Linux 5.8 compat: __vmalloc()

The `pgprot` argument has been removed from `__vmalloc` in Linux 5.8,
being `PAGE_KERNEL` always now [1].

Detect this during configure and define a wrapper for older kernels.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/mm/vmalloc.c?h=next-20200605&id=88dca4ca5a93d2c09e5bbc6a62fbfc3af83c4fca

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
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>
Closes #10422
This commit is contained in:
Michael Niewöhner 2020-06-09 01:32:02 +02:00 committed by GitHub
parent 529246df96
commit 080102a1b6
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 46 additions and 11 deletions

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@ -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)
])
])
-

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@ -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

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@ -172,6 +172,15 @@ extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
extern void spl_kmem_free(const void *ptr, size_t sz);
/*
* 5.8 API change, pgprot_t argument removed.
*/
#ifdef HAVE_VMALLOC_PAGE_KERNEL
#define spl_vmalloc(size, flags) __vmalloc(size, flags, PAGE_KERNEL)
#else
#define spl_vmalloc(size, flags) __vmalloc(size, flags)
#endif
/*
* The following functions are only available for internal use.
*/

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@ -203,7 +203,7 @@ kv_alloc(spl_kmem_cache_t *skc, int size, int flags)
ASSERT(ISP2(size));
ptr = (void *)__get_free_pages(lflags, get_order(size));
} else {
ptr = __vmalloc(size, lflags | __GFP_HIGHMEM, PAGE_KERNEL);
ptr = spl_vmalloc(size, lflags | __GFP_HIGHMEM);
}
/* Resulting allocated memory will be page aligned */
@ -1251,7 +1251,7 @@ spl_cache_grow(spl_kmem_cache_t *skc, int flags, void **obj)
* allocation.
*
* However, this can't be applied to KVM_VMEM due to a bug that
* __vmalloc() doesn't honor gfp flags in page table allocation.
* spl_vmalloc() doesn't honor gfp flags in page table allocation.
*/
if (!(skc->skc_flags & KMC_VMEM) && !(skc->skc_flags & KMC_KVMEM)) {
rc = __spl_cache_grow(skc, flags | KM_NOSLEEP);

View File

@ -26,7 +26,6 @@
#include <sys/sysmacros.h>
#include <sys/kmem.h>
#include <sys/vmem.h>
#include <linux/mm.h>
/*
* As a general rule kmem_alloc() allocations should be small, preferably
@ -188,12 +187,12 @@ spl_kvmalloc(size_t size, gfp_t lflags)
/*
* We first try kmalloc - even for big sizes - and fall back to
* __vmalloc if that fails.
* spl_vmalloc if that fails.
*
* For non-__GFP-RECLAIM allocations we always stick to
* kmalloc_node, and fail when kmalloc is not successful (returns
* NULL).
* We cannot fall back to __vmalloc in this case because __vmalloc
* We cannot fall back to spl_vmalloc in this case because spl_vmalloc
* internally uses GPF_KERNEL allocations.
*/
void *ptr = kmalloc_node(size, kmalloc_lflags, NUMA_NO_NODE);
@ -202,7 +201,7 @@ spl_kvmalloc(size_t size, gfp_t lflags)
return (ptr);
}
return (__vmalloc(size, lflags | __GFP_HIGHMEM, PAGE_KERNEL));
return (spl_vmalloc(size, lflags | __GFP_HIGHMEM));
}
/*
@ -243,16 +242,15 @@ spl_kmem_alloc_impl(size_t size, int flags, int node)
* kmem_zalloc() callers.
*
* For vmem_alloc() and vmem_zalloc() callers it is permissible
* to use __vmalloc(). However, in general use of __vmalloc()
* is strongly discouraged because a global lock must be
* acquired. Contention on this lock can significantly
* to use spl_vmalloc(). However, in general use of
* spl_vmalloc() is strongly discouraged because a global lock
* must be acquired. Contention on this lock can significantly
* impact performance so frequently manipulating the virtual
* address space is strongly discouraged.
*/
if (size > spl_kmem_alloc_max) {
if (flags & KM_VMEM) {
ptr = __vmalloc(size, lflags | __GFP_HIGHMEM,
PAGE_KERNEL);
ptr = spl_vmalloc(size, lflags | __GFP_HIGHMEM);
} else {
return (NULL);
}