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* util: Clean up includesPeter Maydell2019-11-291-2/+1
| | | | | | | | | | Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1454089805-5470-6-git-send-email-peter.maydell@linaro.org
* mmap-alloc: tweak a comment on ppc64Michael S. Tsirkin2019-11-291-4/+5
| | | | | | | | | | | | | | | | The comment I put in mmap-alloc to document the ppc64 rules refers to the previous revision of the patch: we don't look at memory alignment anymore, we check the fs from which the fd is mapped, instead. It's also not clear what does "in this case" refer to, rearrange text to make it clearer. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* util/mmap-alloc: fix hugetlb support on ppc64Michael S. Tsirkin2015-12-021-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 8561c9244ddf1122d "exec: allocate PROT_NONE pages on top of RAM", it is no longer possible to back guest RAM with hugepages on ppc64 hosts: mmap(NULL, 285212672, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x3fff57000000 mmap(0x3fff57000000, 268435456, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 19, 0) = -1 EBUSY (Device or resource busy) This is because on ppc64, Linux fixes a page size for a virtual address at mmap time, so we can't switch a range of memory from anonymous small pages to hugetlbs with MAP_FIXED. See commit d0f13e3c20b6fb73ccb467bdca97fa7cf5a574cd ("[POWERPC] Introduce address space "slices"") in Linux history for the details. Detect this and create the PROT_NONE mapping using the same fd. Naturally, this makes the guard page bigger with hugetlbfs. Based on patch by Greg Kurz. Acked-by: Rik van Riel <riel@redhat.com> Reviewed-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* mmap-alloc: fix error handlingMichael S. Tsirkin2015-10-291-2/+2
| | | | | | | | | | Existing callers are checking for MAP_FAILED, so we should return that on error. Reported-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* exec: factor out duplicate mmap codeMichael S. Tsirkin2015-10-211-0/+71
Anonymous and file-backed RAM allocation are now almost exactly the same. Reduce code duplication by moving RAM mmap code out of oslib-posix.c and exec.c. Reported-by: Marc-André Lureau <mlureau@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
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