server/mapping.c

   1 /*
   2  * Server-side file mapping management
   3  *
   4  * Copyright (C) 1999 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11
  12 #include "config.h"
  13 #include "winnt.h"
  14 #include "winbase.h"
  15
  16 #include "handle.h"
  17 #include "thread.h"
  18 #include "request.h"
  19
  20 struct mapping
  21 {
  22     struct object  obj;             /* object header */
  23     int            size_high;       /* mapping size */
  24     int            size_low;        /* mapping size */
  25     int            protect;         /* protection flags */
  26     struct file   *file;            /* file mapped */
  27     int            header_size;     /* size of headers (for PE image mapping) */
  28     void          *base;            /* default base addr (for PE image mapping) */
  29     struct file   *shared_file;     /* temp file for shared PE mapping */
  30     int            shared_size;     /* shared mapping total size */
  31 };
  32
  33 static void mapping_dump( struct object *obj, int verbose );
  34 static void mapping_destroy( struct object *obj );
  35
  36 static const struct object_ops mapping_ops =
  37 {
  38     sizeof(struct mapping),      /* size */
  39     mapping_dump,                /* dump */
  40     no_add_queue,                /* add_queue */
  41     NULL,                        /* remove_queue */
  42     NULL,                        /* signaled */
  43     NULL,                        /* satisfied */
  44     NULL,                        /* get_poll_events */
  45     NULL,                        /* poll_event */
  46     no_read_fd,                  /* get_read_fd */
  47     no_write_fd,                 /* get_write_fd */
  48     no_flush,                    /* flush */
  49     no_get_file_info,            /* get_file_info */
  50     mapping_destroy              /* destroy */
  51 };
  52
  53 #ifdef __i386__
  54
  55 /* These are always the same on an i386, and it will be faster this way */
  56 # define page_mask  0xfff
  57 # define page_shift 12
  58 # define init_page_size() /* nothing */
  59
  60 #else  /* __i386__ */
  61
  62 static int page_shift, page_mask;
  63
  64 static void init_page_size(void)
  65 {
  66     int page_size;
  67 # ifdef HAVE_GETPAGESIZE
  68     page_size = getpagesize();
  69 # else
  70 #  ifdef __svr4__
  71     page_size = sysconf(_SC_PAGESIZE);
  72 #  else
  73 #   error Cannot get the page size on this platform
  74 #  endif
  75 # endif
  76     page_mask = page_size - 1;
  77     /* Make sure we have a power of 2 */
  78     assert( !(page_size & page_mask) );
  79     page_shift = 0;
  80     while ((1 << page_shift) != page_size) page_shift++;
  81 }
  82 #endif  /* __i386__ */
  83
  84 #define ROUND_ADDR(addr) \
  85    ((int)(addr) & ~page_mask)
  86
  87 #define ROUND_SIZE(addr,size) \
  88    (((int)(size) + ((int)(addr) & page_mask) + page_mask) & ~page_mask)
  89
  90
  91 /* allocate and fill the temp file for a shared PE image mapping */
  92 static int build_shared_mapping( struct mapping *mapping, int fd,
  93                                  IMAGE_SECTION_HEADER *sec, int nb_sec )
  94 {
  95     int i, max_size, total_size, pos;
  96     char *buffer = NULL;
  97     int shared_fd = -1;
  98
  99     /* compute the total size of the shared mapping */
 100
 101     total_size = max_size = 0;
 102     for (i = 0; i < nb_sec; i++)
 103     {
 104         if ((sec[i].Characteristics & IMAGE_SCN_MEM_SHARED) &&
 105             (sec[i].Characteristics & IMAGE_SCN_MEM_WRITE))
 106         {
 107             int size = ROUND_SIZE( 0, sec[i].Misc.VirtualSize );
 108             if (size > max_size) max_size = size;
 109             total_size += size;
 110         }
 111     }
 112     if (!(mapping->shared_size = total_size)) return 1;  /* nothing to do */
 113
 114     /* create a temp file for the mapping */
 115
 116     if (!(mapping->shared_file = create_temp_file( GENERIC_READ|GENERIC_WRITE ))) goto error;
 117     if (!grow_file( mapping->shared_file, 0, total_size )) goto error;
