| Message ID | 1598875533-19947-3-git-send-email-pmorel@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: css: adapting the I/O tests for PV | expand |
On Mon, 31 Aug 2020 14:05:32 +0200 Pierre Morel <pmorel@linux.ibm.com> wrote: > To centralize the memory allocation for I/O we define > the alloc/free_io_page() functions which share the I/O > memory with the host in case the guest runs with > protected virtualization. > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > --- > lib/s390x/malloc_io.c | 53 +++++++++++++++++++++++++++++++++++++++++++ > lib/s390x/malloc_io.h | 14 ++++++++++++ > s390x/Makefile | 1 + > 3 files changed, 68 insertions(+) > create mode 100644 lib/s390x/malloc_io.c > create mode 100644 lib/s390x/malloc_io.h > > diff --git a/lib/s390x/malloc_io.c b/lib/s390x/malloc_io.c > new file mode 100644 > index 0000000..0e67aab > --- /dev/null > +++ b/lib/s390x/malloc_io.c > @@ -0,0 +1,53 @@ > +/* > + * I/O page allocation > + * > + * Copyright (c) 2020 IBM Corp > + * > + * Authors: > + * Pierre Morel <pmorel@linux.ibm.com> > + * > + * This code is free software; you can redistribute it and/or modify it > + * under the terms of the GNU General Public License version 2. > + * > + * Using this interface provide host access to the allocated pages in > + * case the guest is a secure guest. > + * This is needed for I/O buffers. > + * > + */ > + > +#include <libcflat.h> > +#include <alloc_page.h> > +#include <asm/page.h> > +#include <asm/uv.h> > +#include <malloc_io.h> > +#include <asm/facility.h> > + > + > +void *alloc_io_page(int size) > +{ > + void *p; > + > + assert(size <= PAGE_SIZE); > + p = alloc_page(); I see that you use this for some I/O structures in the next patch. Is this guaranteed to be under 2G all the time?
On 2020-09-11 14:40, Cornelia Huck wrote: > On Mon, 31 Aug 2020 14:05:32 +0200 > Pierre Morel <pmorel@linux.ibm.com> wrote: > >> To centralize the memory allocation for I/O we define >> the alloc/free_io_page() functions which share the I/O >> memory with the host in case the guest runs with >> protected virtualization. ... >> + >> +void *alloc_io_page(int size) >> +{ >> + void *p; >> + >> + assert(size <= PAGE_SIZE); >> + p = alloc_page(); > > I see that you use this for some I/O structures in the next patch. Is > this guaranteed to be under 2G all the time? > Good catch. I forgot that I already worked on this problem a while ago, I will rework the allocation. Thanks, Pierre
diff --git a/lib/s390x/malloc_io.c b/lib/s390x/malloc_io.c new file mode 100644 index 0000000..0e67aab --- /dev/null +++ b/lib/s390x/malloc_io.c @@ -0,0 +1,53 @@ +/* + * I/O page allocation + * + * Copyright (c) 2020 IBM Corp + * + * Authors: + * Pierre Morel <pmorel@linux.ibm.com> + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2. + * + * Using this interface provide host access to the allocated pages in + * case the guest is a secure guest. + * This is needed for I/O buffers. + * + */ + +#include <libcflat.h> +#include <alloc_page.h> +#include <asm/page.h> +#include <asm/uv.h> +#include <malloc_io.h> +#include <asm/facility.h> + + +void *alloc_io_page(int size) +{ + void *p; + + assert(size <= PAGE_SIZE); + p = alloc_page(); + if (!p) { + report(0, "Memory allocation"); + return NULL; + } + + if (!test_facility(158)) + return p; + + if (!uv_set_shared((unsigned long)p)) { + report(0, "Sharing memory"); + return NULL; + } + + return p; +} + +void free_io_page(void *p) +{ + if (test_facility(158) && !uv_remove_shared((unsigned long)p)) + report(0, "Unsharing memory"); + free_page(p); +} diff --git a/lib/s390x/malloc_io.h b/lib/s390x/malloc_io.h new file mode 100644 index 0000000..6916f55 --- /dev/null +++ b/lib/s390x/malloc_io.h @@ -0,0 +1,14 @@ +/* + * I/O allocations + * + * Copyright (c) 2020 IBM Corp + * + * Authors: + * Pierre Morel <pmorel@linux.ibm.com> + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2. + */ + +void *alloc_io_page(int size); +void free_io_page(void *p); diff --git a/s390x/Makefile b/s390x/Makefile index 9144d57..f545597 100644 --- a/s390x/Makefile +++ b/s390x/Makefile @@ -62,6 +62,7 @@ cflatobjs += lib/s390x/smp.o cflatobjs += lib/s390x/vm.o cflatobjs += lib/s390x/css_dump.o cflatobjs += lib/s390x/css_lib.o +cflatobjs += lib/s390x/malloc_io.o OBJDIRS += lib/s390x
To centralize the memory allocation for I/O we define the alloc/free_io_page() functions which share the I/O memory with the host in case the guest runs with protected virtualization. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> --- lib/s390x/malloc_io.c | 53 +++++++++++++++++++++++++++++++++++++++++++ lib/s390x/malloc_io.h | 14 ++++++++++++ s390x/Makefile | 1 + 3 files changed, 68 insertions(+) create mode 100644 lib/s390x/malloc_io.c create mode 100644 lib/s390x/malloc_io.h