On Mon, Sep 16, 2019 at 01:18:02PM +0300, Jarkko Sakkinen wrote:
> Since __sgx_encl_eldu() and __sgx_encl_ewb() pin the backing storage in the
> same way, consolidate this to sgx_encl_get_backing() replacing
> sgx_encl_get_backing_page().
>
> Cc: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> Cc: Shay Katz-zamir <shay.katz-zamir@xxxxxxxxx>
> Cc: Serge Ayoun <serge.ayoun@xxxxxxxxx>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> ---
> arch/x86/kernel/cpu/sgx/encl.c | 86 +++++++++++++++++++------------
> arch/x86/kernel/cpu/sgx/encl.h | 20 +++----
> arch/x86/kernel/cpu/sgx/reclaim.c | 39 ++++----------
> 3 files changed, 71 insertions(+), 74 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
> index 66762b9c1517..a71414ce05b1 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.c
> +++ b/arch/x86/kernel/cpu/sgx/encl.c
> @@ -17,11 +17,8 @@ static int __sgx_encl_eldu(struct sgx_encl_page *encl_page,
> unsigned long va_offset = SGX_ENCL_PAGE_VA_OFFSET(encl_page);
> struct sgx_encl *encl = encl_page->encl;
> struct sgx_pageinfo pginfo;
> - unsigned long pcmd_offset;
> - struct page *backing;
> + struct sgx_backing b;
> pgoff_t page_index;
> - pgoff_t pcmd_index;
> - struct page *pcmd;
> int ret;
>
> if (secs_page)
> @@ -29,24 +26,14 @@ static int __sgx_encl_eldu(struct sgx_encl_page *encl_page,
> else
> page_index = PFN_DOWN(encl->size);
>
> - pcmd_index = sgx_pcmd_index(encl, page_index);
> - pcmd_offset = sgx_pcmd_offset(page_index);
> -
> - backing = sgx_encl_get_backing_page(encl, page_index);
> - if (IS_ERR(backing)) {
> - ret = PTR_ERR(backing);
> - goto err_backing;
> - }
> -
> - pcmd = sgx_encl_get_backing_page(encl, pcmd_index);
> - if (IS_ERR(pcmd)) {
> - ret = PTR_ERR(pcmd);
> - goto err_pcmd;
> - }
> + ret = sgx_encl_get_backing(encl, page_index, &b);
> + if (ret)
> + return ret;
>
> pginfo.addr = SGX_ENCL_PAGE_ADDR(encl_page);
> - pginfo.contents = (unsigned long)kmap_atomic(backing);
> - pginfo.metadata = (unsigned long)kmap_atomic(pcmd) + pcmd_offset;
> + pginfo.contents = (unsigned long)kmap_atomic(b.contents);
> + pginfo.metadata = (unsigned long)kmap_atomic(b.pcmd) +
> + b.pcmd_offset;
>
> if (secs_page)
> pginfo.secs = (u64)sgx_epc_addr(secs_page);
> @@ -62,15 +49,12 @@ static int __sgx_encl_eldu(struct sgx_encl_page *encl_page,
> ret = -EFAULT;
> }
>
> - kunmap_atomic((void *)(unsigned long)(pginfo.metadata - pcmd_offset));
> + kunmap_atomic((void *)(unsigned long)(pginfo.metadata - b.pcmd_offset));
> kunmap_atomic((void *)(unsigned long)pginfo.contents);
>
> - put_page(pcmd);
> + put_page(b.pcmd);
> + put_page(b.contents);
If we're going to have sgx_encl_get_backing(), it should be paired with
sgx_encl_put_backing(), e.g. it's not immediately obvious whose doing the
"get page" corresponding to the put_page() calls.
