From ce53053ce378c21e7ffc45241fd67d6ee79daa2b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 19 Nov 2017 17:47:33 -0500 Subject: kvm: switch get_user_page_nowait() to get_user_pages_unlocked() ... and fold into the sole caller, unifying async and non-async cases Signed-off-by: Al Viro --- virt/kvm/kvm_main.c | 43 ++++++++++++------------------------------- 1 file changed, 12 insertions(+), 31 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f169ecc4f2e8..ae4985bc8a8a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1314,17 +1314,6 @@ unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *w return gfn_to_hva_memslot_prot(slot, gfn, writable); } -static int get_user_page_nowait(unsigned long start, int write, - struct page **page) -{ - int flags = FOLL_NOWAIT | FOLL_HWPOISON; - - if (write) - flags |= FOLL_WRITE; - - return get_user_pages(start, 1, flags, page, NULL); -} - static inline int check_user_page_hwpoison(unsigned long addr) { int rc, flags = FOLL_HWPOISON | FOLL_WRITE; @@ -1373,7 +1362,8 @@ static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async, static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, bool *writable, kvm_pfn_t *pfn) { - struct page *page[1]; + unsigned int flags = FOLL_HWPOISON; + struct page *page; int npages = 0; might_sleep(); @@ -1381,35 +1371,26 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, if (writable) *writable = write_fault; - if (async) { - down_read(¤t->mm->mmap_sem); - npages = get_user_page_nowait(addr, write_fault, page); - up_read(¤t->mm->mmap_sem); - } else { - unsigned int flags = FOLL_HWPOISON; - - if (write_fault) - flags |= FOLL_WRITE; + if (write_fault) + flags |= FOLL_WRITE; + if (async) + flags |= FOLL_NOWAIT; - npages = get_user_pages_unlocked(addr, 1, page, flags); - } + npages = get_user_pages_unlocked(addr, 1, &page, flags); if (npages != 1) return npages; /* map read fault as writable if possible */ if (unlikely(!write_fault) && writable) { - struct page *wpage[1]; + struct page *wpage; - npages = __get_user_pages_fast(addr, 1, 1, wpage); - if (npages == 1) { + if (__get_user_pages_fast(addr, 1, 1, &wpage) == 1) { *writable = true; - put_page(page[0]); - page[0] = wpage[0]; + put_page(page); + page = wpage; } - - npages = 1; } - *pfn = page_to_pfn(page[0]); + *pfn = page_to_pfn(page); return npages; } -- cgit v1.2.3-59-g8ed1b