[xen staging] x86/pv: Inline domain_set_alloc_bitsize() into it's single caller

[patchbot@xxxxxxx]

commit 156e27e4976e4586b06764b22a4c6525cbd92a68
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Tue Dec 9 17:51:19 2025 +0000
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Wed Dec 10 14:48:45 2025 +0000

    x86/pv: Inline domain_set_alloc_bitsize() into it's single caller
    
    Prior to commit 02e78311cdc6 ("x86/domctl: Make XEN_DOMCTL_set_address_size
    singleshot", Xen 4.9, 2016), it was possible for domains to switch to being
    compat, and back again.  Since then however, becoming compat is a singleton
    action that can't be undone.
    
    From the context it's clear to see the is_pv_32bit_domain() check is
    redundant, and from the singleton nature and being the only place setting
    physaddr_bitsize, there's no need to check it for being 0.
    
    No functional change.
    
    Co-developed-by: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/include/asm/mm.h |  1 -
 xen/arch/x86/pv/domain.c      |  6 +++++-
 xen/arch/x86/x86_64/mm.c      | 13 -------------
 3 files changed, 5 insertions(+), 15 deletions(-)

diff --git a/xen/arch/x86/include/asm/mm.h b/xen/arch/x86/include/asm/mm.h
index 17ca6666a3..9438f5ea01 100644
--- a/xen/arch/x86/include/asm/mm.h
+++ b/xen/arch/x86/include/asm/mm.h
@@ -619,7 +619,6 @@ void __iomem *ioremap_wc(paddr_t pa, size_t len);
 
 extern int memory_add(unsigned long spfn, unsigned long epfn, unsigned int 
pxm);
 
-void domain_set_alloc_bitsize(struct domain *d);
 unsigned int domain_clamp_alloc_bitsize(struct domain *d, unsigned int bits);
 #define domain_clamp_alloc_bitsize(d, bits) domain_clamp_alloc_bitsize(d, bits)
 
diff --git a/xen/arch/x86/pv/domain.c b/xen/arch/x86/pv/domain.c
index 9c4785c187..11db6a6d83 100644
--- a/xen/arch/x86/pv/domain.c
+++ b/xen/arch/x86/pv/domain.c
@@ -254,7 +254,11 @@ int switch_compat(struct domain *d)
             goto undo_and_fail;
     }
 
-    domain_set_alloc_bitsize(d);
+    if ( MACH2PHYS_COMPAT_NR_ENTRIES(d) < max_page )
+        d->arch.physaddr_bitsize =
+            /* 2^n entries can be contained in guest's p2m mapping space */
+            fls(MACH2PHYS_COMPAT_NR_ENTRIES(d)) - 1 + PAGE_SHIFT;
+
     recalculate_cpuid_policy(d);
 
     d->arch.x87_fip_width = 4;
diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index d4e6a9c0a2..42fd4fe4e9 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -1119,19 +1119,6 @@ unmap:
     return ret;
 }
 
-void domain_set_alloc_bitsize(struct domain *d)
-{
-    if ( !is_pv_32bit_domain(d) ||
-         (MACH2PHYS_COMPAT_NR_ENTRIES(d) >= max_page) ||
-         d->arch.physaddr_bitsize > 0 )
-        return;
-    d->arch.physaddr_bitsize =
-        /* 2^n entries can be contained in guest's p2m mapping space */
-        fls(MACH2PHYS_COMPAT_NR_ENTRIES(d)) - 1
-        /* 2^n pages -> 2^(n+PAGE_SHIFT) bits */
-        + PAGE_SHIFT;
-}
-
 unsigned int domain_clamp_alloc_bitsize(struct domain *d, unsigned int bits)
 {
     if ( (d == NULL) || (d->arch.physaddr_bitsize == 0) )
--
generated by git-patchbot for /home/xen/git/xen.git#staging