Commit 2b45c3f5 authored by Richard Henderson's avatar Richard Henderson
Browse files

qemu/osdep: Remove the need for qemu_init_auxval 



Instead of getting backup auxv data from the env pointer given to main,
read it from /proc/self/auxv.  We can do this at any time, so we're not
tied to any ordering wrt a call to qemu_init_auxval from main.

Tested-by: default avatarTom Musta <tommusta@gmail.com>
Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent 40d964b5

include/qemu/osdep.h

+0 −12
Original line number Diff line number Diff line
@@ -251,18 +251,6 @@ unsigned long qemu_getauxval(unsigned long type); 
static inline unsigned long qemu_getauxval(unsigned long type) { return 0; }

#endif



/**

 * qemu_init_auxval:

 * @envp: the third argument to main

 *

 * If supported and required, locate the auxiliary vector at program startup.

 */

#if defined(CONFIG_GETAUXVAL) || !defined(__linux__)

static inline void qemu_init_auxval(char **envp) { }

#else

void qemu_init_auxval(char **envp);

#endif



void qemu_set_tty_echo(int fd, bool echo);



void os_mem_prealloc(int fd, char *area, size_t sz);

linux-user/main.c

+0 −1
Original line number Diff line number Diff line
@@ -3829,7 +3829,6 @@ int main(int argc, char **argv, char **envp) 


    module_call_init(MODULE_INIT_QOM);



    qemu_init_auxval(envp);

    qemu_cache_utils_init();



    if ((envlist = envlist_create()) == NULL) {

util/getauxval.c

+39 −12
Original line number Diff line number Diff line
@@ -48,26 +48,53 @@ typedef struct { 


static const ElfW_auxv_t *auxv;



void qemu_init_auxval(char **envp)

static const ElfW_auxv_t *qemu_init_auxval(void)

{

    /* The auxiliary vector is located just beyond the initial environment.  */

    while (*envp++ != NULL) {

        continue;

    ElfW_auxv_t *a;

    ssize_t size = 512, r, ofs;

    int fd;



    /* Allocate some initial storage.  Make sure the first entry is set

       to end-of-list, so that we've got a valid list in case of error.  */

    auxv = a = g_malloc(size);

    a[0].a_type = 0;

    a[0].a_val = 0;



    fd = open("/proc/self/auxv", O_RDONLY);

    if (fd < 0) {

        return a;

    }



    /* Read the first SIZE bytes.  Hopefully, this covers everything.  */

    r = read(fd, a, size);



    if (r == size) {

        /* Continue to expand until we do get a partial read.  */

        do {

            ofs = size;

            size *= 2;

            auxv = a = g_realloc(a, size);

            r = read(fd, (char *)a + ofs, ofs);

        } while (r == ofs);

    }

    auxv = (const ElfW_auxv_t *)envp;



    close(fd);

    return a;

}



unsigned long qemu_getauxval(unsigned long type)

{

    /* If we were able to find the auxiliary vector, use it.  */

    if (auxv) {

        const ElfW_auxv_t *a;

        for (a = auxv; a->a_type != 0; a++) {

    const ElfW_auxv_t *a = auxv;



    if (unlikely(a == NULL)) {

        a = qemu_init_auxval();

    }



    for (; a->a_type != 0; a++) {

        if (a->a_type == type) {

            return a->a_val;

        }

    }

    }



    return 0;

}

vl.c

+0 −1
Original line number Diff line number Diff line
@@ -2974,7 +2974,6 @@ int main(int argc, char **argv, char **envp) 


    rtc_clock = QEMU_CLOCK_HOST;



    qemu_init_auxval(envp);

    qemu_cache_utils_init();



    QLIST_INIT (&vm_change_state_head);