diff options
Diffstat (limited to 'hw/acpi.c')
| -rw-r--r-- | hw/acpi.c | 284 |
1 files changed, 163 insertions, 121 deletions
@@ -30,7 +30,7 @@ struct acpi_table_header { uint16_t _length; /* our length, not actual part of the hdr */ - /* XXX why we have 2 length fields here? */ + /* allows easier parsing for fw_cfg clients */ char sig[4]; /* ACPI signature (4 ASCII characters) */ uint32_t length; /* Length of table, in bytes, including header */ uint8_t revision; /* ACPI Specification minor version # */ @@ -45,8 +45,7 @@ struct acpi_table_header { #define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header) #define ACPI_TABLE_PFX_SIZE sizeof(uint16_t) /* size of the extra prefix */ -static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE] = - "\0\0" /* fake _length (2) */ +static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] = "QEMU\0\0\0\0\1\0" /* sig (4), len(4), revno (1), csum (1) */ "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */ "QEMU\1\0\0\0" /* ASL compiler ID (4), version (4) */ @@ -79,19 +78,165 @@ static int acpi_checksum(const uint8_t *data, int len) return (-sum) & 0xff; } + +/* Install a copy of the ACPI table specified in @blob. + * + * If @has_header is set, @blob starts with the System Description Table Header + * structure. Otherwise, "dfl_hdr" is prepended. In any case, each header field + * is optionally overwritten from @hdrs. + * + * It is valid to call this function with + * (@blob == NULL && bloblen == 0 && !has_header). + * + * @hdrs->file and @hdrs->data are ignored. + * + * SIZE_MAX is considered "infinity" in this function. + * + * The number of tables that can be installed is not limited, but the 16-bit + * counter at the beginning of "acpi_tables" wraps around after UINT16_MAX. + */ +static void acpi_table_install(const char unsigned *blob, size_t bloblen, + bool has_header, + const struct AcpiTableOptions *hdrs, + Error **errp) +{ + size_t body_start; + const char unsigned *hdr_src; + size_t body_size, acpi_payload_size; + struct acpi_table_header *ext_hdr; + unsigned changed_fields; + + /* Calculate where the ACPI table body starts within the blob, plus where + * to copy the ACPI table header from. + */ + if (has_header) { + /* _length | ACPI header in blob | blob body + * ^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^ + * ACPI_TABLE_PFX_SIZE sizeof dfl_hdr body_size + * == body_start + * + * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + * acpi_payload_size == bloblen + */ + body_start = sizeof dfl_hdr; + + if (bloblen < body_start) { + error_setg(errp, "ACPI table claiming to have header is too " + "short, available: %zu, expected: %zu", bloblen, + body_start); + return; + } + hdr_src = blob; + } else { + /* _length | ACPI header in template | blob body + * ^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^ + * ACPI_TABLE_PFX_SIZE sizeof dfl_hdr body_size + * == bloblen + * + * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + * acpi_payload_size + */ + body_start = 0; + hdr_src = dfl_hdr; + } + body_size = bloblen - body_start; + acpi_payload_size = sizeof dfl_hdr + body_size; + + if (acpi_payload_size > UINT16_MAX) { + error_setg(errp, "ACPI table too big, requested: %zu, max: %u", + acpi_payload_size, (unsigned)UINT16_MAX); + return; + } + + /* We won't fail from here on. Initialize / extend the globals. */ + if (acpi_tables == NULL) { + acpi_tables_len = sizeof(uint16_t); + acpi_tables = g_malloc0(acpi_tables_len); + } + + acpi_tables = g_realloc(acpi_tables, acpi_tables_len + + ACPI_TABLE_PFX_SIZE + + sizeof dfl_hdr + body_size); + + ext_hdr = (struct acpi_table_header *)(acpi_tables + acpi_tables_len); + acpi_tables_len += ACPI_TABLE_PFX_SIZE; + + memcpy(acpi_tables + acpi_tables_len, hdr_src, sizeof dfl_hdr); + acpi_tables_len += sizeof dfl_hdr; + + if (blob != NULL) { + memcpy(acpi_tables + acpi_tables_len, blob + body_start, body_size); + acpi_tables_len += body_size; + } + + /* increase number of tables */ + cpu_to_le16wu((uint16_t *)acpi_tables, + le16_to_cpupu((uint16_t *)acpi_tables) + 1u); + + /* Update the header fields. The strings need not be NUL-terminated. */ + changed_fields = 0; + ext_hdr->_length = cpu_to_le16(acpi_payload_size); + + if (hdrs->has_sig) { + strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig); + ++changed_fields; + } + + if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) { + fprintf(stderr, + "warning: ACPI table has wrong length, header says " + "%" PRIu32 ", actual size %zu bytes\n", + le32_to_cpu(ext_hdr->length), acpi_payload_size); + } + ext_hdr->length = cpu_to_le32(acpi_payload_size); + + if (hdrs->has_rev) { + ext_hdr->revision = hdrs->rev; + ++changed_fields; + } + + ext_hdr->checksum = 0; + + if (hdrs->has_oem_id) { + strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id); + ++changed_fields; + } + if (hdrs->has_oem_table_id) { + strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id, + sizeof ext_hdr->oem_table_id); + ++changed_fields; + } + if (hdrs->has_oem_rev) { + ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev); + ++changed_fields; + } + if (hdrs->has_asl_compiler_id) { + strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id, + sizeof ext_hdr->asl_compiler_id); + ++changed_fields; + } + if (hdrs->has_asl_compiler_rev) { + ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev); + ++changed_fields; + } + + if (!has_header && changed_fields == 0) { + fprintf(stderr, "warning: ACPI table: no headers are specified\n"); + } + + /* recalculate checksum */ + ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr + + ACPI_TABLE_PFX_SIZE, acpi_payload_size); +} + int acpi_table_add(const QemuOpts *opts) { AcpiTableOptions *hdrs = NULL; Error *err = NULL; char **pathnames = NULL; char **cur; - - size_t len, start, allen; - bool has_header; - int changed; - int r; - struct acpi_table_header hdr; - char unsigned *table_start; + size_t bloblen = 0; + char unsigned *blob = NULL; { OptsVisitor *ov; @@ -108,7 +253,6 @@ int acpi_table_add(const QemuOpts *opts) error_setg(&err, "'-acpitable' requires one of 'data' or 'file'"); goto out; } - has_header = hdrs->has_file; pathnames = g_strsplit(hdrs->has_file ? hdrs->file : hdrs->data, ":", 0); if (pathnames == NULL || pathnames[0] == NULL) { @@ -116,19 +260,7 @@ int acpi_table_add(const QemuOpts *opts) goto out; } - if (!acpi_tables) { - allen = sizeof(uint16_t); - acpi_tables = g_malloc0(allen); - } else { - allen = acpi_tables_len; - } - - start = allen; - acpi_tables = g_realloc(acpi_tables, start + ACPI_TABLE_HDR_SIZE); - allen += has_header ? ACPI_TABLE_PFX_SIZE : ACPI_TABLE_HDR_SIZE; - /* now read in the data files, reallocating buffer as needed */ - for (cur = pathnames; *cur; ++cur) { int fd = open(*cur, O_RDONLY | O_BINARY); @@ -139,13 +271,15 @@ int acpi_table_add(const QemuOpts *opts) for (;;) { char unsigned data[8192]; - r = read(fd, data, sizeof(data)); + ssize_t r; + + r = read(fd, data, sizeof data); if (r == 0) { break; } else if (r > 0) { - acpi_tables = g_realloc(acpi_tables, allen + r); - memcpy(acpi_tables + allen, data, r); - allen += r; + blob = g_realloc(blob, bloblen + r); + memcpy(blob + bloblen, data, r); + bloblen += r; } else if (errno != EINTR) { error_setg(&err, "can't read file %s: %s", *cur, strerror(errno)); @@ -157,102 +291,10 @@ int acpi_table_add(const QemuOpts *opts) close(fd); } - /* now fill in the header fields */ - - table_start = acpi_tables + start; /* start of the table */ - changed = 0; - - /* copy the header to temp place to align the fields */ - memcpy(&hdr, has_header ? table_start : dfl_hdr, ACPI_TABLE_HDR_SIZE); - - /* length of the table minus our prefix */ - len = allen - start - ACPI_TABLE_PFX_SIZE; - - hdr._length = cpu_to_le16(len); - - if (hdrs->has_sig) { - /* strncpy is justified: the field need not be NUL-terminated. */ - strncpy(hdr.sig, hdrs->sig, sizeof(hdr.sig)); - ++changed; - } - - /* length of the table including header, in bytes */ - if (has_header) { - unsigned long val; - - /* check if actual length is correct */ - val = le32_to_cpu(hdr.length); - if (val != len) { - fprintf(stderr, - "warning: acpitable has wrong length," - " header says %lu, actual size %zu bytes\n", - val, len); - ++changed; - } - } - /* we may avoid putting length here if has_header is true */ - hdr.length = cpu_to_le32(len); - - if (hdrs->has_rev) { - hdr.revision = hdrs->rev; - ++changed; - } - - if (hdrs->has_oem_id) { - /* strncpy is justified: the field need not be NUL-terminated. */ - strncpy(hdr.oem_id, hdrs->oem_id, sizeof(hdr.oem_id)); - ++changed; - } - - if (hdrs->has_oem_table_id) { - /* strncpy is justified: the field need not be NUL-terminated. */ - strncpy(hdr.oem_table_id, hdrs->oem_table_id, - sizeof(hdr.oem_table_id)); - ++changed; - } - - if (hdrs->has_oem_rev) { - hdr.oem_revision = cpu_to_le32(hdrs->oem_rev); - ++changed; - } - - if (hdrs->has_asl_compiler_id) { - /* strncpy is justified: the field need not be NUL-terminated. */ - strncpy(hdr.asl_compiler_id, hdrs->asl_compiler_id, - sizeof(hdr.asl_compiler_id)); - ++changed; - } - - if (hdrs->has_asl_compiler_rev) { - hdr.asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev); - ++changed; - } - - if (!has_header && !changed) { - fprintf(stderr, "warning: acpitable: no table headers are specified\n"); - } - - - /* now calculate checksum of the table, complete with the header */ - /* we may as well leave checksum intact if has_header is true */ - /* alternatively there may be a way to set cksum to a given value */ - hdr.checksum = 0; /* for checksum calculation */ - - /* put header back */ - memcpy(table_start, &hdr, sizeof(hdr)); - - if (changed || !has_header || 1) { - ((struct acpi_table_header *)table_start)->checksum = - acpi_checksum((uint8_t *)table_start + ACPI_TABLE_PFX_SIZE, len); - } - - /* increase number of tables */ - (*(uint16_t *)acpi_tables) = - cpu_to_le32(le32_to_cpu(*(uint16_t *)acpi_tables) + 1); - - acpi_tables_len = allen; + acpi_table_install(blob, bloblen, hdrs->has_file, hdrs, &err); out: + g_free(blob); g_strfreev(pathnames); if (hdrs != NULL) { |