1 /* $NetBSD: xen_bus_dma.c,v 1.6 2006/01/15 22:09:52 bouyer Exp $ */ 2 /* NetBSD bus_dma.c,v 1.21 2005/04/16 07:53:35 yamt Exp */ 3 4 /*- 5 * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Charles M. Hannum and by Jason R. Thorpe of the Numerical Aerospace 10 * Simulation Facility, NASA Ames Research Center. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the NetBSD 23 * Foundation, Inc. and its contributors. 24 * 4. Neither the name of The NetBSD Foundation nor the names of its 25 * contributors may be used to endorse or promote products derived 26 * from this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 29 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 30 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 31 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 32 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 38 * POSSIBILITY OF SUCH DAMAGE. 39 */ 40 41 #include <sys/cdefs.h> 42 __KERNEL_RCSID(0, "$NetBSD: xen_bus_dma.c,v 1.6 2006/01/15 22:09:52 bouyer Exp $"); 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/proc.h> 50 51 #include <machine/bus.h> 52 #include <machine/bus_private.h> 53 54 #include <uvm/uvm_extern.h> 55 56 extern paddr_t avail_end; 57 58 /* Pure 2^n version of get_order */ 59 static inline int get_order(unsigned long size) 60 { 61 int order = -1; 62 size = (size - 1) >> (PAGE_SHIFT - 1); 63 do { 64 size >>= 1; 65 order++; 66 } while (size); 67 return order; 68 } 69 70 static int 71 _xen_alloc_contig(bus_size_t size, bus_size_t alignment, bus_size_t boundary, 72 struct pglist *mlistp, int flags) 73 { 74 int order, i; 75 unsigned long npagesreq, npages, mfn; 76 bus_addr_t pa; 77 struct vm_page *pg, *pgnext; 78 struct pglist freelist; 79 int s, error; 80 #ifdef XEN3 81 struct xen_memory_reservation res; 82 #endif 83 84 TAILQ_INIT(&freelist); 85 86 /* 87 * When requesting a contigous memory region, the hypervisor will 88 * return a memory range aligned on size. This will automagically 89 * handle "boundary", but the only way to enforce alignment 90 * is to request a memory region of size max(alignment, size). 91 */ 92 order = max(get_order(size), get_order(alignment)); 93 npages = (1 << order); 94 npagesreq = (size >> PAGE_SHIFT); 95 KASSERT(npages >= npagesreq); 96 97 /* get npages from UWM, and give them back to the hypervisor */ 98 error = uvm_pglistalloc(npages << PAGE_SHIFT, 0, avail_end, 0, 0, 99 mlistp, npages, (flags & BUS_DMA_NOWAIT) == 0); 100 if (error) 101 return (error); 102 103 for (pg = mlistp->tqh_first; pg != NULL; pg = pg->pageq.tqe_next) { 104 pa = VM_PAGE_TO_PHYS(pg); 105 mfn = xpmap_ptom(pa) >> PAGE_SHIFT; 106 xpmap_phys_to_machine_mapping[ 107 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = INVALID_P2M_ENTRY; 108 #ifdef XEN3 109 res.extent_start = &mfn; 110 res.nr_extents = 1; 111 res.extent_order = 0; 112 res.domid = DOMID_SELF; 113 if (HYPERVISOR_memory_op(XENMEM_decrease_reservation, &res) 114 < 0) { 115 printf("xen_alloc_contig: XENMEM_decrease_reservation " 116 "failed!\n"); 117 return ENOMEM; 118 } 119 #else 120 if (HYPERVISOR_dom_mem_op(MEMOP_decrease_reservation, 121 &mfn, 1, 0) != 1) { 122 printf("xen_alloc_contig: MEMOP_decrease_reservation " 123 "failed!\n"); 124 return ENOMEM; 125 } 126 #endif 127 } 128 /* Get the new contiguous memory extent */ 129 #ifdef XEN3 130 res.extent_start = &mfn; 131 res.nr_extents = 1; 132 res.extent_order = order; 133 res.address_bits = 31; 134 res.domid = DOMID_SELF; 135 if (HYPERVISOR_memory_op(XENMEM_increase_reservation, &res) < 0) { 136 printf("xen_alloc_contig: XENMEM_increase_reservation " 137 "failed!\n"); 138 return ENOMEM; 139 } 140 #else 141 if (HYPERVISOR_dom_mem_op(MEMOP_increase_reservation, 142 &mfn, 1, order) != 1) { 143 printf("xen_alloc_contig: MEMOP_increase_reservation " 144 "failed!