Re: [Qemu-devel] [PATCH] v6 revamp acpitable parsing and allow to specify complete (headerful) table

[John Baboval]

Thanks.

Somehow completely missed Blue's response back on the 15th. Glad to see this 
in.  

When using this for SLIC I had to patch the OEM ID fields in the other tables 
to match at runtime in order to make windows licensing happy. But thats a BIOS 
change, not something in QEMU....

On Jul 30, 2011, at 2:41 AM, "Blue Swirl" <address@hidden> wrote:

> Thanks, applied.
> 
> On Fri, Jul 29, 2011 at 4:49 AM, Isaku Yamahata <address@hidden> wrote:
>> On Fri, Jul 15, 2011 at 07:51:43PM +0300, Blue Swirl wrote:
>>> On Fri, Jul 15, 2011 at 6:18 PM, John Baboval
>>> <address@hidden> wrote:
>>>> Is there something I can do to help take this patch the rest of the way?
>>>> 
>>>> I'd hate to see it die because of a style issue and a compiler warning.
>>> 
>>> There's also suspicious missing 'break' statement. How about fixing
>>> the issues and submitting the patch?
>> 
>> I fixed the compile error.
>> I think the missing break is intentional, so added an comment there. Michael?
>> Blue, can you please take a look of it?
>> 
>> 
>> From 9a5e4158074ea251ab064a946927bcaf861f5c1e Mon Sep 17 00:00:00 2001
>> Message-Id: <address@hidden>
>> From: Michael Tokarev <address@hidden>
>> Date: Thu, 12 May 2011 18:44:17 +0400
>> Subject: [PATCH] revamp acpitable parsing and allow to specify complete 
>> (headerful) table
>> 
>> From Michael Tokarev <address@hidden>
>> 
>> This patch almost rewrites acpi_table_add() function
>> (but still leaves it using old get_param_value() interface).
>> The result is that it's now possible to specify whole table
>> (together with a header) in an external file, instead of just
>> data portion, with a new file= parameter, but at the same time
>> it's still possible to specify header fields as before.
>> 
>> Now with the checkpatch.pl formatting fixes, thanks to
>> Stefan Hajnoczi for suggestions, with changes from
>> Isaku Yamahata, and with my further refinements.
>> 
>> Signed-off-by: Michael Tokarev <address@hidden>
>> Cc:: Isaku Yamahata <address@hidden>
>> Cc: John Baboval <address@hidden>
>> Cc: Blue Swirl <address@hidden>
>> 
>> ---
>> v5: rediffed against current qemu/master.
>> v6: fix one "} else {" coding style defect (noted by Blue Swirl)
>> v7: style fix and added an comment for suspicious break
>>    I think that the missing break of case 0 is intentional.
>>    I added the fallthrough comment there.
>> ---
>>  hw/acpi.c       |  298 
>> ++++++++++++++++++++++++++++++++-----------------------
>>  qemu-options.hx |    7 +-
>>  2 files changed, 178 insertions(+), 127 deletions(-)
>> 
>> diff --git a/hw/acpi.c b/hw/acpi.c
>> index ad40fb4..79ec66c 100644
>> --- a/hw/acpi.c
>> +++ b/hw/acpi.c
>> @@ -20,19 +20,30 @@
>>  #include "pc.h"
>>  #include "acpi.h"
>> 
>> -struct acpi_table_header
>> -{
>> -    char signature [4];    /* ACPI signature (4 ASCII characters) */
>> +struct acpi_table_header {
>> +    uint16_t _length;         /* our length, not actual part of the hdr */
>> +                              /* XXX why we have 2 length fields here? */
>> +    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 # */
>>     uint8_t checksum;         /* To make sum of entire table == 0 */
>> -    char oem_id [6];       /* OEM identification */
>> -    char oem_table_id [8]; /* OEM table identification */
>> +    char oem_id[6];           /* OEM identification */
>> +    char oem_table_id[8];     /* OEM table identification */
>>     uint32_t oem_revision;    /* OEM revision number */
>> -    char asl_compiler_id [4]; /* ASL compiler vendor ID */
