This is a note to let you know that I've just added the patch titled
xen: move max_pfn in xen_memory_setup() out of function scope
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xen-move-max_pfn-in-xen_memory_setup-out-of-function.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 96e05f7863867acad3a2f1a9fde01f59cb56b9e4
Author: Juergen Gross <jgross@xxxxxxxx>
Date: Tue Aug 6 10:24:41 2024 +0200
xen: move max_pfn in xen_memory_setup() out of function scope
[ Upstream commit 43dc2a0f479b9cd30f6674986d7a40517e999d31 ]
Instead of having max_pfn as a local variable of xen_memory_setup(),
make it a static variable in setup.c instead. This avoids having to
pass it to subfunctions, which will be needed in more cases in future.
Rename it to ini_nr_pages, as the value denotes the currently usable
number of memory pages as passed from the hypervisor at boot time.
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Tested-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Stable-dep-of: be35d91c8880 ("xen: tolerate ACPI NVS memory overlapping with Xen allocated memory")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 2fd89830b1ffb..64824e922c6ca 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -44,6 +44,9 @@ unsigned long xen_released_pages;
/* E820 map used during setting up memory. */
static struct e820_table xen_e820_table __initdata;
+/* Number of initially usable memory pages. */
+static unsigned long ini_nr_pages __initdata;
+
/*
* Buffer used to remap identity mapped pages. We only need the virtual space.
* The physical page behind this address is remapped as needed to different
@@ -251,7 +254,7 @@ static int __init xen_free_mfn(unsigned long mfn)
* as a fallback if the remapping fails.
*/
static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
- unsigned long end_pfn, unsigned long nr_pages)
+ unsigned long end_pfn)
{
unsigned long pfn, end;
int ret;
@@ -259,7 +262,7 @@ static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
WARN_ON(start_pfn > end_pfn);
/* Release pages first. */
- end = min(end_pfn, nr_pages);
+ end = min(end_pfn, ini_nr_pages);
for (pfn = start_pfn; pfn < end; pfn++) {
unsigned long mfn = pfn_to_mfn(pfn);
@@ -384,15 +387,14 @@ static void __init xen_do_set_identity_and_remap_chunk(
* to Xen and not remapped.
*/
static unsigned long __init xen_set_identity_and_remap_chunk(
- unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
- unsigned long remap_pfn)
+ unsigned long start_pfn, unsigned long end_pfn, unsigned long remap_pfn)
{
unsigned long pfn;
unsigned long i = 0;
unsigned long n = end_pfn - start_pfn;
if (remap_pfn == 0)
- remap_pfn = nr_pages;
+ remap_pfn = ini_nr_pages;
while (i < n) {
unsigned long cur_pfn = start_pfn + i;
@@ -401,19 +403,19 @@ static unsigned long __init xen_set_identity_and_remap_chunk(
unsigned long remap_range_size;
/* Do not remap pages beyond the current allocation */
- if (cur_pfn >= nr_pages) {
+ if (cur_pfn >= ini_nr_pages) {
/* Identity map remaining pages */
set_phys_range_identity(cur_pfn, cur_pfn + size);
break;
}
- if (cur_pfn + size > nr_pages)
- size = nr_pages - cur_pfn;
+ if (cur_pfn + size > ini_nr_pages)
+ size = ini_nr_pages - cur_pfn;
remap_range_size = xen_find_pfn_range(&remap_pfn);
if (!remap_range_size) {
pr_warning("Unable to find available pfn range, not remapping identity pages\n");
xen_set_identity_and_release_chunk(cur_pfn,
- cur_pfn + left, nr_pages);
+ cur_pfn + left);
break;
}
/* Adjust size to fit in current e820 RAM region */
@@ -440,18 +442,18 @@ static unsigned long __init xen_set_identity_and_remap_chunk(
}
static unsigned long __init xen_count_remap_pages(
- unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
+ unsigned long start_pfn, unsigned long end_pfn,
unsigned long remap_pages)
{
- if (start_pfn >= nr_pages)
+ if (start_pfn >= ini_nr_pages)
return remap_pages;
- return remap_pages + min(end_pfn, nr_pages) - start_pfn;
+ return remap_pages + min(end_pfn, ini_nr_pages) - start_pfn;
}
-static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages,
+static unsigned long __init xen_foreach_remap_area(
unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn,
- unsigned long nr_pages, unsigned long last_val))
+ unsigned long last_val))
{
phys_addr_t start = 0;
unsigned long ret_val = 0;
@@ -479,8 +481,7 @@ static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages,
end_pfn = PFN_UP(entry->addr);
if (start_pfn < end_pfn)
- ret_val = func(start_pfn, end_pfn, nr_pages,
- ret_val);
+ ret_val = func(start_pfn, end_pfn, ret_val);
start = end;
}
}
@@ -747,7 +748,7 @@ static void __init xen_reserve_xen_mfnlist(void)
**/
char * __init xen_memory_setup(void)
{
- unsigned long max_pfn, pfn_s, n_pfns;
+ unsigned long pfn_s, n_pfns;
phys_addr_t mem_end, addr, size, chunk_size;
u32 type;
int rc;
@@ -759,9 +760,8 @@ char * __init xen_memory_setup(void)
int op;
xen_parse_512gb();
- max_pfn = xen_get_pages_limit();
- max_pfn = min(max_pfn, xen_start_info->nr_pages);
- mem_end = PFN_PHYS(max_pfn);
+ ini_nr_pages = min(xen_get_pages_limit(), xen_start_info->nr_pages);
+ mem_end = PFN_PHYS(ini_nr_pages);
memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries);
set_xen_guest_handle(memmap.buffer, xen_e820_table.entries);
@@ -801,10 +801,10 @@ char * __init xen_memory_setup(void)
max_pages = xen_get_max_pages();
/* How many extra pages do we need due to remapping? */
- max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages);
+ max_pages += xen_foreach_remap_area(xen_count_remap_pages);
- if (max_pages > max_pfn)
- extra_pages += max_pages - max_pfn;
+ if (max_pages > ini_nr_pages)
+ extra_pages += max_pages - ini_nr_pages;
/*
* Clamp the amount of extra memory to a EXTRA_MEM_RATIO
@@ -820,8 +820,8 @@ char * __init xen_memory_setup(void)
* the initial memory is also very large with respect to
* lowmem, but we won't try to deal with that here.
*/
- maxmem_pages = EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM));
- extra_pages = min3(maxmem_pages, extra_pages, max_pages - max_pfn);
+ maxmem_pages = EXTRA_MEM_RATIO * min(ini_nr_pages, PFN_DOWN(MAXMEM));
+ extra_pages = min3(maxmem_pages, extra_pages, max_pages - ini_nr_pages);
i = 0;
addr = xen_e820_table.entries[0].addr;
size = xen_e820_table.entries[0].size;
@@ -923,7 +923,7 @@ char * __init xen_memory_setup(void)
* Set identity map on non-RAM pages and prepare remapping the
* underlying RAM.
*/
- xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk);
+ xen_foreach_remap_area(xen_set_identity_and_remap_chunk);
pr_info("Released %ld page(s)\n", xen_released_pages);