 118     if ((shared_fd = file_get_mmap_fd( mapping->shared_file )) == -1) goto error;
 119
 120     if (!(buffer = malloc( max_size ))) goto error;
 121
 122     /* copy the shared sections data into the temp file */
 123
 124     for (i = pos = 0; i < nb_sec; i++)
 125     {
 126         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_SHARED)) continue;
 127         if (!(sec[i].Characteristics & IMAGE_SCN_MEM_WRITE)) continue;
 128         if (lseek( shared_fd, pos, SEEK_SET ) != pos) goto error;
 129         pos += ROUND_SIZE( 0, sec[i].Misc.VirtualSize );
 130         if (sec->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA) continue;
 131         if (!sec->PointerToRawData || !sec->SizeOfRawData) continue;
 132         if (lseek( fd, sec[i].PointerToRawData, SEEK_SET ) != sec[i].PointerToRawData) goto error;
 133         if (read( fd, buffer, sec[i].SizeOfRawData ) != sec[i].SizeOfRawData) goto error;
 134         if (write( shared_fd, buffer, sec[i].SizeOfRawData ) != sec[i].SizeOfRawData) goto error;
 135     }
 136     close( shared_fd );
 137     free( buffer );
 138     return 1;
 139
 140  error:
 141     if (shared_fd != -1) close( shared_fd );
 142     if (buffer) free( buffer );
 143     return 0;
 144 }
 145
 146 /* retrieve the mapping parameters for an executable (PE) image */
 147 static int get_image_params( struct mapping *mapping )
 148 {
 149     IMAGE_DOS_HEADER dos;
 150     IMAGE_NT_HEADERS nt;
 151     IMAGE_SECTION_HEADER *sec = NULL;
 152     int fd, filepos, size;
 153
 154     /* load the headers */
 155
 156     if ((fd = file_get_mmap_fd( mapping->file )) == -1) return 0;
 157     filepos = lseek( fd, 0, SEEK_SET );
 158     if (read( fd, &dos, sizeof(dos) ) != sizeof(dos)) goto error;
 159     if (dos.e_magic != IMAGE_DOS_SIGNATURE) goto error;
 160     if (lseek( fd, dos.e_lfanew, SEEK_SET ) == -1) goto error;
 161     if (read( fd, &nt, sizeof(nt) ) != sizeof(nt)) goto error;
 162     if (nt.Signature != IMAGE_NT_SIGNATURE) goto error;
 163
 164     /* load the section headers */
 165
 166     size = sizeof(*sec) * nt.FileHeader.NumberOfSections;
 167     if (!(sec = malloc( size ))) goto error;
 168     if (read( fd, sec, size ) != size) goto error;
 169
 170     if (!build_shared_mapping( mapping, fd, sec, nt.FileHeader.NumberOfSections )) goto error;
 171
 172     mapping->size_low    = ROUND_SIZE( 0, nt.OptionalHeader.SizeOfImage );
 173     mapping->size_high   = 0;
 174     mapping->base        = (void *)nt.OptionalHeader.ImageBase;
 175     mapping->header_size = ROUND_SIZE( mapping->base, nt.OptionalHeader.SizeOfHeaders );
 176     mapping->protect     = VPROT_IMAGE;
 177
 178     /* sanity check */
 179     if (mapping->header_size > mapping->size_low) goto error;
 180
 181     lseek( fd, filepos, SEEK_SET );
 182     close( fd );
 183     free( sec );
 184     return 1;
 185
 186  error:
 187     lseek( fd, filepos, SEEK_SET );
 188     close( fd );
 189     if (sec) free( sec );
 190     set_error( STATUS_INVALID_FILE_FOR_SECTION );
 191     return 0;
 192 }
 193
 194
 195 static struct object *create_mapping( int size_high, int size_low, int protect,
 196                                       int handle, const WCHAR *name, size_t len )
 197 {
 198     struct mapping *mapping;
 199     int access = 0;
 200
 201     if (!page_mask) init_page_size();
 202
 203     if (!(mapping = create_named_object( &mapping_ops, name, len )))
 204         return NULL;
 205     if (get_error() == STATUS_OBJECT_NAME_COLLISION)
 206         return &mapping->obj;  /* Nothing else to do */
 207
 208     mapping->header_size = 0;
 209     mapping->base        = NULL;
 210     mapping->shared_file = NULL;
 211     mapping->shared_size = 0;
 212
 213     if (protect & VPROT_READ) access |= GENERIC_READ;
 214     if (protect & VPROT_WRITE) access |= GENERIC_WRITE;
 215
 216     if (handle != -1)
 217     {
 218         if (!(mapping->file = get_file_obj( current->process, handle, access ))) goto error;
 219         if (protect & VPROT_IMAGE)
 220         {
 221             if (!get_image_params( mapping )) goto error;
 222             return &mapping->obj;
