(VM_PROC_NR, VM_REMAP_RO, &m);
if (r != OK)
return MAP_FAILED;
return (void *) m.VMRE_RETA;
}
int vm_unmap(endpoint_t endpt, void *addr)
{
message m;
m.VMUN_ENDPT = endpt;
m.VMUN_ADDR = (long) addr;
return _syscall(VM_PROC_NR, VM_SHM_UNMAP, &m);
}
unsigned long vm_getphys(endpoint_t endpt, void *addr)
{
message m;
int r;
m.VMPHYS_ENDPT = endpt;
m.VMPHYS_ADDR = (long) addr;
r = _syscall(VM_PROC_NR, VM_GETPHYS, &m);
if (r != OK)
return 0;
return m.VMPHYS_RETA;
}
u8_t vm_getrefcount(endpoint_t endpt, void *addr)
{
message m;
int r;
m.VMREFCNT_ENDPT = endpt;
m.VMREFCNT_ADDR = (long) addr;
r = _syscall(VM_PROC_NR, VM_GETREF, &m);
if (r != OK)
return (u8_t) -1;
return (u8_t) m.VMREFCNT_RETC;
}