1 /* 2 * Copyright © 2018, 2021 Oracle and/or its affiliates. 3 * 4 * This work is licensed under the terms of the GNU GPL, version 2 or later. 5 * See the COPYING file in the top-level directory. 6 * 7 */ 8 9 #include "qemu/osdep.h" 10 11 #include "qemu/int128.h" 12 #include "qemu/range.h" 13 #include "exec/memory.h" 14 #include "exec/cpu-common.h" 15 #include "exec/ram_addr.h" 16 #include "qapi/error.h" 17 #include "qemu/error-report.h" 18 #include "hw/remote/mpqemu-link.h" 19 #include "hw/remote/proxy-memory-listener.h" 20 21 /* 22 * TODO: get_fd_from_hostaddr(), proxy_mrs_can_merge() and 23 * proxy_memory_listener_commit() defined below perform tasks similar to the 24 * functions defined in vhost-user.c. These functions are good candidates 25 * for refactoring. 26 * 27 */ 28 29 static void proxy_memory_listener_reset(MemoryListener *listener) 30 { 31 ProxyMemoryListener *proxy_listener = container_of(listener, 32 ProxyMemoryListener, 33 listener); 34 int mrs; 35 36 for (mrs = 0; mrs < proxy_listener->n_mr_sections; mrs++) { 37 memory_region_unref(proxy_listener->mr_sections[mrs].mr); 38 } 39 40 g_free(proxy_listener->mr_sections); 41 proxy_listener->mr_sections = NULL; 42 proxy_listener->n_mr_sections = 0; 43 } 44 45 static int get_fd_from_hostaddr(uint64_t host, ram_addr_t *offset) 46 { 47 MemoryRegion *mr; 48 ram_addr_t off; 49 50 /** 51 * Assumes that the host address is a valid address as it's 52 * coming from the MemoryListener system. In the case host 53 * address is not valid, the following call would return 54 * the default subregion of "system_memory" region, and 55 * not NULL. So it's not possible to check for NULL here. 56 */ 57 mr = memory_region_from_host((void *)(uintptr_t)host, &off); 58 59 if (offset) { 60 *offset = off; 61 } 62 63 return memory_region_get_fd(mr); 64 } 65 66 static bool proxy_mrs_can_merge(uint64_t host, uint64_t prev_host, size_t size) 67 { 68 if (((prev_host + size) != host)) { 69 return false; 70 } 71 72 if (get_fd_from_hostaddr(host, NULL) != 73 get_fd_from_hostaddr(prev_host, NULL)) { 74 return false; 75 } 76 77 return true; 78 } 79 80 static bool try_merge(ProxyMemoryListener *proxy_listener, 81 MemoryRegionSection *section) 82 { 83 uint64_t mrs_size, mrs_gpa, mrs_page; 84 MemoryRegionSection *prev_sec; 85 bool merged = false; 86 uintptr_t mrs_host; 87 RAMBlock *mrs_rb; 88 89 if (!proxy_listener->n_mr_sections) { 90 return false; 91 } 92 93 mrs_rb = section->mr->ram_block; 94 mrs_page = (uint64_t)qemu_ram_pagesize(mrs_rb); 95 mrs_size = int128_get64(section->size); 96 mrs_gpa = section->offset_within_address_space; 97 mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 98 section->offset_within_region; 99 100 if (get_fd_from_hostaddr(mrs_host, NULL) < 0) { 101 return true; 102 } 103 104 mrs_host = mrs_host & ~(mrs_page - 1); 105 mrs_gpa = mrs_gpa & ~(mrs_page - 1); 106 mrs_size = ROUND_UP(mrs_size, mrs_page); 107 108 prev_sec = proxy_listener->mr_sections + 109 (proxy_listener->n_mr_sections - 1); 110 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 111 uint64_t prev_size = int128_get64(prev_sec->size); 112 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 113 uint64_t prev_host_start = 114 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 115 prev_sec->offset_within_region; 116 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 117 118 if (mrs_gpa <= (prev_gpa_end + 1)) { 119 g_assert(mrs_gpa > prev_gpa_start); 120 121 if ((section->mr == prev_sec->mr) && 