 223         }
 224         if (!size_high && !size_low)
 225         {
 226             struct get_file_info_request req;
 227             struct object *obj = (struct object *)mapping->file;
 228             obj->ops->get_file_info( obj, &req );
 229             size_high = req.size_high;
 230             size_low  = ROUND_SIZE( 0, req.size_low );
 231         }
 232         else if (!grow_file( mapping->file, size_high, size_low )) goto error;
 233     }
 234     else  /* Anonymous mapping (no associated file) */
 235     {
 236         if ((!size_high && !size_low) || (protect & VPROT_IMAGE))
 237         {
 238             set_error( STATUS_INVALID_PARAMETER );
 239             mapping->file = NULL;
 240             goto error;
 241         }
 242         if (!(mapping->file = create_temp_file( access ))) goto error;
 243         if (!grow_file( mapping->file, size_high, size_low )) goto error;
 244     }
 245     mapping->size_high = size_high;
 246     mapping->size_low  = ROUND_SIZE( 0, size_low );
 247     mapping->protect   = protect;
 248     return &mapping->obj;
 249
 250  error:
 251     release_object( mapping );
 252     return NULL;
 253 }
 254
 255 static void mapping_dump( struct object *obj, int verbose )
 256 {
 257     struct mapping *mapping = (struct mapping *)obj;
 258     assert( obj->ops == &mapping_ops );
 259     fprintf( stderr, "Mapping size=%08x%08x prot=%08x file=%p header_size=%08x base=%p "
 260              "shared_file=%p shared_size=%08x ",
 261              mapping->size_high, mapping->size_low, mapping->protect, mapping->file,
 262              mapping->header_size, mapping->base, mapping->shared_file, mapping->shared_size );
 263     dump_object_name( &mapping->obj );
 264     fputc( '\n', stderr );
 265 }
 266
 267 static void mapping_destroy( struct object *obj )
 268 {
 269     struct mapping *mapping = (struct mapping *)obj;
 270     assert( obj->ops == &mapping_ops );
 271     if (mapping->file) release_object( mapping->file );
 272     if (mapping->shared_file) release_object( mapping->shared_file );
 273 }
 274
 275 int get_page_size(void)
 276 {
 277     if (!page_mask) init_page_size();
 278     return page_mask + 1;
 279 }
 280
 281 /* create a file mapping */
 282 DECL_HANDLER(create_mapping)
 283 {
 284     struct object *obj;
 285
 286     req->handle = -1;
 287     if ((obj = create_mapping( req->size_high, req->size_low,
 288                                req->protect, req->file_handle,
 289                                get_req_data(req), get_req_data_size(req) )))
 290     {
 291         int access = FILE_MAP_ALL_ACCESS;
 292         if (!(req->protect & VPROT_WRITE)) access &= ~FILE_MAP_WRITE;
 293         req->handle = alloc_handle( current->process, obj, access, req->inherit );
 294         release_object( obj );
 295     }
 296 }
 297
 298 /* open a handle to a mapping */
 299 DECL_HANDLER(open_mapping)
 300 {
 301     req->handle = open_object( get_req_data(req), get_req_data_size(req),
 302                                &mapping_ops, req->access, req->inherit );
 303 }
 304
 305 /* get a mapping information */
 306 DECL_HANDLER(get_mapping_info)
 307 {
 308     struct mapping *mapping;
 309
 310     if ((mapping = (struct mapping *)get_handle_obj( current->process, req->handle,
 311                                                      0, &mapping_ops )))
 312     {
 313         req->size_high   = mapping->size_high;
 314         req->size_low    = mapping->size_low;
 315         req->protect     = mapping->protect;
 316         req->header_size = mapping->header_size;
 317         req->base        = mapping->base;
 318         req->shared_file = -1;
 319         req->shared_size = mapping->shared_size;
 320         if (mapping->shared_file)
 321             req->shared_file = alloc_handle( current->process, mapping->shared_file,
 322                                              GENERIC_READ|GENERIC_WRITE, 0 );
 323         if (mapping->file) set_reply_fd( current, file_get_mmap_fd( mapping->file ) );
 324         release_object( mapping );
 325     }
 326 }
 327