On 2019-10-03 20:12, Michael Kelley wrote:
Add ARM64-specific code to allocate memory with HV_HYP_PAGE_SIZE
size and alignment. These are for use when pages need to be shared
with Hyper-V. Separate functions are needed as the page size used
by Hyper-V may not be the same as the guest page size. Free
operations are rarely done, so no attempt is made to combine
freed pages into larger chunks.
This code is built only when CONFIG_HYPERV is enabled.
Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
---
arch/arm64/hyperv/hv_init.c | 68
++++++++++++++++++++++++++++++++++++++++++
include/asm-generic/mshyperv.h | 5 ++++
2 files changed, 73 insertions(+)
diff --git a/arch/arm64/hyperv/hv_init.c
b/arch/arm64/hyperv/hv_init.c
index 6808bc8..9c294f6 100644
--- a/arch/arm64/hyperv/hv_init.c
+++ b/arch/arm64/hyperv/hv_init.c
@@ -15,10 +15,78 @@
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/hyperv.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/string.h>
#include <asm-generic/bug.h>
#include <asm/hyperv-tlfs.h>
#include <asm/mshyperv.h>
+
+/*
+ * Functions for allocating and freeing memory with size and
+ * alignment HV_HYP_PAGE_SIZE. These functions are needed because
+ * the guest page size may not be the same as the Hyper-V page
+ * size. And while kalloc() could allocate the memory, it does not
+ * guarantee the required alignment. So a separate small memory
+ * allocator is needed. The free function is rarely used, so it
+ * does not try to combine freed pages into larger chunks.
Is this still needed now that kmalloc has alignment guarantees
(see 59bb47985c1d)?
M.
--
Jazz is not dead. It just smells funny...
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