[PATCH v3 02/17] xen/grant-table: Move xlated_setup_gnttab_pages to common place

From: Shannon Zhao
Date: Fri Jan 22 2016 - 22:24:34 EST


From: Shannon Zhao <shannon.zhao@xxxxxxxxxx>

Move xlated_setup_gnttab_pages to common place, so it can be reused by
ARM to setup grant table.

Rename it to xen_xlate_map_ballooned_pages.

Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
Reviewed-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
---
arch/x86/xen/grant-table.c | 57 +++++--------------------------------------
drivers/xen/xlate_mmu.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++
include/xen/xen-ops.h | 2 ++
3 files changed, 69 insertions(+), 51 deletions(-)

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index e079500..de4144c 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -111,63 +111,18 @@ int arch_gnttab_init(unsigned long nr_shared)
}

#ifdef CONFIG_XEN_PVH
-#include <xen/balloon.h>
#include <xen/events.h>
-#include <linux/slab.h>
-static int __init xlated_setup_gnttab_pages(void)
-{
- struct page **pages;
- xen_pfn_t *pfns;
- void *vaddr;
- int rc;
- unsigned int i;
- unsigned long nr_grant_frames = gnttab_max_grant_frames();
-
- BUG_ON(nr_grant_frames == 0);
- pages = kcalloc(nr_grant_frames, sizeof(pages[0]), GFP_KERNEL);
- if (!pages)
- return -ENOMEM;
-
- pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
- if (!pfns) {
- kfree(pages);
- return -ENOMEM;
- }
- rc = alloc_xenballooned_pages(nr_grant_frames, pages);
- if (rc) {
- pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
- nr_grant_frames, rc);
- kfree(pages);
- kfree(pfns);
- return rc;
- }
- for (i = 0; i < nr_grant_frames; i++)
- pfns[i] = page_to_pfn(pages[i]);
-
- vaddr = vmap(pages, nr_grant_frames, 0, PAGE_KERNEL);
- if (!vaddr) {
- pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
- nr_grant_frames, rc);
- free_xenballooned_pages(nr_grant_frames, pages);
- kfree(pages);
- kfree(pfns);
- return -ENOMEM;
- }
- kfree(pages);
-
- xen_auto_xlat_grant_frames.pfn = pfns;
- xen_auto_xlat_grant_frames.count = nr_grant_frames;
- xen_auto_xlat_grant_frames.vaddr = vaddr;
-
- return 0;
-}
-
+#include <xen/xen-ops.h>
static int __init xen_pvh_gnttab_setup(void)
{
if (!xen_pvh_domain())
return -ENODEV;

- return xlated_setup_gnttab_pages();
+ xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames();
+
+ return xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn,
+ &xen_auto_xlat_grant_frames.vaddr,
+ xen_auto_xlat_grant_frames.count);
}
/* Call it _before_ __gnttab_init as we need to initialize the
* xen_auto_xlat_grant_frames first. */
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
index 5063c5e..9692656 100644
--- a/drivers/xen/xlate_mmu.c
+++ b/drivers/xen/xlate_mmu.c
@@ -29,6 +29,8 @@
*/
#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>

#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
@@ -37,6 +39,7 @@
#include <xen/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/memory.h>
+#include <xen/balloon.h>

typedef void (*xen_gfn_fn_t)(unsigned long gfn, void *data);

@@ -185,3 +188,61 @@ int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
return 0;
}
EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);
+
+/**
+ * xen_xlate_map_ballooned_pages - map a new set of ballooned pages
+ * @gfns: returns the array of corresponding GFNs
+ * @virt: returns the virtual address of the mapped region
+ * @nr_grant_frames: number of GFNs
+ * @return 0 on success, error otherwise
+ *
+ * This allocates a set of ballooned pages and maps them into the
+ * kernel's address space.
+ */
+int __init xen_xlate_map_ballooned_pages(xen_pfn_t **gfns, void **virt,
+ unsigned long nr_grant_frames)
+{
+ struct page **pages;
+ xen_pfn_t *pfns;
+ void *vaddr;
+ int rc;
+ unsigned int i;
+
+ BUG_ON(nr_grant_frames == 0);
+ pages = kcalloc(nr_grant_frames, sizeof(pages[0]), GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
+ if (!pfns) {
+ kfree(pages);
+ return -ENOMEM;
+ }
+ rc = alloc_xenballooned_pages(nr_grant_frames, pages);
+ if (rc) {
+ pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
+ nr_grant_frames, rc);
+ kfree(pages);
+ kfree(pfns);
+ return rc;
+ }
+ for (i = 0; i < nr_grant_frames; i++)
+ pfns[i] = page_to_pfn(pages[i]);
+
+ vaddr = vmap(pages, nr_grant_frames, 0, PAGE_KERNEL);
+ if (!vaddr) {
+ pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
+ nr_grant_frames, rc);
+ free_xenballooned_pages(nr_grant_frames, pages);
+ kfree(pages);
+ kfree(pfns);
+ return -ENOMEM;
+ }
+ kfree(pages);
+
+ *gfns = pfns;
+ *virt = vaddr;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_xlate_map_ballooned_pages);
diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
index e4e214a..42be31a 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h
@@ -80,6 +80,8 @@ int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
struct page **pages);
int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
int nr, struct page **pages);
+int xen_xlate_map_ballooned_pages(xen_pfn_t **pfns, void **vaddr,
+ unsigned long nr_grant_frames);

bool xen_running_on_version_or_later(unsigned int major, unsigned int minor);

--
2.0.4