>> +    char asl_compiler_id[4];  /* ASL compiler vendor ID */
>>     uint32_t asl_compiler_revision; /* ASL compiler revision number */
>>  } __attribute__((packed));
>> 
>> +#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 dfl_hdr[ACPI_TABLE_HDR_SIZE] =
>> +    "\0\0"                   /* fake _length (2) */
>> +    "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) */
>> +    ;
>> +
>>  char *acpi_tables;
>>  size_t acpi_tables_len;
>> 
>> @@ -40,163 +51,198 @@ static int acpi_checksum(const uint8_t *data, int len)
>>  {
>>     int sum, i;
>>     sum = 0;
>> -    for(i = 0; i < len; i++)
>> +    for (i = 0; i < len; i++) {
>>         sum += data[i];
>> +    }
>>     return (-sum) & 0xff;
>>  }
>> 
>> +/* like strncpy() but zero-fills the tail of destination */
>> +static void strzcpy(char *dst, const char *src, size_t size)
>> +{
>> +    size_t len = strlen(src);
>> +    if (len >= size) {
>> +        len = size;
>> +    } else {
>> +      memset(dst + len, 0, size - len);
>> +    }
>> +    memcpy(dst, src, len);
>> +}
>> +
>> +/* XXX fixme: this function uses obsolete argument parsing interface */
>>  int acpi_table_add(const char *t)
>>  {
>> -    static const char *dfl_id = "QEMUQEMU";
>>     char buf[1024], *p, *f;
>> -    struct acpi_table_header acpi_hdr;
>>     unsigned long val;
>> -    uint32_t length;
>> -    struct acpi_table_header *acpi_hdr_p;
>> -    size_t off;
>> +    size_t len, start, allen;
>> +    bool has_header;
>> +    int changed;
>> +    int r;
>> +    struct acpi_table_header hdr;
>> +
>> +    r = 0;
>> +    r |= get_param_value(buf, sizeof(buf), "data", t) ? 1 : 0;
>> +    r |= get_param_value(buf, sizeof(buf), "file", t) ? 2 : 0;
>> +    switch (r) {
>> +    case 0:
>> +        buf[0] = '\0';
>> +        /* fallthrough for default behavior */
>> +    case 1:
>> +        has_header = false;
>> +        break;
>> +    case 2:
>> +        has_header = true;
>> +        break;
>> +    default:
>> +        fprintf(stderr, "acpitable: both data and file are specified\n");
>> +        return -1;
>> +    }
>> 
>> -    memset(&acpi_hdr, 0, sizeof(acpi_hdr));
>> -
>> -    if (get_param_value(buf, sizeof(buf), "sig", t)) {
>> -        strncpy(acpi_hdr.signature, buf, 4);
>> +    if (!acpi_tables) {
>> +        allen = sizeof(uint16_t);
>> +        acpi_tables = qemu_mallocz(allen);
>>     } else {
>> -        strncpy(acpi_hdr.signature, dfl_id, 4);
>> +        allen = acpi_tables_len;
>>     }
>> +
>> +    start = allen;
>> +    acpi_tables = qemu_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 (f = strtok(buf, ":"); f; f = strtok(NULL, ":")) {
>> +        int fd = open(f, O_RDONLY);
>> +
>> +        if (fd < 0) {
>> +            fprintf(stderr, "can't open file %s: %s\n", f, strerror(errno));
>> +            return -1;
>> +        }
>> +
>> +        for (;;) {
>> +            char data[8192];
>> +            r = read(fd, data, sizeof(data));
>> +            if (r == 0) {
>> +                break;
>> +            } else if (r > 0) {
>> +                acpi_tables = qemu_realloc(acpi_tables, allen + r);
>> +                memcpy(acpi_tables + allen, data, r);
>> +                allen += r;
>> +            } else if (errno != EINTR) {
>> +                fprintf(stderr, "can't read file %s: %s\n",
>> +                        f, strerror(errno));
>> +                close(fd);
>> +                return -1;
>> +            }
>> +        }
>> +
>> +        close(fd);
>> +    }
>> +
>> +    /* now fill in the header fields */
>> +
>> +    f = acpi_tables + start;   /* start of the table */
>> +    changed = 0;
>> +
>> +    /* copy the header to temp place to align the fields */
