1 /* $NetBSD: xen_bus_dma.c,v 1.14 2009/01/24 19:03:12 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 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: xen_bus_dma.c,v 1.14 2009/01/24 19:03:12 bouyer Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/mbuf.h> 41 #include <sys/proc.h> 42 43 #include <machine/bus.h> 44 #include <machine/bus_private.h> 45 46 #include <uvm/uvm_extern.h> 47 48 extern paddr_t avail_end; 49 50 /* Pure 2^n version of get_order */ 51 static inline int get_order(unsigned long size) 52 { 53 int order = -1; 54 size = (size - 1) >> (PAGE_SHIFT - 1); 55 do { 56 size >>= 1; 57 order++; 58 } while (size); 59 return order; 60 } 61 62 static int 63 _xen_alloc_contig(bus_size_t size, bus_size_t alignment, bus_size_t boundary, 64 struct pglist *mlistp, int flags, bus_addr_t low, bus_addr_t high) 65 { 66 int order, i; 67 unsigned long npagesreq, npages, mfn; 68 bus_addr_t pa; 69 struct vm_page *pg, *pgnext; 70 int s, error; 71 #ifdef XEN3 72 struct xen_memory_reservation res; 73 #endif 74 75 /* 76 * When requesting a contigous memory region, the hypervisor will 77 * return a memory range aligned on size. This will automagically 78 * handle "boundary", but the only way to enforce alignment 79 * is to request a memory region of size max(alignment, size). 80 */ 81 order = max(get_order(size), get_order(alignment)); 82 npages = (1 << order); 83 npagesreq = (size >> PAGE_SHIFT); 84 KASSERT(npages >= npagesreq); 85 86 /* get npages from UWM, and give them back to the hypervisor */ 87 error = uvm_pglistalloc(npages << PAGE_SHIFT, 0, avail_end, 0, 0, 88 mlistp, npages, (flags & BUS_DMA_NOWAIT) == 0); 89 if (error) 90 return (error); 91 92 for (pg = mlistp->tqh_first; pg != NULL; pg = pg->pageq.queue.tqe_next) { 93 pa = VM_PAGE_TO_PHYS(pg); 94 mfn = xpmap_ptom(pa) >> PAGE_SHIFT; 95 xpmap_phys_to_machine_mapping[ 96 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = INVALID_P2M_ENTRY; 97 #ifdef XEN3 98 xenguest_handle(res.extent_start) = &mfn; 99 res.nr_extents = 1; 100 res.extent_order = 0; 101 res.domid = DOMID_SELF; 102 if (HYPERVISOR_memory_op(XENMEM_decrease_reservation, &res) 103 != 1) { 104 #ifdef DEBUG 105 printf("xen_alloc_contig: XENMEM_decrease_reservation " 106 "failed!\n"); 107 #endif 108 xpmap_phys_to_machine_mapping[ 109 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn; 110 111 error = ENOMEM; 112 goto failed; 113 } 114 #else 115 if (HYPERVISOR_dom_mem_op(MEMOP_decrease_reservation, 116 &mfn, 1, 0) != 1) { 117 #ifdef DEBUG 118 printf("xen_alloc_contig: MEMOP_decrease_reservation " 119 "failed!\n"); 120 #endif 121 xpmap_phys_to_machine_mapping[ 122 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn; 123 error = ENOMEM; 124 goto failed; 125 } 126 #endif 127 } 128 /* Get the new contiguous memory extent */ 129 #ifdef XEN3 130 xenguest_handle(res.extent_start) = &mfn; 131 res.nr_extents = 1; 132 res.extent_order = order; 133 res.address_bits = get_order(high) + PAGE_SHIFT; 134 res.domid = DOMID_SELF; 135 error = HYPERVISOR_memory_op(XENMEM_increase_reservation, &res); 136 if (error != 1) { 137 #ifdef DEBUG 138 printf("xen_alloc_contig: XENMEM_increase_reservation " 139 "failed: %d (order %d address_bits %d)\n", 140 error, order, res.address_bits); 141 #endif 142 error = ENOMEM; 143 pg = NULL; 144 goto failed; 145 } 146 #else 147 if (HYPERVISOR_dom_mem_op(MEMOP_increase_reservation, 148 &mfn, 1, order) != 1) { 149 #ifdef DEBUG 150 printf("xen_alloc_contig: MEMOP_increase_reservation " 151 "failed!