debuggers.hg

changeset 22892:52e928af3637

libxc: Do not use dom0 physmem as parameter to lzma decoder

It's not clear why a userspace lzma decode would want to use that
particular value, what bearing it has on anything or why it would
assume it could use 1/3 of the total RAM in the system (potentially
quite a large amount of RAM) as opposed to any other limit number.

Instead, hardcode 32Mby.

This reverts 22830:c80960244942, removes the xc_get_physmem/physmem
function entirely, and replaces the expression at the call site with a
fixed constant.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Cc: Christoph Egger <Christoph.Egger@amd.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
author Ian Jackson <Ian.Jackson@eu.citrix.com>
date Fri Jan 28 19:37:49 2011 +0000 (2011-01-28)
parents 88cf07fed7d2
children e7b31cc0093c
files tools/libxc/xc_dom_bzimageloader.c tools/libxc/xc_linux.c tools/libxc/xc_netbsd.c tools/libxc/xc_private.h
line diff
     1.1 --- a/tools/libxc/xc_dom_bzimageloader.c	Fri Jan 28 18:39:09 2011 +0000
     1.2 +++ b/tools/libxc/xc_dom_bzimageloader.c	Fri Jan 28 19:37:49 2011 +0000
     1.3 @@ -152,7 +152,7 @@ static int xc_try_lzma_decode(
     1.4      int outsize;
     1.5      const char *msg;
     1.6  
     1.7 -    ret = lzma_alone_decoder(&stream, xc_get_physmem() / 3);
     1.8 +    ret = lzma_alone_decoder(&stream, 32*1024*1024);
     1.9      if ( ret != LZMA_OK )
    1.10      {
    1.11          DOMPRINTF("LZMA: Failed to init stream decoder");
     2.1 --- a/tools/libxc/xc_linux.c	Fri Jan 28 18:39:09 2011 +0000
     2.2 +++ b/tools/libxc/xc_linux.c	Fri Jan 28 19:37:49 2011 +0000
     2.3 @@ -55,27 +55,6 @@ void discard_file_cache(xc_interface *xc
     2.4      errno = saved_errno;
     2.5  }
     2.6  
     2.7 -uint64_t xc_get_physmem(void)
     2.8 -{
     2.9 -    uint64_t ret = 0;
    2.10 -    const long pagesize = sysconf(_SC_PAGESIZE);
    2.11 -    const long pages = sysconf(_SC_PHYS_PAGES);
    2.12 -
    2.13 -    if ( (pagesize != -1) || (pages != -1) )
    2.14 -    {
    2.15 -        /*
    2.16 -         * According to docs, pagesize * pages can overflow.
    2.17 -         * Simple case is 32-bit box with 4 GiB or more RAM,
    2.18 -         * which may report exactly 4 GiB of RAM, and "long"
    2.19 -         * being 32-bit will overflow. Casting to uint64_t
    2.20 -         * hopefully avoids overflows in the near future.
    2.21 -         */
    2.22 -        ret = (uint64_t)(pagesize) * (uint64_t)(pages);
    2.23 -    }
    2.24 -
    2.25 -    return ret;
    2.26 -}
    2.27 -
    2.28  /*
    2.29   * Local variables:
    2.30   * mode: C
     3.1 --- a/tools/libxc/xc_netbsd.c	Fri Jan 28 18:39:09 2011 +0000
     3.2 +++ b/tools/libxc/xc_netbsd.c	Fri Jan 28 19:37:49 2011 +0000
     3.3 @@ -23,9 +23,6 @@
     3.4  #include <xen/sys/evtchn.h>
     3.5  #include <unistd.h>
     3.6  #include <fcntl.h>
     3.7 -#include <stdio.h>
     3.8 -#include <errno.h>
     3.9 -#include <sys/sysctl.h>
    3.10  
    3.11  static xc_osdep_handle netbsd_privcmd_open(xc_interface *xch)
    3.12  {
    3.13 @@ -354,24 +351,6 @@ void discard_file_cache(xc_interface *xc
    3.14      errno = saved_errno;
    3.15  }
    3.16  
    3.17 -uint64_t xc_get_physmem(void)
    3.18 -{
    3.19 -    int mib[2], rc;
    3.20 -    size_t len;
    3.21 -    uint64_t physmem;
    3.22 -
    3.23 -    mib[0] = CTL_HW;
    3.24 -    mib[1] = HW_PHYSMEM64;
    3.25 -    rc = sysctl(mib, 2, &physmem, &len, NULL, 0);
    3.26 -
    3.27 -    if (rc == -1) {
    3.28 -        /* PERROR("%s: Failed to get hw.physmem64: %s\n", strerror(errno)); */
    3.29 -        return 0;
    3.30 -    }
    3.31 -
    3.32 -    return physmem;
    3.33 -}
    3.34 -
    3.35  static struct xc_osdep_ops *netbsd_osdep_init(xc_interface *xch, enum xc_osdep_type type)
    3.36  {
    3.37      switch ( type )
     4.1 --- a/tools/libxc/xc_private.h	Fri Jan 28 18:39:09 2011 +0000
     4.2 +++ b/tools/libxc/xc_private.h	Fri Jan 28 19:37:49 2011 +0000
     4.3 @@ -275,9 +275,6 @@ void bitmap_byte_to_64(uint64_t *lp, con
     4.4  /* Optionally flush file to disk and discard page cache */
     4.5  void discard_file_cache(xc_interface *xch, int fd, int flush);
     4.6  
     4.7 -/* How much physical RAM is available? */
     4.8 -uint64_t xc_get_physmem(void);
     4.9 -
    4.10  #define MAX_MMU_UPDATES 1024
    4.11  struct xc_mmu {
    4.12      mmu_update_t updates[MAX_MMU_UPDATES];