Merge tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from Konrad Rzeszutek Wilk:
 "Two major features that Xen community is excited about:

  The first is event channel scalability by David Vrabel - we switch
  over from an two-level per-cpu bitmap of events (IRQs) - to an FIFO
  queue with priorities.  This lets us be able to handle more events,
  have lower latency, and better scalability.  Good stuff.

  The other is PVH by Mukesh Rathor.  In short, PV is a mode where the
  kernel lets the hypervisor program page-tables, segments, etc.  With
  EPT/NPT capabilities in current processors, the overhead of doing this
  in an HVM (Hardware Virtual Machine) container is much lower than the
  hypervisor doing it for us.

  In short we let a PV guest run without doing page-table, segment,
  syscall, etc updates through the hypervisor - instead it is all done
  within the guest container.  It is a "hybrid" PV - hence the 'PVH'
  name - a PV guest within an HVM container.

  The major benefits are less code to deal with - for example we only
  use one function from the the pv_mmu_ops (which has 39 function
  calls); faster performance for syscall (no context switches into the
  hypervisor); less traps on various operations; etc.

  It is still being baked - the ABI is not yet set in stone.  But it is
  pretty awesome and we are excited about it.

  Lastly, there are some changes to ARM code - you should get a simple
  conflict which has been resolved in #linux-next.

  In short, this pull has awesome features.

  Features:
   - FIFO event channels.  Key advantages: support for over 100,000
     events (2^17), 16 different event priorities, improved fairness in
     event latency through the use of FIFOs.
   - Xen PVH support.  "It’s a fully PV kernel mode, running with
     paravirtualized disk and network, paravirtualized interrupts and
     timers, no emulated devices of any kind (and thus no qemu), no BIOS
     or legacy boot — but instead of requiring PV MMU, it uses the HVM
     hardware extensions to virtualize the pagetables, as well as system
     calls and other privileged operations." (from "The
     Paravirtualization Spectrum, Part 2: From poles to a spectrum")

  Bug-fixes:
   - Fixes in balloon driver (refactor and make it work under ARM)
   - Allow xenfb to be used in HVM guests.
   - Allow xen_platform_pci=0 to work properly.
   - Refactors in event channels"

* tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (52 commits)
  xen/pvh: Set X86_CR0_WP and others in CR0 (v2)
  MAINTAINERS: add git repository for Xen
  xen/pvh: Use 'depend' instead of 'select'.
  xen: delete new instances of __cpuinit usage
  xen/fb: allow xenfb initialization for hvm guests
  xen/evtchn_fifo: fix error return code in evtchn_fifo_setup()
  xen-platform: fix error return code in platform_pci_init()
  xen/pvh: remove duplicated include from enlighten.c
  xen/pvh: Fix compile issues with xen_pvh_domain()
  xen: Use dev_is_pci() to check whether it is pci device
  xen/grant-table: Force to use v1 of grants.
  xen/pvh: Support ParaVirtualized Hardware extensions (v3).
  xen/pvh: Piggyback on PVHVM XenBus.
  xen/pvh: Piggyback on PVHVM for grant driver (v4)
  xen/grant: Implement an grant frame array struct (v3).
  xen/grant-table: Refactor gnttab_init
  xen/grants: Remove gnttab_max_grant_frames dependency on gnttab_init.
  xen/pvh: Piggyback on PVHVM for event channels (v2)
  xen/pvh: Update E820 to work with PVH (v2)
  xen/pvh: Secondary VCPU bringup (non-bootup CPUs)
  ...

1 files changed, 65 insertions, 25 deletions

diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index aa846a48f400..1ce1c40331f3 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -62,12 +62,10 @@
 
 static grant_ref_t **gnttab_list;
 static unsigned int nr_grant_frames;
-static unsigned int boot_max_nr_grant_frames;
 static int gnttab_free_count;
 static grant_ref_t gnttab_free_head;
 static DEFINE_SPINLOCK(gnttab_list_lock);
-unsigned long xen_hvm_resume_frames;
-EXPORT_SYMBOL_GPL(xen_hvm_resume_frames);
+struct grant_frames xen_auto_xlat_grant_frames;
 
 static union {
 	struct grant_entry_v1 *v1;
@@ -827,6 +825,11 @@ static unsigned int __max_nr_grant_frames(void)
 unsigned int gnttab_max_grant_frames(void)
 {
 	unsigned int xen_max = __max_nr_grant_frames();
+	static unsigned int boot_max_nr_grant_frames;
+
+	/* First time, initialize it properly. */
+	if (!boot_max_nr_grant_frames)
+		boot_max_nr_grant_frames = __max_nr_grant_frames();
 
 	if (xen_max > boot_max_nr_grant_frames)
 		return boot_max_nr_grant_frames;
@@ -834,6 +837,51 @@ unsigned int gnttab_max_grant_frames(void)
 }
 EXPORT_SYMBOL_GPL(gnttab_max_grant_frames);
 
