xen_bus_dma.c revision 1.11.6.1
1 /* $NetBSD: xen_bus_dma.c,v 1.11.6.1 2009/01/19 13:17:12 skrll 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 1.11.6.1 2009/01/19 13:17:12 skrll 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 < 0) { 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 if (HYPERVISOR_memory_op(XENMEM_increase_reservation, &res) < 0) { 136 #ifdef DEBUG 137 printf("xen_alloc_contig: XENMEM_increase_reservation " 138 "failed!\n"); 139 #endif 140 error = ENOMEM; 141 pg = NULL; 142 goto failed; 143 } 144 #else 145 if (HYPERVISOR_dom_mem_op(MEMOP_increase_reservation, 146 &mfn, 1, order) != 1) { 147 #ifdef DEBUG 148 printf("xen_alloc_contig: MEMOP_increase_reservation " 149 "failed!\n"); 150 #endif 151 error = ENOMEM; 152 pg = NULL; 153 goto failed; 154 } 155 #endif 156 s = splvm(); 157 /* Map the new extent in place of the old pages */ 158 for (pg = mlistp->tqh_first, i = 0; pg != NULL; pg = pgnext, i++) { 159 pgnext = pg->pageq.queue.tqe_next; 160 pa = VM_PAGE_TO_PHYS(pg); 161 xpmap_phys_to_machine_mapping[ 162 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn+i; 163 xpq_queue_machphys_update((mfn+i) << PAGE_SHIFT, pa); 164 /* while here, give extra pages back to UVM */ 165 if (i >= npagesreq) { 166 TAILQ_REMOVE(mlistp, pg, pageq.queue); 167 uvm_pagefree(pg); 168 } 169 170 } 171 /* Flush updates through and flush the TLB */ 172 xpq_queue_tlb_flush(); 173 xpq_flush_queue(); 174 splx(s); 175 return 0; 176 177 failed: 178 /* 179 * Attempt to recover from a failed decrease or increase reservation: 180 * if decrease_reservation failed, we don't have given all pages 181 * back to Xen; give them back to UVM, and get the missing pages 182 * from Xen. 183 * if increase_reservation failed, we expect pg to be NULL and we just 184 * get back the missing pages from Xen one by one. 185 */ 186 /* give back remaining pages to UVM */ 187 for (; pg != NULL; pg = pgnext) { 188 pgnext = pg->pageq.queue.tqe_next; 189 TAILQ_REMOVE(mlistp, pg, pageq.queue); 190 uvm_pagefree(pg); 191 } 192 /* remplace the pages that we already gave to Xen */ 193 s = splvm(); 194 for (pg = mlistp->tqh_first; pg != NULL; pg = pgnext) { 195 pgnext = pg->pageq.queue.tqe_next; 196 #ifdef XEN3 197 xenguest_handle(res.extent_start) = &mfn; 198 res.nr_extents = 1; 199 res.extent_order = 0; 200 res.address_bits = 32; 201 res.domid = DOMID_SELF; 202 if (HYPERVISOR_memory_op(XENMEM_increase_reservation, &res) 203 < 0) { 204 printf("xen_alloc_contig: recovery " 205 "XENMEM_increase_reservation failed!\n"); 206 break; 207 } 208 #else 209 if (HYPERVISOR_dom_mem_op(MEMOP_increase_reservation, 210 &mfn, 1, 0) != 1) { 211 printf("xen_alloc_contig: recovery " 212 "MEMOP_increase_reservation failed!\n"); 213 break; 214 } 215 #endif 216 pa = VM_PAGE_TO_PHYS(pg); 217 xpmap_phys_to_machine_mapping[ 218 (pa - XPMAP_OFFSET) >> PAGE_SHIFT] = mfn; 219 xpq_queue_machphys_update((mfn) << PAGE_SHIFT, pa); 220 TAILQ_REMOVE(mlistp, pg, pageq.queue); 221 uvm_pagefree(pg); 222 } 223 /* Flush updates through and flush the TLB */ 224 xpq_queue_tlb_flush(); 225 xpq_flush_queue(); 226 splx(s); 227 return error; 228 } 229 230 231 /* 232 * Allocate physical memory from the given physical address range. 233 * Called by DMA-safe memory allocation methods. 234 * We need our own version to deal with physical vs machine addresses. 