>> +    memcpy(&hdr, has_header ? f : 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 (get_param_value(buf, sizeof(buf), "sig", t)) {
>> +        strzcpy(hdr.sig, buf, sizeof(hdr.sig));
>> +        ++changed;
>> +    }
>> +
>> +    /* length of the table including header, in bytes */
>> +    if (has_header) {
>> +        /* 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 (get_param_value(buf, sizeof(buf), "rev", t)) {
>> -        val = strtoul(buf, &p, 10);
>> -        if (val > 255 || *p != '\0')
>> -            goto out;
>> -    } else {
>> -        val = 1;
>> +        val = strtoul(buf, &p, 0);
>> +        if (val > 255 || *p) {
>> +            fprintf(stderr, "acpitable: \"rev=%s\" is invalid\n", buf);
>> +            return -1;
>> +        }
>> +        hdr.revision = (uint8_t)val;
>> +        ++changed;
>>     }
>> -    acpi_hdr.revision = (int8_t)val;
>> 
>>     if (get_param_value(buf, sizeof(buf), "oem_id", t)) {
>> -        strncpy(acpi_hdr.oem_id, buf, 6);
>> -    } else {
>> -        strncpy(acpi_hdr.oem_id, dfl_id, 6);
>> +        strzcpy(hdr.oem_id, buf, sizeof(hdr.oem_id));
>> +        ++changed;
>>     }
>> 
>>     if (get_param_value(buf, sizeof(buf), "oem_table_id", t)) {
>> -        strncpy(acpi_hdr.oem_table_id, buf, 8);
>> -    } else {
>> -        strncpy(acpi_hdr.oem_table_id, dfl_id, 8);
>> +        strzcpy(hdr.oem_table_id, buf, sizeof(hdr.oem_table_id));
>> +        ++changed;
>>     }
>> 
>>     if (get_param_value(buf, sizeof(buf), "oem_rev", t)) {
>> -        val = strtol(buf, &p, 10);
>> -        if(*p != '\0')
>> -            goto out;
>> -    } else {
>> -        val = 1;
>> +        val = strtol(buf, &p, 0);
>> +        if (*p) {
>> +            fprintf(stderr, "acpitable: \"oem_rev=%s\" is invalid\n", buf);
>> +            return -1;
>> +        }
>> +        hdr.oem_revision = cpu_to_le32(val);
>> +        ++changed;
>>     }
>> -    acpi_hdr.oem_revision = cpu_to_le32(val);
>> 
>>     if (get_param_value(buf, sizeof(buf), "asl_compiler_id", t)) {
>> -        strncpy(acpi_hdr.asl_compiler_id, buf, 4);
>> -    } else {
>> -        strncpy(acpi_hdr.asl_compiler_id, dfl_id, 4);
>> +        strzcpy(hdr.asl_compiler_id, buf, sizeof(hdr.asl_compiler_id));
>> +        ++changed;
>>     }
>> 
>>     if (get_param_value(buf, sizeof(buf), "asl_compiler_rev", t)) {
>> -        val = strtol(buf, &p, 10);
>> -        if(*p != '\0')
>> -            goto out;
>> -    } else {
>> -        val = 1;
>> -    }
>> -    acpi_hdr.asl_compiler_revision = cpu_to_le32(val);
>> -
>> -    if (!get_param_value(buf, sizeof(buf), "data", t)) {
>> -         buf[0] = '\0';
>> -    }
>> -
>> -    length = sizeof(acpi_hdr);
>> -
>> -    f = buf;
>> -    while (buf[0]) {
>> -        struct stat s;
>> -        char *n = strchr(f, ':');
>> -        if (n)
>> -            *n = '\0';
>> -        if(stat(f, &s) < 0) {
>> -            fprintf(stderr, "Can't stat file '%s': %s\n", f, 
>> strerror(errno));
>> -            goto out;
>> +        val = strtol(buf, &p, 0);
>> +        if (*p) {
>> +            fprintf(stderr, "acpitable: \"%s=%s\" is invalid\n",
>> +                    "asl_compiler_rev", buf);
>> +            return -1;
>>         }
>> -        length += s.st_size;
>> -        if (!n)
>> -            break;
>> -        *n = ':';
>> -        f = n + 1;
>> +        hdr.asl_compiler_revision = cpu_to_le32(val);
>> +        ++changed;
>>     }
>> 
>> -    if (!acpi_tables) {
>> -        acpi_tables_len = sizeof(uint16_t);
>> -        acpi_tables = qemu_mallocz(acpi_tables_len);
>> +    if (!has_header && !changed) {
>> +        fprintf(stderr, "warning: acpitable: no table headers are 
