From: Christophe Leroy christophe.leroy@csgroup.eu
mainline inclusion from mainline-5.13-rc2 commit 86d0c164272536c732853e19391de5159f860701 category: feature bugzilla: NA CVE: NA
---------------------------
iomap_max_page_shift is expected to contain a page shift, so it can't be a 'bool', has to be an 'unsigned int'
And fix the default values: P4D_SHIFT is when huge iomap is allowed.
However, on some architectures (eg: powerpc book3s/64), P4D_SHIFT is not a constant so it can't be used to initialise a static variable. So, initialise iomap_max_page_shift with a maximum shift supported by the architecture, it is gated by P4D_SHIFT in vmap_try_huge_p4d() anyway.
Link: https://lkml.kernel.org/r/ad2d366015794a9f21320dcbdd0a8eb98979e9df.162089811... Fixes: bbc180a5adb0 ("mm: HUGE_VMAP arch support cleanup") Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Reviewed-by: Nicholas Piggin npiggin@gmail.com Reviewed-by: Anshuman Khandual anshuman.khandual@arm.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Rui Xiang rui.xiang@huawei.com Reviewed-by: Tang Yizhou tangyizhou@huawei.com Reviewed-by: Ding Tianhong dingtianhong@huawei.com Reviewed-by: Weilong Chen chenweilong@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- mm/ioremap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/mm/ioremap.c b/mm/ioremap.c index 8b1905bf03d26..53827cbf4c2cb 100644 --- a/mm/ioremap.c +++ b/mm/ioremap.c @@ -15,16 +15,16 @@ #include <asm/pgtable.h>
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP -static bool __ro_after_init iomap_max_page_shift = PAGE_SHIFT; +static unsigned int __ro_after_init iomap_max_page_shift = BITS_PER_LONG - 1;
static int __init set_nohugeiomap(char *str) { - iomap_max_page_shift = P4D_SHIFT; + iomap_max_page_shift = PAGE_SHIFT; return 0; } early_param("nohugeiomap", set_nohugeiomap); #else /* CONFIG_HAVE_ARCH_HUGE_VMAP */ -static const bool iomap_max_page_shift = PAGE_SHIFT; +static const unsigned int iomap_max_page_shift = PAGE_SHIFT; #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
int ioremap_page_range(unsigned long addr,