From patchwork Tue Feb 4 12:05:39 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= X-Patchwork-Id: 13959052 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 65250C02194 for ; Tue, 4 Feb 2025 12:18:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=JAOVW8H/jmZUurJoSsBqrn657OqlOYnQawrkcGFYNtg=; b=K8ZbfAQO78gDYz3XmMhLPMlOzd OdrGbYxcoubeOnE2Jx3zeJ3l4lzrNWBoUsj9R0ZpOwXavNDUUvLFpOOMQ6vN88wNfDQQ3sIxzXdxF tyjX4QH83I4/a86TVGPNmoVkaXwvvUaR39TC2UveLvM61lrBe2Ve5h1oCU0nAaWqaeOPnwqy5EToR tCepsgxKYz5uHw01aGql7uGWrtQ1065JVqZgbGfFp9yUiU7OUVL+vVzz063ABfzPVtYYZvZY9rXdg O6q/WeAml/b6D/WO2I6yyKc8815/oiyzxg4Zd4DFjRw6SjOymefgrg3BXWnbF4FmpMrOCLB6R/wuN dCe86cBA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tfHt4-00000000OwP-33jm; Tue, 04 Feb 2025 12:18:42 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tfHgz-00000000LLp-3YDk; Tue, 04 Feb 2025 12:06:16 +0000 From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1738670769; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JAOVW8H/jmZUurJoSsBqrn657OqlOYnQawrkcGFYNtg=; b=oEXuPSFJw3vOyfHksK8gvKbLrFFkz0qxmosTiczrxSReVtw/8Ch595sZtd44xx2JO9t/e6 HIgrZyL10KywpVcEq5/M7tlolFDd3E/UBCv2USw56HpQP9iQuPRJPc5cgMmRcecQPAWUgU BfNGUOwJxXyKERem6dKoQSgxYlWE5pF+AdZuEFLEIawoURCs/ls98rDZE3JSP828TH6Kbv LzzqiR/Fu2Wo/uifYNdGYju1bziKAy6XnLpBi+I9QBPRDLqlnhF7T1fc3T3b+vRwZxk+L6 zZk8QFrgh72taIf2qRAvrIDKsQWI4B/eg+pDubW5ET5z5JUZXmAvpQpNcr4DyQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1738670769; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JAOVW8H/jmZUurJoSsBqrn657OqlOYnQawrkcGFYNtg=; b=JWZ2VRs+cdR71gOVuHVaODZFDW60BiYqFTQqa41rwfR9c+wkqnBvPnlxsY3xKO44U64EDJ Y8GIGe1DjznazdBQ== Date: Tue, 04 Feb 2025 13:05:39 +0100 Subject: [PATCH v3 07/18] vdso: Add generic architecture-specific data storage MIME-Version: 1.0 Message-Id: <20250204-vdso-store-rng-v3-7-13a4669dfc8c@linutronix.de> References: <20250204-vdso-store-rng-v3-0-13a4669dfc8c@linutronix.de> In-Reply-To: <20250204-vdso-store-rng-v3-0-13a4669dfc8c@linutronix.de> To: "James E.J. Bottomley" , Helge Deller , Andy Lutomirski , Thomas Gleixner , Vincenzo Frascino , Anna-Maria Behnsen , Frederic Weisbecker , Andrew Morton , Catalin Marinas , Will Deacon , Theodore Ts'o , "Jason A. Donenfeld" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Huacai Chen , WANG Xuerui , Russell King , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Bogendoerfer , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Madhavan Srinivasan , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Arnd Bergmann , Guo Ren Cc: linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, loongarch@lists.linux.dev, linux-s390@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, Nam Cao , =?utf-8?q?Thom?= =?utf-8?q?as_Wei=C3=9Fschuh?= , linux-csky@vger.kernel.org X-Developer-Signature: v=1; a=ed25519-sha256; t=1738670761; l=4823; i=thomas.weissschuh@linutronix.de; s=20240209; h=from:subject:message-id; bh=hqYzcPXwdjmayHj4U7VVt9y+emzZQxkmpVtEmg40Qdg=; b=eT418J3Cm/UT46u3wK7qwnCsDxT/tmxu49usXJsjpoj8C3SYD1MzSQXHqYZhez8ul/Cc3g2m6 Bz3DxyokUDfAL/pz7NPVpBrIIDX51xI7KrQDJQFryKy2sECT03IsTYB X-Developer-Key: i=thomas.weissschuh@linutronix.de; a=ed25519; pk=pfvxvpFUDJV2h2nY0FidLUml22uGLSjByFbM6aqQQws= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250204_040614_214572_BE558AF8 X-CRM114-Status: GOOD ( 15.