\n"); 145 return ENOMEM; 146 } 147 #endif 148 s = splvm(); 149 /* Map the new extent in place of the old pages */ 150 for (pg = mlistp->tqh_first, i = 0; pg != NULL; pg = pgnext, i++) { 151 pgnext = pg->pageq.tqe_next; 152 pa = VM_PAGE_TO_PHYS(pg); 153 xpmap_phys_to_machine_mapping[ 154 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn+i; 155 xpq_queue_machphys_update((mfn+i) << PAGE_SHIFT, pa); 156 /* while here, give extra pages back to UVM */ 157 if (i >= npagesreq) { 158 TAILQ_REMOVE(mlistp, pg, pageq); 159 uvm_pagefree(pg); 160 } 161 162 } 163 /* Flush updates through and flush the TLB */ 164 xpq_queue_tlb_flush(); 165 xpq_flush_queue(); 166 splx(s); 167 return 0; 168 } 169 170 171 /* 172 * Allocate physical memory from the given physical address range. 173 * Called by DMA-safe memory allocation methods. 174 * We need our own version to deal with physical vs machine addresses. 175 */ 176 int 177 _xen_bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, 178 bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, 179 int nsegs, int *rsegs, int flags, bus_addr_t low, bus_addr_t high) 180 { 181 paddr_t curaddr, lastaddr; 182 bus_addr_t bus_curaddr, bus_lastaddr; 183 struct vm_page *m; 184 struct pglist mlist; 185 int curseg, error; 186 int doingrealloc = 0; 187 188 /* Always round the size. */ 189 size = round_page(size); 190 191 KASSERT((alignment & (alignment - 1)) == 0); 192 KASSERT((boundary & (boundary - 1)) == 0); 193 if (alignment < PAGE_SIZE) 194 alignment = PAGE_SIZE; 195 if (boundary != 0 && boundary < size) 196 return (EINVAL); 197 198 /* 199 * Allocate pages from the VM system. 200 */ 201 error = uvm_pglistalloc(size, 0, avail_end, alignment, boundary, 202 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 203 if (error) 204 return (error); 205 again: 206 207 /* 208 * Compute the location, size, and number of segments actually 209 * returned by the VM code. 210 */ 211 m = mlist.tqh_first; 212 curseg = 0; 213 lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m); 214 segs[curseg].ds_len = PAGE_SIZE; 215 m = m->pageq.tqe_next; 216 if ((_BUS_PHYS_TO_BUS(segs[curseg].ds_addr) & (alignment - 1)) != 0) 217 goto dorealloc; 218 219 for (; m != NULL; m = m->pageq.tqe_next) { 220 curaddr = VM_PAGE_TO_PHYS(m); 221 bus_curaddr = _BUS_PHYS_TO_BUS(curaddr); 222 bus_lastaddr = _BUS_PHYS_TO_BUS(lastaddr); 223 if ((bus_lastaddr < low || bus_lastaddr >= high) || 224 (bus_curaddr < low || bus_curaddr >= high)) { 225 /* 226 * If machine addresses are outside the allowed 227 * range we have to bail. Xen2 doesn't offer an 228 * interface to get memory in a specific address 229 * range. 230 */ 231 printf("_xen_bus_dmamem_alloc_range: no way to " 232 "enforce address range\n"); 233 uvm_pglistfree(&mlist); 234 return EINVAL; 235 } 236 if (bus_curaddr == (bus_lastaddr + PAGE_SIZE)) { 237 segs[curseg].ds_len += PAGE_SIZE; 238 if ((bus_lastaddr & boundary) != 239 (bus_curaddr & boundary)) 240 goto dorealloc; 241 } 242 else { 243 curseg++; 244 if (curseg >= nsegs || 245 (bus_curaddr & (alignment - 1)) != 0) { 246 dorealloc: 247 if (doingrealloc == 1) 248 panic("_xen_bus_dmamem_alloc_range: " 249 "xen_alloc_contig returned " 250 "too much segments"); 251 doingrealloc = 1; 252 /* 253 * Too much segments. Free this memory and 254 * get a contigous segment from the hypervisor. 255 */ 256 uvm_pglistfree(&mlist); 257 for (curseg = 0; curseg < nsegs; curseg++) { 258 segs[curseg].ds_addr = 0; 259 segs[curseg].ds_len = 0; 260 } 261 error = _xen_alloc_contig(size, alignment, 262 boundary, &mlist, flags); 263 if (error) 264 return error; 265 goto again; 266 } 267 segs[curseg].ds_addr = curaddr; 268 segs[curseg].ds_len = PAGE_SIZE; 269 } 270 lastaddr = curaddr; 271 } 272 273 *rsegs = curseg + 1; 274 275 return (0); 276 } 277