[PATCH v17 19/35] arch/mm: Export direct {un,}map functions

From: Elliot Berman
Date: Thu Feb 22 2024 - 18:17:43 EST


Firmware and hypervisor drivers can donate system heap memory to their
respective firmware/hypervisor entities. Those drivers should unmap the
pages from the kernel's logical map before doing so.

Export can_set_direct_map, set_direct_map_invalid_noflush, and
set_direct_map_default_noflush.

Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
arch/arm64/mm/pageattr.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 924843f1f661b..a9bd84588c98a 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -32,6 +32,7 @@ bool can_set_direct_map(void)
return rodata_full || debug_pagealloc_enabled() ||
arm64_kfence_can_set_direct_map();
}
+EXPORT_SYMBOL_GPL(can_set_direct_map);

static int change_page_range(pte_t *ptep, unsigned long addr, void *data)
{
@@ -176,6 +177,7 @@ int set_direct_map_invalid_noflush(struct page *page)
(unsigned long)page_address(page),
PAGE_SIZE, change_page_range, &data);
}
+EXPORT_SYMBOL_GPL(set_direct_map_invalid_noflush);

int set_direct_map_default_noflush(struct page *page)
{
@@ -191,6 +193,7 @@ int set_direct_map_default_noflush(struct page *page)
(unsigned long)page_address(page),
PAGE_SIZE, change_page_range, &data);
}
+EXPORT_SYMBOL_GPL(set_direct_map_default_noflush);

#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)

--
2.34.1