1 2 #include "syslib.h" 3 4 #include <stdlib.h> 5 #include <errno.h> 6 #include <sys/mman.h> 7 #include <minix/sysutil.h> 8 9 void *alloc_contig(size_t len, int flags, phys_bytes *phys) 10 { 11 vir_bytes buf; 12 int mmapflags = MAP_PREALLOC|MAP_CONTIG|MAP_ANON; 13 14 if(flags & AC_LOWER16M) 15 mmapflags |= MAP_LOWER16M; 16 if(flags & AC_LOWER1M) 17 mmapflags |= MAP_LOWER1M; 18 if(flags & AC_ALIGN64K) 19 mmapflags |= MAP_ALIGNMENT_64KB; 20 21 /* First try to get memory with mmap. This is guaranteed 22 * to be page-aligned, and we can tell VM it has to be 23 * pre-allocated and contiguous. 24 */ 25 errno = 0; 26 buf = (vir_bytes) mmap(0, len, PROT_READ|PROT_WRITE, mmapflags, -1, 0); 27 28 if(buf == (vir_bytes) MAP_FAILED) { 29 return NULL; 30 } 31 32 /* Get physical address, if requested. */ 33 if(phys != NULL && sys_umap(SELF, VM_D, buf, len, phys) != OK) 34 panic("sys_umap_data_fb failed"); 35 36 return (void *) buf; 37 } 38 39 int free_contig(void *addr, size_t len) 40 { 41 return munmap(addr, len); 42 } 43 44