\n"); 152 #endif 153 error = ENOMEM; 154 pg = NULL; 155 goto failed; 156 } 157 #endif 158 s = splvm(); 159 /* Map the new extent in place of the old pages */ 160 for (pg = mlistp->tqh_first, i = 0; pg != NULL; pg = pgnext, i++) { 161 pgnext = pg->pageq.queue.tqe_next; 162 pa = VM_PAGE_TO_PHYS(pg); 163 xpmap_phys_to_machine_mapping[ 164 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn+i; 165 xpq_queue_machphys_update((mfn+i) << PAGE_SHIFT, pa); 166 /* while here, give extra pages back to UVM */ 167 if (i >= npagesreq) { 168 TAILQ_REMOVE(mlistp, pg, pageq.queue); 169 uvm_pagefree(pg); 170 } 171 } 172 /* Flush updates through and flush the TLB */ 173 xpq_queue_tlb_flush(); 174 xpq_flush_queue(); 175 splx(s); 176 return 0; 177 178 failed: 179 /* 180 * Attempt to recover from a failed decrease or increase reservation: 181 * if decrease_reservation failed, we don't have given all pages 182 * back to Xen; give them back to UVM, and get the missing pages 183 * from Xen. 184 * if increase_reservation failed, we expect pg to be NULL and we just 185 * get back the missing pages from Xen one by one. 186 */ 187 /* give back remaining pages to UVM */ 188 for (; pg != NULL; pg = pgnext) { 189 pgnext = pg->pageq.queue.tqe_next; 190 TAILQ_REMOVE(mlistp, pg, pageq.queue); 191 uvm_pagefree(pg); 192 } 193 /* remplace the pages that we already gave to Xen */ 194 s = splvm(); 195 for (pg = mlistp->tqh_first; pg != NULL; pg = pgnext) { 196 pgnext = pg->pageq.queue.tqe_next; 197 #ifdef XEN3 198 xenguest_handle(res.extent_start) = &mfn; 199 res.nr_extents = 1; 200 res.extent_order = 0; 201 res.address_bits = 32; 202 res.domid = DOMID_SELF; 203 if (HYPERVISOR_memory_op(XENMEM_increase_reservation, &res) 204 < 0) { 205 printf("xen_alloc_contig: recovery " 206 "XENMEM_increase_reservation failed!\n"); 207 break; 208 } 209 #else 210 if (HYPERVISOR_dom_mem_op(MEMOP_increase_reservation, 211 &mfn, 1, 0) != 1) { 212 printf("xen_alloc_contig: recovery " 213 "MEMOP_increase_reservation failed!\n"); 214 break; 215 } 216 #endif 217 pa = VM_PAGE_TO_PHYS(pg); 218 xpmap_phys_to_machine_mapping[ 219 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn; 220 xpq_queue_machphys_update((mfn) << PAGE_SHIFT, pa); 221 TAILQ_REMOVE(mlistp, pg, pageq.queue); 222 uvm_pagefree(pg); 223 } 224 /* Flush updates through and flush the TLB */ 225 xpq_queue_tlb_flush(); 226 xpq_flush_queue(); 227 splx(s); 228 return error; 229 } 230 231 232 /* 233 * Allocate physical memory from the given physical address range. 234 * Called by DMA-safe memory allocation methods. 235 * We need our own version to deal with physical vs machine addresses. 