[PATCH v2 01/17] xen/riscv: implement sbi_remote_hfence_gvma()

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

Instruct the remote harts to execute one or more HFENCE.GVMA instructions,
covering the range of guest physical addresses between start_addr and
start_addr + size for all the guests.

The remote fence operation applies to the entire address space if either:
 - start_addr and size are both 0, or
 - size is equal to 2^XLEN-1.

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
---
Changes in V2:
 - New patch.
---
 xen/arch/riscv/include/asm/sbi.h | 21 +++++++++++++++++++++
 xen/arch/riscv/sbi.c             |  9 +++++++++
 2 files changed, 30 insertions(+)

diff --git a/xen/arch/riscv/include/asm/sbi.h b/xen/arch/riscv/include/asm/sbi.h
index 527d773277..8e346347af 100644
--- a/xen/arch/riscv/include/asm/sbi.h
+++ b/xen/arch/riscv/include/asm/sbi.h
@@ -89,6 +89,27 @@ bool sbi_has_rfence(void);
 int sbi_remote_sfence_vma(const cpumask_t *cpu_mask, vaddr_t start,
                           size_t size);
 
+/*
+ * Instructs the remote harts to execute one or more HFENCE.GVMA
+ * instructions, covering the range of guest physical addresses
+ * between start_addr and start_addr + size for all the guests.
+ * This function call is only valid for harts implementing
+ * hypervisor extension.
+ *
+ * Returns 0 if IPI was sent to all the targeted harts successfully
+ * or negative value if start_addr or size is not valid.
+ *
+ * The remote fence operation applies to the entire address space if either:
+ *  - start_addr and size are both 0, or
+ *  - size is equal to 2^XLEN-1.
+ *
+ * @cpu_mask a cpu mask containing all the target CPUs (in Xen space).
+ * @param start virtual address start
+ * @param size virtual address range size
+ */
+int sbi_remote_hfence_gvma(const cpumask_t *cpu_mask, vaddr_t start,
+                           size_t size);
+
 /*
  * Initialize SBI library
  *
diff --git a/xen/arch/riscv/sbi.c b/xen/arch/riscv/sbi.c
index 4209520389..0613ad1cb0 100644
--- a/xen/arch/riscv/sbi.c
+++ b/xen/arch/riscv/sbi.c
@@ -258,6 +258,15 @@ int sbi_remote_sfence_vma(const cpumask_t *cpu_mask, 
vaddr_t start,
                       cpu_mask, start, size, 0, 0);
 }
 
+int sbi_remote_hfence_gvma(const cpumask_t *cpu_mask, vaddr_t start,
+                           size_t size)
+{
+    ASSERT(sbi_rfence);
+
+    return sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA,
+                      cpu_mask, start, size, 0, 0);
+}
+
 /* This function must always succeed. */
 #define sbi_get_spec_version()  \
     sbi_ext_base_func(SBI_EXT_BASE_GET_SPEC_VERSION)
-- 
2.49.0