# rtai_shm.h

    00001 /*
    00002  * Copyright (C) 1999-2003 Paolo Mantegazza <mantegazza@aero.polimi.it>
    00003  *
    00004  * This program is free software; you can redistribute it and/or
    00005  * modify it under the terms of the GNU General Public License as
    00006  * published by the Free Software Foundation; either version 2 of the
    00007  * License, or (at your option) any later version.
    00008  *
    00009  * This program is distributed in the hope that it will be useful,
    00010  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    00011  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00012  * GNU General Public License for more details.
    00013  *
    00014  * You should have received a copy of the GNU General Public License
    00015  * along with this program; if not, write to the Free Software
    00016  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
    00017  */
    00018
    00019 #ifndef _RTAI_ASM_I386_SHM_H
    00020 #define _RTAI_ASM_I386_SHM_H
    00021
    00022 #include <asm/pgtable.h>
    00023 #include <asm/io.h>
    00024 #include <asm/rtai_vectors.h>
    00025 #include <rtai_wrappers.h>
    00026
    00027 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
    00028 #define VMALLOC_VMADDR(x) ((unsigned long)(x))
    00029 #endif /* >= 2.6.0 */
    00030
    00031 #ifndef __KERNEL__
    00032
    00033 static inline long long rtai_shmrq(int srq, unsigned long args)
    00034 {
    00035         long long retval;
    00036         RTAI_DO_TRAP(RTAI_SYS_VECTOR, retval, srq, args);
    00037         return retval;
    00038 }
    00039
    00040 #endif /* __KERNEL__ */
    00041
    00042 /* convert virtual user memory address to physical address */
    00043 /* (virt_to_phys only works for kmalloced kernel memory) */
    00044
    00045 static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr)
    00046 {
    00047         unsigned long ret = 0UL;
    00048         pmd_t *pmd;
    00049         pte_t *ptep, pte;
    00050
    00051         if(!pgd_none(*pgd)) {
    00052                 pmd = pmd_offset(pgd, adr);
    00053                 if (!pmd_none(*pmd)) {
    00054 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
    00055                         ptep = pte_offset(pmd, adr);
    00056 #else /* >= 2.6.0 */
    00057                         ptep = pte_offset_kernel(pmd, adr);
    00058 #endif /* < 2.6.0 */
    00059                         pte = *ptep;
    00060                         if(pte_present(pte)){
    00061                                 ret = (unsigned long) page_address(pte_page(pte));
    00062                                 ret |= (adr&(PAGE_SIZE-1));
    00063                         }
    00064                 }
    00065         }
    00066         return ret;
    00067 }
    00068
    00069 static inline unsigned long uvirt_to_bus(unsigned long adr)
    00070 {
    00071         unsigned long kva, ret;
    00072
    00073         kva = uvirt_to_kva(pgd_offset(current->mm, adr), adr);
    00074         ret = virt_to_bus((void *)kva);
    00075
    00076         return ret;
    00077 }
    00078
    00079 static inline unsigned long kvirt_to_bus(unsigned long adr)
    00080 {
    00081         unsigned long va, kva, ret;
    00082
    00083         va = VMALLOC_VMADDR(adr);
    00084         kva = uvirt_to_kva(pgd_offset_k(va), va);
    00085         ret = virt_to_bus((void *)kva);
    00086
    00087         return ret;
    00088 }
    00089
    00090 static inline unsigned long kvirt_to_pa(unsigned long adr)
    00091 {
    00092         unsigned long va, kva, ret;
    00093
    00094         va = VMALLOC_VMADDR(adr);
    00095         kva = uvirt_to_kva(pgd_offset_k(va), va);
    00096         ret = __pa(kva);
    00097
    00098         return ret;
    00099 }
    00100
    00101 #endif  /* !_RTAI_ASM_I386_SHM_H */