236 */ 237 int 238 _xen_bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, 239 bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, 240 int nsegs, int *rsegs, int flags, bus_addr_t low, bus_addr_t high) 241 { 242 bus_addr_t curaddr, lastaddr; 243 struct vm_page *m; 244 struct pglist mlist; 245 int curseg, error; 246 int doingrealloc = 0; 247 248 /* Always round the size. */ 249 size = round_page(size); 250 251 KASSERT((alignment & (alignment - 1)) == 0); 252 KASSERT((boundary & (boundary - 1)) == 0); 253 if (alignment < PAGE_SIZE) 254 alignment = PAGE_SIZE; 255 if (boundary != 0 && boundary < size) 256 return (EINVAL); 257 258 /* 259 * Allocate pages from the VM system. 260 */ 261 error = uvm_pglistalloc(size, 0, avail_end, alignment, boundary, 262 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 263 if (error) 264 return (error); 265 again: 266 267 /* 268 * Compute the location, size, and number of segments actually 269 * returned by the VM code. 270 */ 271 m = mlist.tqh_first; 272 curseg = 0; 273 curaddr = lastaddr = segs[curseg].ds_addr = _BUS_VM_PAGE_TO_BUS(m); 274 if (curaddr < low || curaddr >= high) 275 goto badaddr; 276 segs[curseg].ds_len = PAGE_SIZE; 277 m = m->pageq.queue.tqe_next; 278 if ((segs[curseg].ds_addr & (alignment - 1)) != 0) 279 goto dorealloc; 280 281 for (; m != NULL; m = m->pageq.queue.tqe_next) { 282 curaddr = _BUS_VM_PAGE_TO_BUS(m); 283 if (curaddr < low || curaddr >= high) 284 goto badaddr; 285 if (curaddr == (lastaddr + PAGE_SIZE)) { 286 segs[curseg].ds_len += PAGE_SIZE; 287 if ((lastaddr & boundary) != (curaddr & boundary)) 288 goto dorealloc; 289 } else { 290 curseg++; 291 if (curseg >= nsegs || (curaddr & (alignment - 1)) != 0) 292 goto dorealloc; 293 segs[curseg].ds_addr = curaddr; 294 segs[curseg].ds_len = PAGE_SIZE; 295 } 296 lastaddr = curaddr; 297 } 298 299 *rsegs = curseg + 1; 300 return (0); 301 302 badaddr: 303 #ifdef XEN3 304 if (doingrealloc == 0) 305 goto dorealloc; 306 if (curaddr < low) { 307 /* no way to enforce this */ 308 printf("_xen_bus_dmamem_alloc_range: no way to " 309 "enforce address range (0x%" PRIx64 " - 0x%" PRIx64 ")\n", 310 (uint64_t)low, (uint64_t)high); 311 uvm_pglistfree(&mlist); 312 return EINVAL; 313 } 314 printf("xen_bus_dmamem_alloc_range: " 315 "curraddr=0x%lx > high=0x%lx\n", 316 (u_long)curaddr, (u_long)high); 317 panic("xen_bus_dmamem_alloc_range 1"); 318 #else /* !XEN3 */ 319 /* 320 * If machine addresses are outside the allowed 321 * range we have to bail. Xen2 doesn't offer an 322 * interface to get memory in a specific address 323 * range. 324 */ 325 printf("_xen_bus_dmamem_alloc_range: no way to " 326 "enforce address range\n"); 327 uvm_pglistfree(&mlist); 328 return EINVAL; 329 #endif /* XEN3 */ 330 dorealloc: 331 if (doingrealloc == 1) 332 panic("_xen_bus_dmamem_alloc_range: " 333 "xen_alloc_contig returned " 334 "too much segments"); 335 doingrealloc = 1; 336 /* 337 * Too much segments, or memory doesn't fit 338 * constraints. Free this memory and 339 * get a contigous segment from the hypervisor. 340 */ 341 uvm_pglistfree(&mlist); 342 for (curseg = 0; curseg < nsegs; curseg++) { 343 segs[curseg].ds_addr = 0; 344 segs[curseg].ds_len = 0; 345 } 346 error = _xen_alloc_contig(size, alignment, 347 boundary, &mlist, flags, low, high); 348 if (error) 349 return error; 350 goto again; 351 } 352