From c3798062f100c3e1d4ae1241bc536f3b1f28a6ca Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 27 Aug 2010 13:42:04 -0700 Subject: [PATCH] xen: add return value to set_phys_to_machine() set_phys_to_machine() can return false on failure, which means a memory allocation failure for the p2m structure. It can only fail if setting the mfn for a pfn in previously unused address space. It is guaranteed to succeed if you're setting a mapping to INVALID_P2M_ENTRY or updating the mfn for an existing pfn. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/include/asm/xen/page.h | 2 +- arch/x86/xen/mmu.c | 13 ++++++++----- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index bf5f7d32bd08..e40ca6e67bb5 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -37,7 +37,7 @@ typedef struct xpaddr { extern unsigned long get_phys_to_machine(unsigned long pfn); -extern void set_phys_to_machine(unsigned long pfn, unsigned long mfn); +extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn); static inline unsigned long pfn_to_mfn(unsigned long pfn) { diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index d4c7265cf0a0..b96513437236 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -282,7 +282,7 @@ static void p2m_init(unsigned long *p2m) */ void xen_build_mfn_list_list(void) { - unsigned pfn, i; + unsigned pfn; /* Pre-initialize p2m_top_mfn to be completely missing */ if (p2m_top_mfn == NULL) { @@ -496,19 +496,22 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn) return true; } -void set_phys_to_machine(unsigned long pfn, unsigned long mfn) +bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) { if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) { BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); - return; + return true; } if (unlikely(!__set_phys_to_machine(pfn, mfn))) { - WARN(!alloc_p2m(pfn), "Can't allocate p2m for %lx, %lx", pfn, mfn); + if (!alloc_p2m(pfn)) + return false; if (!__set_phys_to_machine(pfn, mfn)) - BUG(); + return false; } + + return true; } unsigned long arbitrary_virt_to_mfn(void *vaddr)