122 proxy_mrs_can_merge(mrs_host, prev_host_start, 123 (mrs_gpa - prev_gpa_start))) { 124 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 125 merged = true; 126 prev_sec->offset_within_address_space = 127 MIN(prev_gpa_start, mrs_gpa); 128 prev_sec->offset_within_region = 129 MIN(prev_host_start, mrs_host) - 130 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 131 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 132 mrs_host)); 133 } 134 } 135 136 return merged; 137 } 138 139 static void proxy_memory_listener_region_addnop(MemoryListener *listener, 140 MemoryRegionSection *section) 141 { 142 ProxyMemoryListener *proxy_listener = container_of(listener, 143 ProxyMemoryListener, 144 listener); 145 146 if (!memory_region_is_ram(section->mr) || 147 memory_region_is_rom(section->mr)) { 148 return; 149 } 150 151 if (try_merge(proxy_listener, section)) { 152 return; 153 } 154 155 ++proxy_listener->n_mr_sections; 156 proxy_listener->mr_sections = g_renew(MemoryRegionSection, 157 proxy_listener->mr_sections, 158 proxy_listener->n_mr_sections); 159 proxy_listener->mr_sections[proxy_listener->n_mr_sections - 1] = *section; 160 proxy_listener->mr_sections[proxy_listener->n_mr_sections - 1].fv = NULL; 161 memory_region_ref(section->mr); 162 } 163 164 static void proxy_memory_listener_commit(MemoryListener *listener) 165 { 166 ProxyMemoryListener *proxy_listener = container_of(listener, 167 ProxyMemoryListener, 168 listener); 169 MPQemuMsg msg; 170 MemoryRegionSection *section; 171 ram_addr_t offset; 172 uintptr_t host_addr; 173 int region; 174 Error *local_err = NULL; 175 176 memset(&msg, 0, sizeof(MPQemuMsg)); 177 178 msg.cmd = MPQEMU_CMD_SYNC_SYSMEM; 179 msg.num_fds = proxy_listener->n_mr_sections; 180 msg.size = sizeof(SyncSysmemMsg); 181 if (msg.num_fds > REMOTE_MAX_FDS) { 182 error_report("Number of fds is more than %d", REMOTE_MAX_FDS); 183 return; 184 } 185 186 for (region = 0; region < proxy_listener->n_mr_sections; region++) { 187 section = &proxy_listener->mr_sections[region]; 188 msg.data.sync_sysmem.gpas[region] = 189 section->offset_within_address_space; 190 msg.data.sync_sysmem.sizes[region] = int128_get64(section->size); 191 host_addr = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 192 section->offset_within_region; 193 msg.fds[region] = get_fd_from_hostaddr(host_addr, &offset); 194 msg.data.sync_sysmem.offsets[region] = offset; 195 } 196 if (!mpqemu_msg_send(&msg, proxy_listener->ioc, &local_err)) { 197 error_report_err(local_err); 198 } 199 } 200 201 void proxy_memory_listener_deconfigure(ProxyMemoryListener *proxy_listener) 202 { 203 memory_listener_unregister(&proxy_listener->listener); 204 205 proxy_memory_listener_reset(&proxy_listener->listener); 206 } 207 208 void proxy_memory_listener_configure(ProxyMemoryListener *proxy_listener, 209 QIOChannel *ioc) 210 { 211 proxy_listener->n_mr_sections = 0; 212 proxy_listener->mr_sections = NULL; 213 214 proxy_listener->ioc = ioc; 215 216 proxy_listener->listener.begin = proxy_memory_listener_reset; 217 proxy_listener->listener.commit = proxy_memory_listener_commit; 218 proxy_listener->listener.region_add = proxy_memory_listener_region_addnop; 219 proxy_listener->listener.region_nop = proxy_memory_listener_region_addnop; 220 proxy_listener->listener.priority = MEMORY_LISTENER_PRIORITY_DEV_BACKEND; 221 proxy_listener->listener.name = "proxy"; 222 223 memory_listener_register(&proxy_listener->listener, 224 &address_space_memory); 225 } 226