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Some architectures need to architecture-specific data to the vDSO. Enable the generic vDSO storage mechanism to both store and map this data. Some architectures require more than a single page, like LoongArch, so prepare for that usecase, too. Signed-off-by: Thomas Weißschuh --- arch/Kconfig | 4 ++++ include/vdso/datapage.h | 25 +++++++++++++++++++++++++ lib/vdso/datastore.c | 14 ++++++++++++++ 3 files changed, 43 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index b8a4ff36558228240080a5677f702d37f4f8d547..9f6eb09ef12d76e755c0fd2df71ba703c251052f 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1584,6 +1584,10 @@ config HAVE_SPARSE_SYSCALL_NR entries at 4000, 5000 and 6000 locations. This option turns on syscall related optimizations for a given architecture. +config ARCH_HAS_VDSO_ARCH_DATA + depends on GENERIC_VDSO_DATA_STORE + bool + config ARCH_HAS_VDSO_TIME_DATA bool diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h index 7dbc8797e3b8923c06f4b6b34790766e68b2abd2..46658b39c28250e977f5a3454224c3ed0fb4c81d 100644 --- a/include/vdso/datapage.h +++ b/include/vdso/datapage.h @@ -9,11 +9,13 @@ #include #include +#include #include #include #include #include #include +#include #include #include #include @@ -25,6 +27,15 @@ struct arch_vdso_time_data {}; #endif +#if defined(CONFIG_ARCH_HAS_VDSO_ARCH_DATA) +#include +#elif defined(CONFIG_GENERIC_VDSO_DATA_STORE) +struct vdso_arch_data { + /* Needed for the generic code, never actually used at runtime */ + char __unused; +}; +#endif + #define VDSO_BASES (CLOCK_TAI + 1) #define VDSO_HRES (BIT(CLOCK_REALTIME) | \ BIT(CLOCK_MONOTONIC) | \ @@ -145,9 +156,11 @@ extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden"))) #else extern struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden"))); extern struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden"))); +extern struct vdso_arch_data vdso_u_arch_data __attribute__((visibility("hidden"))); extern struct vdso_time_data *vdso_k_time_data; extern struct vdso_rng_data *vdso_k_rng_data; +extern struct vdso_arch_data *vdso_k_arch_data; #endif /** @@ -160,10 +173,15 @@ union vdso_data_store { #ifdef CONFIG_GENERIC_VDSO_DATA_STORE +#define VDSO_ARCH_DATA_SIZE ALIGN(sizeof(struct vdso_arch_data), PAGE_SIZE) +#define VDSO_ARCH_DATA_PAGES (VDSO_ARCH_DATA_SIZE >> PAGE_SHIFT) + enum vdso_pages { VDSO_TIME_PAGE_OFFSET, VDSO_TIMENS_PAGE_OFFSET, VDSO_RNG_PAGE_OFFSET, + VDSO_ARCH_PAGES_START, + VDSO_ARCH_PAGES_END = VDSO_ARCH_PAGES_START + VDSO_ARCH_DATA_PAGES - 1, VDSO_NR_PAGES }; @@ -193,10 +211,17 @@ enum vdso_pages { #define __vdso_u_rng_data #endif +#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA +#define __vdso_u_arch_data PROVIDE(vdso_u_arch_data = vdso_u_data + 3 * PAGE_SIZE); +#else +#define __vdso_u_arch_data +#endif + #define VDSO_VVAR_SYMS \ PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \ PROVIDE(vdso_u_time_data = vdso_u_data); \ __vdso_u_rng_data \ + __vdso_u_arch_data \ #endif /* !__ASSEMBLY__ */ diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c index 9260b00dc8520af109bd9dd05ac7f7504eafbea0..0959d62d78586ef458eb5f7c1e152f6b5d4cbf85 100644 --- a/lib/vdso/datastore.c +++ b/lib/vdso/datastore.c @@ -26,6 +26,14 @@ struct vdso_rng_data *vdso_k_rng_data = &vdso_rng_data_store.data; static_assert(sizeof(vdso_rng_data_store) == PAGE_SIZE); #endif /* CONFIG_VDSO_GETRANDOM */ +#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA +static union { + struct vdso_arch_data data; + u8 page[VDSO_ARCH_DATA_SIZE]; +} vdso_arch_data_store __page_aligned_data; +struct vdso_arch_data *vdso_k_arch_data = &vdso_arch_data_store.data; +#endif /* CONFIG_ARCH_HAS_VDSO_ARCH_DATA */ + static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, struct vm_area_struct *vma, struct vm_fault *vmf) { @@ -67,6 +75,12 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, return VM_FAULT_SIGBUS; pfn = __phys_to_pfn(__pa_symbol(vdso_k_rng_data)); break; + case VDSO_ARCH_PAGES_START ... VDSO_ARCH_PAGES_END: + if (!IS_ENABLED(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)) + return VM_FAULT_SIGBUS; + pfn = __phys_to_pfn(__pa_symbol(vdso_k_arch_data)) + + vmf->pgoff - VDSO_ARCH_PAGES_START; + break; default: return VM_FAULT_SIGBUS; }