| 1 | /* |
| 2 | * QEMU SPAPR Architecture Option Vector Helper Functions |
| 3 | * |
| 4 | * Copyright IBM Corp. 2016 |
| 5 | * |
| 6 | * Authors: |
| 7 | * Bharata B Rao <bharata@linux.vnet.ibm.com> |
| 8 | * Michael Roth <mdroth@linux.vnet.ibm.com> |
| 9 | * |
| 10 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 11 | * See the COPYING file in the top-level directory. |
| 12 | */ |
| 13 | |
| 14 | #include "qemu/osdep.h" |
| 15 | #include "hw/ppc/spapr_ovec.h" |
| 16 | #include "migration/vmstate.h" |
| 17 | #include "qemu/bitmap.h" |
| 18 | #include "system/address-spaces.h" |
| 19 | #include "system/memory.h" |
| 20 | #include "qemu/error-report.h" |
| 21 | #include "trace.h" |
| 22 | #include <libfdt.h> |
| 23 | |
| 24 | #define OV_MAXBYTES 256 /* not including length byte */ |
| 25 | #define OV_MAXBITS (OV_MAXBYTES * BITS_PER_BYTE) |
| 26 | |
| 27 | /* we *could* work with bitmaps directly, but handling the bitmap privately |
| 28 | * allows us to more safely make assumptions about the bitmap size and |
| 29 | * simplify the calling code somewhat |
| 30 | */ |
| 31 | struct SpaprOptionVector { |
| 32 | unsigned long *bitmap; |
| 33 | int32_t bitmap_size; /* only used for migration */ |
| 34 | }; |
| 35 | |
| 36 | const VMStateDescription vmstate_spapr_ovec = { |
| 37 | .name = "spapr_option_vector", |
| 38 | .version_id = 1, |
| 39 | .minimum_version_id = 1, |
| 40 | .fields = (const VMStateField[]) { |
| 41 | VMSTATE_BITMAP(bitmap, SpaprOptionVector, 1, bitmap_size), |
| 42 | VMSTATE_END_OF_LIST() |
| 43 | } |
| 44 | }; |
| 45 | |
| 46 | SpaprOptionVector *spapr_ovec_new(void) |
| 47 | { |
| 48 | SpaprOptionVector *ov; |
| 49 | |
| 50 | ov = g_new0(SpaprOptionVector, 1); |
| 51 | ov->bitmap = bitmap_new(OV_MAXBITS); |
| 52 | ov->bitmap_size = OV_MAXBITS; |
| 53 | |
| 54 | return ov; |
| 55 | } |
| 56 | |
| 57 | SpaprOptionVector *spapr_ovec_clone(SpaprOptionVector *ov_orig) |
| 58 | { |
| 59 | SpaprOptionVector *ov; |
| 60 | |
| 61 | g_assert(ov_orig); |
| 62 | |
| 63 | ov = spapr_ovec_new(); |
| 64 | bitmap_copy(ov->bitmap, ov_orig->bitmap, OV_MAXBITS); |
| 65 | |
| 66 | return ov; |
| 67 | } |
| 68 | |
| 69 | void spapr_ovec_intersect(SpaprOptionVector *ov, |
| 70 | SpaprOptionVector *ov1, |
| 71 | SpaprOptionVector *ov2) |
| 72 | { |
| 73 | g_assert(ov); |
| 74 | g_assert(ov1); |
| 75 | g_assert(ov2); |
| 76 | |
| 77 | bitmap_and(ov->bitmap, ov1->bitmap, ov2->bitmap, OV_MAXBITS); |
| 78 | } |
| 79 | |
| 80 | /* returns true if ov1 has a subset of bits in ov2 */ |
| 81 | bool spapr_ovec_subset(SpaprOptionVector *ov1, SpaprOptionVector *ov2) |
| 82 | { |
| 83 | unsigned long *tmp = bitmap_new(OV_MAXBITS); |
| 84 | bool result; |
| 85 | |
| 86 | g_assert(ov1); |
| 87 | g_assert(ov2); |
| 88 | |
| 89 | bitmap_andnot(tmp, ov1->bitmap, ov2->bitmap, OV_MAXBITS); |
| 90 | result = bitmap_empty(tmp, OV_MAXBITS); |
| 91 | |
| 92 | g_free(tmp); |
| 93 | |
| 94 | return result; |
| 95 | } |
| 96 | |
| 97 | void spapr_ovec_cleanup(SpaprOptionVector *ov) |
| 98 | { |
| 99 | if (ov) { |
| 100 | g_free(ov->bitmap); |
| 101 | g_free(ov); |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | void spapr_ovec_set(SpaprOptionVector *ov, long bitnr) |
| 106 | { |
| 107 | g_assert(ov); |
| 108 | g_assert(bitnr < OV_MAXBITS); |
| 109 | |
| 110 | set_bit(bitnr, ov->bitmap); |
| 111 | } |
| 112 | |
| 113 | void spapr_ovec_clear(SpaprOptionVector *ov, long bitnr) |
| 114 | { |
| 115 | g_assert(ov); |
| 116 | g_assert(bitnr < OV_MAXBITS); |
| 117 | |
| 118 | clear_bit(bitnr, ov->bitmap); |
| 119 | } |
| 120 | |
| 121 | bool spapr_ovec_test(SpaprOptionVector *ov, long bitnr) |
| 122 | { |
| 123 | g_assert(ov); |
| 124 | g_assert(bitnr < OV_MAXBITS); |
| 125 | |
| 126 | return test_bit(bitnr, ov->bitmap) ? true : false; |
| 127 | } |
| 128 | |
| 129 | bool spapr_ovec_empty(SpaprOptionVector *ov) |