235 */ 236 int 237 _xen_bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, 238 bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, 239 int nsegs, int *rsegs, int flags, bus_addr_t low, bus_addr_t high) 240 { 241 bus_addr_t curaddr, lastaddr; 242 struct vm_page *m; 243 struct pglist mlist; 244 int curseg, error; 245 int doingrealloc = 0; 246 247 /* Always round the size. */ 248 size = round_page(size); 249 250 KASSERT((alignment & (alignment - 1)) == 0); 251 KASSERT((boundary & (boundary - 1)) == 0); 252 if (alignment < PAGE_SIZE) 253 alignment = PAGE_SIZE; 254 if (boundary != 0 && boundary < size) 255 return (EINVAL); 256 257 /* 258 * Allocate pages from the VM system. 259 */ 260 error = uvm_pglistalloc(size, 0, avail_end, alignment, boundary, 261 &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0); 262 if (error) 263 return (error); 264 again: 265 266 /* 267 * Compute the location, size, and number of segments actually 268 * returned by the VM code. 269 */ 270 m = mlist.tqh_first; 271 curseg = 0; 272 curaddr = lastaddr = segs[curseg].ds_addr = _BUS_VM_PAGE_TO_BUS(m); 273 if (curaddr < low || curaddr >= high) 274 goto badaddr; 275 segs[curseg].ds_len = PAGE_SIZE; 276 m = m->pageq.queue.tqe_next; 277 if ((segs[curseg].ds_addr & (alignment - 1)) != 0) 278 goto dorealloc; 279 280 for (; m != NULL; m = m->pageq.queue.tqe_next) { 281 curaddr = _BUS_VM_PAGE_TO_BUS(m); 282 if (curaddr < low || curaddr >= high) 283 goto badaddr; 284 if (curaddr == (lastaddr + PAGE_SIZE)) { 285 segs[curseg].ds_len += PAGE_SIZE; 286 if ((lastaddr & boundary) != (curaddr & boundary)) 287 goto dorealloc; 288 } else { 289 curseg++; 290 if (curseg >= nsegs || (curaddr & (alignment - 1)) != 0) 291 goto dorealloc; 292 segs[curseg].ds_addr = curaddr; 293 segs[curseg].ds_len = PAGE_SIZE; 294 } 295 lastaddr = curaddr; 296 } 297 298 *rsegs = curseg + 1; 299 return (0); 300 301 badaddr: 302 #ifdef XEN3 303 if (doingrealloc == 0) 304 goto dorealloc; 305 if (curaddr < low) { 306 /* no way to enforce this */ 307 printf("_xen_bus_dmamem_alloc_range: no way to " 308 "enforce address range\n"); 309 uvm_pglistfree(&mlist); 310 return EINVAL; 311 } 312 printf("xen_bus_dmamem_alloc_range: " 313 "curraddr=0x%lx > high=0x%lx\n", 314 (u_long)curaddr, (u_long)high); 315 panic("xen_bus_dmamem_alloc_range 1"); 316 #else /* !XEN3 */ 317 /* 318 * If machine addresses are outside the allowed 319 * range we have to bail. Xen2 doesn't offer an 320 * interface to get memory in a specific address 321 * range. 322 */ 323 printf("_xen_bus_dmamem_alloc_range: no way to " 324 "enforce address range\n"); 325 uvm_pglistfree(&mlist); 326 return EINVAL; 327 #endif /* XEN3 */ 328 dorealloc: 329 if (doingrealloc == 1) 330 panic("_xen_bus_dmamem_alloc_range: " 331 "xen_alloc_contig returned " 332 "too much segments"); 333 doingrealloc = 1; 334 /* 335 * Too much segments, or memory doesn't fit 336 * constraints. Free this memory and 337 * get a contigous segment from the hypervisor. 338 */ 339 uvm_pglistfree(&mlist); 340 for (curseg = 0; curseg < nsegs; curseg++) { 341 segs[curseg].ds_addr = 0; 342 segs[curseg].ds_len = 0; 343 } 344 error = _xen_alloc_contig(size, alignment, 345 boundary, &mlist, flags, low, high); 346 if (error) 347 return error; 348 goto again; 349 } 350
Indexes created Sat Oct 18 17:09:52 GMT 2025