kernel/system/do_umap.c

   1 /* The kernel call implemented in this file:
   2  *   m_type:    SYS_UMAP
   3  *
   4  * The parameters for this kernel call are:
   5  *    m5_i1:    CP_SRC_PROC_NR  (process number)
   6  *    m5_s1:    CP_SRC_SPACE    (segment where address is: T, D, or S)
   7  *    m5_l1:    CP_SRC_ADDR     (virtual address)
   8  *    m5_l2:    CP_DST_ADDR     (returns physical address)
   9  *    m5_l3:    CP_NR_BYTES     (size of datastructure)
  10  */
  11
  12 #include "kernel/system.h"
  13
  14 #include <minix/endpoint.h>
  15
  16 #if USE_UMAP
  17
  18 /*==========================================================================*
  19  *                              do_umap                                     *
  20  *==========================================================================*/
  21 PUBLIC int do_umap(struct proc * caller, message * m_ptr)
  22 {
  23 /* Map virtual address to physical, for non-kernel processes. */
  24   int seg_type = m_ptr->CP_SRC_SPACE & SEGMENT_TYPE;
  25   int seg_index = m_ptr->CP_SRC_SPACE & SEGMENT_INDEX;
  26   vir_bytes offset = m_ptr->CP_SRC_ADDR;
  27   int count = m_ptr->CP_NR_BYTES;
  28   int endpt = (int) m_ptr->CP_SRC_ENDPT;
  29   int proc_nr, r;
  30   int naughty = 0;
  31   phys_bytes phys_addr = 0, lin_addr = 0;
  32   struct proc *targetpr;
  33
  34   /* Verify process number. */
  35   if (endpt == SELF)
  36         proc_nr = _ENDPOINT_P(caller->p_endpoint);
  37   else
  38         if (! isokendpt(endpt, &proc_nr))
  39                 return(EINVAL);
  40   targetpr = proc_addr(proc_nr);
  41
  42   /* See which mapping should be made. */
  43   switch(seg_type) {
  44   case LOCAL_SEG:
  45       phys_addr = lin_addr = umap_local(targetpr, seg_index, offset, count);
  46       if(!lin_addr) return EFAULT;
  47       naughty = 1;
  48       break;
  49   case REMOTE_SEG:
  50       phys_addr = lin_addr = umap_remote(targetpr, seg_index, offset, count);
  51       if(!lin_addr) return EFAULT;
  52       naughty = 1;
  53       break;
  54   case LOCAL_VM_SEG:
  55     if(seg_index == MEM_GRANT) {
  56         vir_bytes newoffset;
  57         endpoint_t newep;
  58         int new_proc_nr;
  59         cp_grant_id_t grant = (cp_grant_id_t) offset;
  60
  61         if(verify_grant(targetpr->p_endpoint, ANY, grant, count, 0, 0,
  62                 &newoffset, &newep) != OK) {
  63                 printf("SYSTEM: do_umap: verify_grant in %s, grant %d, bytes 0x%lx, failed, caller %s\n", targetpr->p_name, offset, count, caller->p_name);
  64                 proc_stacktrace(caller);
  65                 return EFAULT;
  66         }
  67
  68         if(!isokendpt(newep, &new_proc_nr)) {
  69                 printf("SYSTEM: do_umap: isokendpt failed\n");
  70                 return EFAULT;
  71         }
  72
  73         /* New lookup. */
  74         offset = newoffset;
  75         targetpr = proc_addr(new_proc_nr);
  76         seg_index = D;
  77       }
  78
  79       if(seg_index == T || seg_index == D || seg_index == S) {
  80         phys_addr = lin_addr = umap_local(targetpr, seg_index, offset, count);
  81       } else {
  82         printf("SYSTEM: bogus seg type 0x%lx\n", seg_index);
  83         return EFAULT;
  84       }
  85       if(!lin_addr) {
  86         printf("SYSTEM:do_umap: umap_local failed\n");
  87         return EFAULT;
  88       }
  89       if(vm_lookup(targetpr, lin_addr, &phys_addr, NULL) != OK) {
  90         printf("SYSTEM:do_umap: vm_lookup failed\n");
  91         return EFAULT;
  92       }
  93       if(phys_addr == 0)
  94         panic("vm_lookup returned zero physical address");
  95       break;
  96   default:
  97       if((r=arch_umap(targetpr, offset, count, seg_type, &lin_addr))
  98         != OK)
  99         return r;
 100       phys_addr = lin_addr;
 101   }
 102
 103   if(vm_running && !vm_contiguous(targetpr, lin_addr, count)) {
 104         printf("SYSTEM:do_umap: not contiguous\n");
 105         return EFAULT;
 106   }
 107
 108   m_ptr->CP_DST_ADDR = phys_addr;
 109   if(naughty || phys_addr == 0) {
 110           printf("kernel: umap 0x%x done by %d / %s, pc 0x%lx, 0x%lx -> 0x%lx\n",
 111                 seg_type, caller->p_endpoint, caller->p_name,
 112                 caller->p_reg.pc, offset, phys_addr);
 113         printf("caller stack: ");
 114         proc_stacktrace(caller);
 115   }
 116   return (phys_addr == 0) ? EFAULT: OK;
 117 }
 118
 119 #endif /* USE_UMAP */