Hi Costin,
On 10/05/2021 09:35, Costin Lupu wrote:
@@ -168,7 +168,7 @@ void *osdep_xenforeignmemory_map(xenforeignmemory_handle
*fmem,
size_t i;
int rc;
- addr = mmap(addr, num << PAGE_SHIFT, prot, flags | MAP_SHARED,
+ addr = mmap(addr, num << XC_PAGE_SHIFT, prot, flags | MAP_SHARED,
fd, 0);
if ( addr == MAP_FAILED )
return NULL;
@@ -198,9 +198,10 @@ void *osdep_xenforeignmemory_map(xenforeignmemory_handle
*fmem,
*/
privcmd_mmapbatch_t ioctlx;
xen_pfn_t *pfn;
- unsigned int pfn_arr_size = ROUNDUP((num * sizeof(*pfn)), PAGE_SHIFT);
+ unsigned int pfn_arr_size = ROUNDUP((num * sizeof(*pfn)),
XC_PAGE_SHIFT);
+ int os_page_size = getpagesize();
Hmmm... Sorry I only realized now that the manpage suggests that
getpagesize() is legacy:
SVr4, 4.4BSD, SUSv2. In SUSv2 the getpagesize() call is labeled
LEGACY, and in POSIX.1-2001 it has been dropped; HP-UX does not have
this call.
And then:
Portable applications should employ sysconf(_SC_PAGESIZE) instead of
getpagesize():
#include <unistd.h>
long sz = sysconf(_SC_PAGESIZE);
As this is only used by Linux, it is not clear to me whether this is
important. Ian, what do you think?
- if ( pfn_arr_size <= PAGE_SIZE )
+ if ( pfn_arr_size <= os_page_size )
Your commit message suggests we are only s/PAGE_SHIFT/XC_PAGE_SHIFT/ but
this is using getpagesize() instead. I agree it should be using the OS
size. However, this should be clarified in the commit message.
The rest of the patch looks fine to me .
Cheers,
--
Julien Grall
