From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tiejun Chen Subject: [v6][PATCH 1/2] xen:x86:mm:p2m: introduce set_identity_p2m_entry Date: Wed, 30 Jul 2014 09:26:05 +0800 Message-ID: <1406683567-11600-1-git-send-email-tiejun.chen@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: JBeulich@suse.com, yang.z.zhang@intel.com, kevin.tian@intel.com Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org Its used conveniently to create RMRR mapping in shared EPT case. Signed-off-by: Tiejun Chen --- xen/arch/x86/mm/p2m.c | 29 +++++++++++++++++++++++++++++ xen/include/asm-x86/p2m.h | 3 +++ 2 files changed, 32 insertions(+) v6: * Refactor set_identity_p2m_entry to make sense v5: * Rename this function as set_identity_p2m_entry() * Get mfn directly inside set_identity_p2m_entry() v4: * new patch to combine get and set together to create RMRR mapping. diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index 642ec28..06bed7a 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -858,6 +858,35 @@ int set_mmio_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn) return set_typed_p2m_entry(d, gfn, mfn, p2m_mmio_direct); } +int set_identity_p2m_entry(struct domain *d, unsigned long gfn) +{ + p2m_type_t p2mt; + p2m_access_t a; + mfn_t mfn; + struct p2m_domain *p2m = p2m_get_hostp2m(d); + int ret = -EBUSY; + + gfn_lock(p2m, gfn, 0); + + mfn = p2m->get_entry(p2m, gfn, &p2mt, &a, 0, NULL); + + if ( !mfn_valid(mfn) ) + ret = p2m_set_entry(p2m, gfn, _mfn(gfn), PAGE_ORDER_4K, p2m_mmio_direct, + p2m_access_rw); + else if ( mfn_x(mfn) == gfn && + p2mt == p2m_mmio_direct && + a == p2m_access_rw ) + ret = 0; + else + printk(XENLOG_G_WARNING + "Cannot identity map d%d:%lx, already mapped to %lx.\n", + d->domain_id, gfn, mfn_x(mfn)); + + gfn_unlock(p2m, gfn, 0); + + return ret; +} + /* Returns: 0 for success, -errno for failure */ int clear_mmio_p2m_entry(struct domain *d, unsigned long gfn) { diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h index 0ddbadb..d130f9a 100644 --- a/xen/include/asm-x86/p2m.h +++ b/xen/include/asm-x86/p2m.h @@ -536,6 +536,9 @@ int p2m_is_logdirty_range(struct p2m_domain *, unsigned long start, int set_mmio_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn); int clear_mmio_p2m_entry(struct domain *d, unsigned long gfn); +/* Set identity addresses in the p2m table (for pass-through) */ +int set_identity_p2m_entry(struct domain *d, unsigned long gfn); + /* Add foreign mapping to the guest's p2m table. */ int p2m_add_foreign(struct domain *tdom, unsigned long fgfn, unsigned long gpfn, domid_t foreign_domid); -- 1.9.1