+int gnttab_setup_auto_xlat_frames(unsigned long addr)
+{
+	xen_pfn_t *pfn;
+	unsigned int max_nr_gframes = __max_nr_grant_frames();
+	unsigned int i;
+	void *vaddr;
+
+	if (xen_auto_xlat_grant_frames.count)
+		return -EINVAL;
+
+	vaddr = xen_remap(addr, PAGE_SIZE * max_nr_gframes);
+	if (vaddr == NULL) {
+		pr_warn("Failed to ioremap gnttab share frames (addr=0x%08lx)!\n",
+			addr);
+		return -ENOMEM;
+	}
+	pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL);
+	if (!pfn) {
+		xen_unmap(vaddr);
+		return -ENOMEM;
+	}
+	for (i = 0; i < max_nr_gframes; i++)
+		pfn[i] = PFN_DOWN(addr) + i;
+
+	xen_auto_xlat_grant_frames.vaddr = vaddr;
+	xen_auto_xlat_grant_frames.pfn = pfn;
+	xen_auto_xlat_grant_frames.count = max_nr_gframes;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(gnttab_setup_auto_xlat_frames);
+
+void gnttab_free_auto_xlat_frames(void)
+{
+	if (!xen_auto_xlat_grant_frames.count)
+		return;
+	kfree(xen_auto_xlat_grant_frames.pfn);
+	xen_unmap(xen_auto_xlat_grant_frames.vaddr);
+
+	xen_auto_xlat_grant_frames.pfn = NULL;
+	xen_auto_xlat_grant_frames.count = 0;
+	xen_auto_xlat_grant_frames.vaddr = NULL;
+}
+EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames);
+
 /* Handling of paged out grant targets (GNTST_eagain) */
 #define MAX_DELAY 256
 static inline void
@@ -1060,10 +1108,11 @@ static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
 	unsigned int nr_gframes = end_idx + 1;
 	int rc;
 
-	if (xen_hvm_domain()) {
+	if (xen_feature(XENFEAT_auto_translated_physmap)) {
 		struct xen_add_to_physmap xatp;
 		unsigned int i = end_idx;
 		rc = 0;
+		BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes);
 		/*
 		 * Loop backwards, so that the first hypercall has the largest
 		 * index, ensuring that the table will grow only once.
@@ -1072,7 +1121,7 @@ static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
 			xatp.domid = DOMID_SELF;
 			xatp.idx = i;
 			xatp.space = XENMAPSPACE_grant_table;
-			xatp.gpfn = (xen_hvm_resume_frames >> PAGE_SHIFT) + i;
+			xatp.gpfn = xen_auto_xlat_grant_frames.pfn[i];
 			rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
 			if (rc != 0) {
 				pr_warn("grant table add_to_physmap failed, err=%d\n",
@@ -1135,10 +1184,8 @@ static void gnttab_request_version(void)
 	int rc;
 	struct gnttab_set_version gsv;
 
-	if (xen_hvm_domain())
-		gsv.version = 1;
-	else
-		gsv.version = 2;
+	gsv.version = 1;
+
 	rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1);
 	if (rc == 0 && gsv.version == 2) {
 		grant_table_version = 2;
@@ -1169,22 +1216,15 @@ static int gnttab_setup(void)
 	if (max_nr_gframes < nr_grant_frames)
 		return -ENOSYS;
 
-	if (xen_pv_domain())
-		return gnttab_map(0, nr_grant_frames - 1);
-
-	if (gnttab_shared.addr == NULL) {
-		gnttab_shared.addr = xen_remap(xen_hvm_resume_frames,
-						PAGE_SIZE * max_nr_gframes);
+	if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) {
+		gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr;
 		if (gnttab_shared.addr == NULL) {
-			pr_warn("Failed to ioremap gnttab share frames (addr=0x%08lx)!\n",
-					xen_hvm_resume_frames);
+			pr_warn("gnttab share frames (addr=0x%08lx) is not mapped!\n",
+				(unsigned long)xen_auto_xlat_grant_frames.vaddr);
 			return -ENOMEM;
 		}
 	}
-
-	gnttab_map(0, nr_grant_frames - 1);
-
-	return 0;
+	return gnttab_map(0, nr_grant_frames - 1);
 }
 
 int gnttab_resume(void)
@@ -1227,13 +1267,12 @@ int gnttab_init(void)
 
 	gnttab_request_version();
 	nr_grant_frames = 1;
-	boot_max_nr_grant_frames = __max_nr_grant_frames();
 
 	/* Determine the maximum number of frames required for the
 	 * grant reference free list on the current hypervisor.
 	 */
 	BUG_ON(grefs_per_grant_frame == 0);
-	max_nr_glist_frames = (boot_max_nr_grant_frames *
+	max_nr_glist_frames = (gnttab_max_grant_frames() *
 			       grefs_per_grant_frame / RPP);
 
 	gnttab_list = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *),
@@ -1286,5 +1325,6 @@ static int __gnttab_init(void)
 
 	return gnttab_init();
 }
-
-core_initcall(__gnttab_init);
+/* Starts after core_initcall so that xen_pvh_gnttab_setup can be called
+ * beforehand to initialize xen_auto_xlat_grant_frames. */
+core_initcall_sync(__gnttab_init);