Linux 5.8 __vmalloc compat

The pgprot argument has been removed from __vmalloc in Linux 5.8 [1], being `PAGE_KERNEL` always now. Detect this during configure to use the right function call in spl. [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/mm/vmalloc.c?h=next-20200605&id=88dca4ca5a93d2c09e5bbc6a62fbfc3af83c4fca Co-authored-by: Sebastian Gottschall <s.gottschall@dd-wrt.com> Co-authored-by: Michael Niewöhner <foss@mniewoehner.de> Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com> Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
openzfs · Jun 8, 2020 · cbc8971 · cbc8971
1 parent c9e319f
commit cbc8971
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diff --git a/config/kernel-kmem.m4 b/config/kernel-kmem.m4
@@ -80,3 +80,29 @@ AC_DEFUN([ZFS_AC_KERNEL_KVMALLOC], [
 		AC_MSG_RESULT(no)
 	])
 ])
+
+dnl #
+dnl # 5.8 API,
+dnl # __vmalloc PAGE_KERNEL removal
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_SRC_VMALLOC_PAGE_KERNEL], [
+	ZFS_LINUX_TEST_SRC([__vmalloc], [
+		#include <linux/mm.h>
+		#include <linux/vmalloc.h>
+	],[
+		void *p __attribute__ ((unused));
+
+		p = __vmalloc(0, GFP_KERNEL, PAGE_KERNEL);
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_VMALLOC_PAGE_KERNEL], [
+	AC_MSG_CHECKING([whether __vmalloc(ptr, flags, pageflags) is available])
+	ZFS_LINUX_TEST_RESULT([__vmalloc], [
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_VMALLOC_PAGE_KERNEL, 1, [__vmalloc page flags exists])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+-
diff --git a/config/kernel.m4 b/config/kernel.m4
@@ -47,6 +47,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
 	ZFS_AC_KERNEL_SRC_USLEEP_RANGE
 	ZFS_AC_KERNEL_SRC_KMEM_CACHE
 	ZFS_AC_KERNEL_SRC_KVMALLOC
+	ZFS_AC_KERNEL_SRC_VMALLOC_PAGE_KERNEL
 	ZFS_AC_KERNEL_SRC_WAIT
 	ZFS_AC_KERNEL_SRC_INODE_TIMES
 	ZFS_AC_KERNEL_SRC_INODE_LOCK
@@ -141,6 +142,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
 	ZFS_AC_KERNEL_USLEEP_RANGE
 	ZFS_AC_KERNEL_KMEM_CACHE
 	ZFS_AC_KERNEL_KVMALLOC
+	ZFS_AC_KERNEL_VMALLOC_PAGE_KERNEL
 	ZFS_AC_KERNEL_WAIT
 	ZFS_AC_KERNEL_INODE_TIMES
 	ZFS_AC_KERNEL_INODE_LOCK

diff --git a/module/os/linux/spl/spl-kmem-cache.c b/module/os/linux/spl/spl-kmem-cache.c
@@ -203,7 +203,11 @@ kv_alloc(spl_kmem_cache_t *skc, int size, int flags)
 		ASSERT(ISP2(size));
 		ptr = (void *)__get_free_pages(lflags, get_order(size));
 	} else {
+#ifdef HAVE_VMALLOC_PAGE_KERNEL
 		ptr = __vmalloc(size, lflags | __GFP_HIGHMEM, PAGE_KERNEL);
+#else
+		ptr = __vmalloc(size, lflags | __GFP_HIGHMEM);
+#endif
 	}
 
 	/* Resulting allocated memory will be page aligned */

diff --git a/module/os/linux/spl/spl-kmem.c b/module/os/linux/spl/spl-kmem.c
@@ -202,7 +202,11 @@ spl_kvmalloc(size_t size, gfp_t lflags)
 		return (ptr);
 	}
 
+#ifdef HAVE_VMALLOC_PAGE_KERNEL
 	return (__vmalloc(size, lflags | __GFP_HIGHMEM, PAGE_KERNEL));
+#else
+	return (__vmalloc(size, lflags | __GFP_HIGHMEM));
+#endif
 }
 
 /*
@@ -251,8 +255,12 @@ spl_kmem_alloc_impl(size_t size, int flags, int node)
 		 */
 		if (size > spl_kmem_alloc_max) {
 			if (flags & KM_VMEM) {
+#ifdef HAVE_VMALLOC_PAGE_KERNEL
 				ptr = __vmalloc(size, lflags | __GFP_HIGHMEM,
 				    PAGE_KERNEL);
+#else
+				ptr = __vmalloc(size, lflags | __GFP_HIGHMEM);
+#endif
 			} else {
 				return (NULL);
 			}