Merge tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for direct mapped LPC on POWER9, giving Linux direct access
     to devices that may be on there such as a UART.

   - Memory hotplug support for the Power9 Radix MMU.

   - Add new AUX vectors describing the processor's cache geometry, to
     be used by glibc.

   - The ability for a guest to ask the hypervisor to resize the guest's
     hash table, and in addition support for doing so automatically when
     memory is hotplugged into/out-of the guest. This allows the hash
     table to be sized based on the current memory usage of the guest,
     rather than the maximum possible memory usage.

   - Implementation of optprobes (kprobe optimisation) for powerpc.

  In addition there's the topic branch shared with the KVM tree, which
  includes support for guests to use the Radix MMU on Power9.

  Thanks to:
    Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton
    Blanchard, Benjamin Herrenschmidt, Chris Packham, Daniel Axtens,
    Daniel Borkmann, David Gibson, Finn Thain, Gautham R. Shenoy, Gavin
    Shan, Greg Kurz, Joel Stanley, John Allen, Madhavan Srinivasan,
    Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Nathan Fontenot,
    Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Reza
    Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun"

* tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (129 commits)
  powerpc/mm/radix: Skip ptesync in pte update helpers
  powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
  powerpc/mm/radix: Update pte update sequence for pte clear case
  powerpc/mm: Update PROTFAULT handling in the page fault path
  powerpc/xmon: Fix data-breakpoint
  powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y
  powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=y
  powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n
  powerpc/pseries: Fix typo in parameter description
  powerpc/kprobes: Remove kprobe_exceptions_notify()
  kprobes: Introduce weak variant of kprobe_exceptions_notify()
  powerpc/ftrace: Fix confusing help text for DISABLE_MPROFILE_KERNEL
  powerpc/powernv: Fix opal_exit tracepoint opcode
  powerpc: Add a prototype for mcount() so it can be versioned
  powerpc: Drop GPL from of_node_to_nid() export to match other arches
  powerpc/kprobes: Optimize kprobe in kretprobe_trampoline()
  powerpc/kprobes: Implement Optprobes
  powerpc/kprobes: Fixes for kprobe_lookup_name() on BE
  powerpc: Add helper to check if offset is within relative branch range
  powerpc/bpf: Introduce __PPC_SH64()
  ...

1 files changed, 62 insertions, 0 deletions

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 67e19a0821be..12d679df50bd 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -35,7 +35,9 @@
 #include <linux/memblock.h>
 #include <linux/context_tracking.h>
 #include <linux/libfdt.h>
+#include <linux/debugfs.h>
 
+#include <asm/debug.h>
 #include <asm/processor.h>
 #include <asm/pgtable.h>
 #include <asm/mmu.h>
@@ -747,6 +749,35 @@ static unsigned long __init htab_get_table_size(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
+void resize_hpt_for_hotplug(unsigned long new_mem_size)
+{
+	unsigned target_hpt_shift;
+
+	if (!mmu_hash_ops.resize_hpt)
+		return;
+
+	target_hpt_shift = htab_shift_for_mem_size(new_mem_size);
+
+	/*
+	 * To avoid lots of HPT resizes if memory size is fluctuating
+	 * across a boundary, we deliberately have some hysterisis
+	 * here: we immediately increase the HPT size if the target
+	 * shift exceeds the current shift, but we won't attempt to
+	 * reduce unless the target shift is at least 2 below the
+	 * current shift
+	 */
+	if ((target_hpt_shift > ppc64_pft_size)
+	    || (target_hpt_shift < (ppc64_pft_size - 1))) {
+		int rc;
+
+		rc = mmu_hash_ops.resize_hpt(target_hpt_shift);
+		if (rc)
+			printk(KERN_WARNING
+			       "Unable to resize hash page table to target order %d: %d\n",
+			       target_hpt_shift, rc);
+	}
+}
+
 int hash__create_section_mapping(unsigned long start, unsigned long end)
 {
 	int rc = htab_bolt_mapping(start, end, __pa(start),
@@ -1795,3 +1826,34 @@ void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base,
 	/* Finally limit subsequent allocations */
 	memblock_set_current_limit(ppc64_rma_size);
 }
+
+#ifdef CONFIG_DEBUG_FS
+
+static int hpt_order_get(void *data, u64 *val)
+{
+	*val = ppc64_pft_size;
+	return 0;
+}
+
+static int hpt_order_set(void *data, u64 val)
+{
+	if (!mmu_hash_ops.resize_hpt)
+		return -ENODEV;
+
+	return mmu_hash_ops.resize_hpt(val);
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_hpt_order, hpt_order_get, hpt_order_set, "%llu\n");
+
+static int __init hash64_debugfs(void)
+{
+	if (!debugfs_create_file("hpt_order", 0600, powerpc_debugfs_root,
+				 NULL, &fops_hpt_order)) {
+		pr_err("lpar: unable to create hpt_order debugsfs file\n");
+	}
+
+	return 0;
+}
+machine_device_initcall(pseries, hash64_debugfs);
+
+#endif /* CONFIG_DEBUG_FS */