>> specified\n");
>>     }
>> -    acpi_tables = qemu_realloc(acpi_tables,
>> -                               acpi_tables_len + sizeof(uint16_t) + length);
>> -    p = acpi_tables + acpi_tables_len;
>> -    acpi_tables_len += sizeof(uint16_t) + length;
>> -
>> -    *(uint16_t*)p = cpu_to_le32(length);
>> -    p += sizeof(uint16_t);
>> -    memcpy(p, &acpi_hdr, sizeof(acpi_hdr));
>> -    off = sizeof(acpi_hdr);
>> -
>> -    f = buf;
>> -    while (buf[0]) {
>> -        struct stat s;
>> -        int fd;
>> -        char *n = strchr(f, ':');
>> -        if (n)
>> -            *n = '\0';
>> -        fd = open(f, O_RDONLY);
>> -
>> -        if(fd < 0)
>> -            goto out;
>> -        if(fstat(fd, &s) < 0) {
>> -            close(fd);
>> -            goto out;
>> -        }
>> 
>> -        /* off < length is necessary because file size can be changed
>> -           under our foot */
>> -        while(s.st_size && off < length) {
>> -            int r;
>> -            r = read(fd, p + off, s.st_size);
>> -            if (r > 0) {
>> -                off += r;
>> -                s.st_size -= r;
>> -            } else if ((r < 0 && errno != EINTR) || r == 0) {
>> -                close(fd);
>> -                goto out;
>> -            }
>> -        }
>> 
>> -        close(fd);
>> -        if (!n)
>> -            break;
>> -        f = n + 1;
>> -    }
>> -    if (off < length) {
>> -        /* don't pass random value in process to guest */
>> -        memset(p + off, 0, length - off);
>> +    /* 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(f, &hdr, sizeof(hdr));
>> +
>> +    if (changed || !has_header || 1) {
>> +        ((struct acpi_table_header *)f)->checksum =
>> +            acpi_checksum((uint8_t *)f + ACPI_TABLE_PFX_SIZE, len);
>>     }
>> 
>> -    acpi_hdr_p = (struct acpi_table_header*)p;
>> -    acpi_hdr_p->length = cpu_to_le32(length);
>> -    acpi_hdr_p->checksum = acpi_checksum((uint8_t*)p, length);
>>     /* increase number of tables */
>> -    (*(uint16_t*)acpi_tables) =
>> -           cpu_to_le32(le32_to_cpu(*(uint16_t*)acpi_tables) + 1);
>> +    (*(uint16_t *)acpi_tables) =
>> +        cpu_to_le32(le32_to_cpu(*(uint16_t *)acpi_tables) + 1);
>> +
>> +    acpi_tables_len = allen;
>>     return 0;
>> -out:
>> -    if (acpi_tables) {
>> -        qemu_free(acpi_tables);
>> -        acpi_tables = NULL;
>> -    }
>> -    return -1;
>> +
>>  }
>> 
>>  /* ACPI PM1a EVT */
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 1d57f64..74c0edb 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -1062,12 +1062,17 @@ Enable virtio balloon device (default), optionally 
>> with PCI address
>>  ETEXI
>> 
>>  DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
>> -    "-acpitable 
>> [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,data=file1[:file2]...]\n"
>> +    "-acpitable 
>> [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n"
>>     "                ACPI table description\n", QEMU_ARCH_I386)
>>  STEXI
>>  @item -acpitable 
>> address@hidden,address@hidden,address@hidden,address@hidden,address@hidden 
>> [,address@hidden,address@hidden,address@hidden:@var{file2}]...]
>>  @findex -acpitable
>>  Add ACPI table with specified header fields and context from specified 
>> files.
>> +For file=, take whole ACPI table from the specified files, including all
>> +ACPI headers (possible overridden by other options).
>> +For data=, only data
>> +portion of the table is used, all header information is specified in the
>> +command line.
>>  ETEXI
>> 
>>  DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
>> --
>> 1.7.1.1
>> 
>> 
>> 
>> --
>> yamahata
>>