| 130 | { |
| 131 | g_assert(ov); |
| 132 | |
| 133 | return bitmap_empty(ov->bitmap, OV_MAXBITS); |
| 134 | } |
| 135 | |
| 136 | static void guest_byte_to_bitmap(uint8_t entry, unsigned long *bitmap, |
| 137 | long bitmap_offset) |
| 138 | { |
| 139 | int i; |
| 140 | |
| 141 | for (i = 0; i < BITS_PER_BYTE; i++) { |
| 142 | if (entry & (1 << (BITS_PER_BYTE - 1 - i))) { |
| 143 | bitmap_set(bitmap, bitmap_offset + i, 1); |
| 144 | } |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | static uint8_t guest_byte_from_bitmap(unsigned long *bitmap, long bitmap_offset) |
| 149 | { |
| 150 | uint8_t entry = 0; |
| 151 | int i; |
| 152 | |
| 153 | for (i = 0; i < BITS_PER_BYTE; i++) { |
| 154 | if (test_bit(bitmap_offset + i, bitmap)) { |
| 155 | entry |= (1 << (BITS_PER_BYTE - 1 - i)); |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | return entry; |
| 160 | } |
| 161 | |
| 162 | static target_ulong vector_addr(target_ulong table_addr, int vector) |
| 163 | { |
| 164 | uint16_t vector_count, vector_len; |
| 165 | int i; |
| 166 | |
| 167 | vector_count = ldub_phys(&address_space_memory, table_addr) + 1; |
| 168 | if (vector > vector_count) { |
| 169 | return 0; |
| 170 | } |
| 171 | table_addr++; /* skip nr option vectors */ |
| 172 | |
| 173 | for (i = 0; i < vector - 1; i++) { |
| 174 | vector_len = ldub_phys(&address_space_memory, table_addr) + 1; |
| 175 | table_addr += vector_len + 1; /* bit-vector + length byte */ |
| 176 | } |
| 177 | return table_addr; |
| 178 | } |
| 179 | |
| 180 | SpaprOptionVector *spapr_ovec_parse_vector(target_ulong table_addr, int vector) |
| 181 | { |
| 182 | SpaprOptionVector *ov; |
| 183 | target_ulong addr; |
| 184 | uint16_t vector_len; |
| 185 | int i; |
| 186 | |
| 187 | g_assert(table_addr); |
| 188 | g_assert(vector >= 1); /* vector numbering starts at 1 */ |
| 189 | |
| 190 | addr = vector_addr(table_addr, vector); |
| 191 | if (!addr) { |
| 192 | /* specified vector isn't present */ |
| 193 | return NULL; |
| 194 | } |
| 195 | |
| 196 | vector_len = ldub_phys(&address_space_memory, addr++) + 1; |
| 197 | g_assert(vector_len <= OV_MAXBYTES); |
| 198 | ov = spapr_ovec_new(); |
| 199 | |
| 200 | for (i = 0; i < vector_len; i++) { |
| 201 | uint8_t entry = ldub_phys(&address_space_memory, addr + i); |
| 202 | if (entry) { |
| 203 | trace_spapr_ovec_parse_vector(vector, i + 1, vector_len, entry); |
| 204 | guest_byte_to_bitmap(entry, ov->bitmap, i * BITS_PER_BYTE); |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | return ov; |
| 209 | } |
| 210 | |
| 211 | int spapr_dt_ovec(void *fdt, int fdt_offset, |
| 212 | SpaprOptionVector *ov, const char *name) |
| 213 | { |
| 214 | uint8_t vec[OV_MAXBYTES + 1]; |
| 215 | uint16_t vec_len; |
| 216 | unsigned long lastbit; |
| 217 | int i; |
| 218 | |
| 219 | g_assert(ov); |
| 220 | |
| 221 | lastbit = find_last_bit(ov->bitmap, OV_MAXBITS); |
| 222 | /* if no bits are set, include at least 1 byte of the vector so we can |
| 223 | * still encoded this in the device tree while abiding by the same |
| 224 | * encoding/sizing expected in ibm,client-architecture-support |
| 225 | */ |
| 226 | vec_len = (lastbit == OV_MAXBITS) ? 1 : lastbit / BITS_PER_BYTE + 1; |
| 227 | g_assert(vec_len <= OV_MAXBYTES); |
| 228 | /* guest expects vector len encoded as vec_len - 1, since the length byte |
| 229 | * is assumed and not included, and the first byte of the vector |
| 230 | * is assumed as well |
| 231 | */ |
| 232 | vec[0] = vec_len - 1; |
| 233 | |
| 234 | for (i = 1; i < vec_len + 1; i++) { |
| 235 | vec[i] = guest_byte_from_bitmap(ov->bitmap, (i - 1) * BITS_PER_BYTE); |
| 236 | if (vec[i]) { |
| 237 | trace_spapr_ovec_populate_dt(i, vec_len, vec[i]); |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | return fdt_setprop(fdt, fdt_offset, name, vec, vec_len + 1); |
| 242 | } |