From patchwork Wed Apr 26 19:58:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anisse Astier X-Patchwork-Id: 677587 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11AFEC77B7E for ; Wed, 26 Apr 2023 19:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234837AbjDZT7L (ORCPT ); Wed, 26 Apr 2023 15:59:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233709AbjDZT7K (ORCPT ); Wed, 26 Apr 2023 15:59:10 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CBD5D2; Wed, 26 Apr 2023 12:59:09 -0700 (PDT) Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.west.internal (Postfix) with ESMTP id A8CD73200935; Wed, 26 Apr 2023 15:59:07 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Wed, 26 Apr 2023 15:59:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=astier.eu; h=cc :cc:content-transfer-encoding:content-type:date:date:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to; s=fm3; t=1682539147; x=1682625547; bh=+dM23Sbs2y Ywhw7ZQN+S1+KilA+WqOVJpT49zdDKWHk=; b=YNDWsyZ/Hw8roX6n/sADtUMRsV 7bOz4+7t2k29yB3lHczJzK4PmHvYlHot1eZO9PeU0JsItDfVINkozr/kiGjMU2IE sOyNg9LKvYgYdonmJw6k8x9u2Yqm1FAt67o6+jFwx6ycgPp2LW5zkPFjP9nDGbtW VAiSgNAObFF21GdHhmJSdbxJl1am4QrQ31pVKKu9Wu9ZGSjHXFagV/PXDmbBUcpT usDtPpAGsWJt+mOGFIL+9QX4PRrPiv0LO3bjX06eBkg+1EZVxeSnAhUrHsEjnkV8 jJv7S87otJvveFC2yPgEOa0iYkD1n2d7aOpHpMpWvvftX610ISjVC1sMVdcQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1682539147; x=1682625547; bh=+dM23Sbs2yYwh w7ZQN+S1+KilA+WqOVJpT49zdDKWHk=; b=Xkj3o6g5TYSLEM92tuOJXKICLKuNI gglmM1y4Z5D5jm7ye6esp4yXTkS9YxvraFrCw864n9ByUZ7QvzOLew5+2N7Z2Gtq rJHB4L7ouMqFkraS41Hyjagg0Iutuvcu7iIqRNDxuZIJPwRLZ7QlHbBazYjMaq5h WBMK3FcXawYMksgwrUgyDzNswObOb1ewnTp+8OFMObigMO42SwJ1IT+Wqr6V0IBK 5nNPXhm7oxkSyyzZShE7fQMT16QYFeNGYBoA7hDUlWyoW9kthwFEhPV9bzB1QzFe RH+PHfRndcfvwAQEJYWvIH6I7w1qBeIV7Jw/BVDZsPJKpf6r7JsTpiyZg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvhedrfedugedgudeggecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvfevufffkffoggfgsedtkeertdertddtnecuhfhrohhmpeetnhhishhs vgcutehsthhivghruceorghnihhsshgvsegrshhtihgvrhdrvghuqeenucggtffrrghtth gvrhhnpedtfffhleekhefhheeftedthfejgfffvddtleehffdtjefftdehkeetfeefieel keenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegrnh hishhsvgesrghsthhivghrrdgvuh X-ME-Proxy: Feedback-ID: iccec46d4:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 26 Apr 2023 15:59:03 -0400 (EDT) From: Anisse Astier To: linux-efi@vger.kernel.org Cc: Ard Biesheuvel , Johan Hovold , Darren Hart , Andy Shevchenko , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Jeremy Kerr , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Anisse Astier , Anisse Astier Subject: [PATCH] efivarfs: expose used and total size Date: Wed, 26 Apr 2023 21:58:53 +0200 Message-Id: <20230426195853.633233-1-anisse@astier.eu> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Anisse Astier When writing variables, one might get errors with no other message on why it fails. Being able to see how much is used by EFI variables helps analyzing such issues. Since this is not a conventionnal filesystem, block size is intentionnally set to 1 instead of PAGE_SIZE. x86 quirks of reserved size are taken into account and available and free size can be different, further helping debugging space issues. Signed-off-by: Anisse Astier --- Notes: Patch isn't split per subsystem intentionally, for better understanding of intent; split could be trivial in a later version. I'm not sure whether statfs(2) should return an error if the efi request fails; I think it could be ignored with maybe a WARN_ONCE; which would be close to the current behaviour. Regards, Anisse --- arch/x86/platform/efi/quirks.c | 8 ++++++++ drivers/firmware/efi/efi.c | 1 + drivers/firmware/efi/vars.c | 12 ++++++++++++ fs/efivarfs/super.c | 26 +++++++++++++++++++++++++- include/linux/efi.h | 10 ++++++++++ 5 files changed, 56 insertions(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index b0b848d6933a..587fa51230e2 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -114,6 +114,14 @@ void efi_delete_dummy_variable(void) EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL); } +u64 efi_reserved_space(void) +{ + if (efi_no_storage_paranoia) + return 0; + return EFI_MIN_RESERVE; +} +EXPORT_SYMBOL_GPL(efi_reserved_space); + /* * In the nonblocking case we do not attempt to perform garbage * collection if we do not have enough free space. Rather, we do the diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index abeff7dc0b58..d0dfa007bffc 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -211,6 +211,7 @@ static int generic_ops_register(void) generic_ops.get_variable = efi.get_variable; generic_ops.get_next_variable = efi.get_next_variable; generic_ops.query_variable_store = efi_query_variable_store; + generic_ops.query_variable_info = efi.query_variable_info; if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) { generic_ops.set_variable = efi.set_variable; diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index bd75b87f5fc1..c5382d5c3073 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -245,3 +245,15 @@ efi_status_t efivar_set_variable(efi_char16_t *name, efi_guid_t *vendor, return status; } EXPORT_SYMBOL_NS_GPL(efivar_set_variable, EFIVAR); + +efi_status_t efivar_query_variable_info(u32 attr, + u64 *storage_space, + u64 *remaining_space, + u64 *max_variable_size) +{ + if (!__efivars->ops->query_variable_info) + return EFI_UNSUPPORTED; + return __efivars->ops->query_variable_info(attr, storage_space, + remaining_space, max_variable_size); +} +EXPORT_SYMBOL_NS_GPL(efivar_query_variable_info, EFIVAR); diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index 482d612b716b..064bfc0243c9 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -13,6 +13,7 @@ #include #include #include +#include #include "internal.h" @@ -23,8 +24,31 @@ static void efivarfs_evict_inode(struct inode *inode) clear_inode(inode); } +static int efivarfs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + u64 storage_space, remaining_space, max_variable_size; + efi_status_t status; + const u32 attr = (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS); + + buf->f_type = dentry->d_sb->s_magic; + buf->f_bsize = 1; + buf->f_namelen = NAME_MAX; + + status = efivar_query_variable_info(attr, &storage_space, &remaining_space, + &max_variable_size); + if (status != EFI_SUCCESS) + return efi_status_to_err(status); + buf->f_blocks = storage_space; + buf->f_bfree = remaining_space; + if (remaining_space > efi_reserved_space()) + buf->f_bavail = remaining_space - efi_reserved_space(); + else + buf->f_bavail = 0; + return 0; +} static const struct super_operations efivarfs_ops = { - .statfs = simple_statfs, + .statfs = efivarfs_statfs, .drop_inode = generic_delete_inode, .evict_inode = efivarfs_evict_inode, }; diff --git a/include/linux/efi.h b/include/linux/efi.h index 7aa62c92185f..d2b686191870 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -703,6 +703,7 @@ static inline void efi_enter_virtual_mode (void) {} extern efi_status_t efi_query_variable_store(u32 attributes, unsigned long size, bool nonblocking); +extern u64 efi_reserved_space(void); #else static inline efi_status_t efi_query_variable_store(u32 attributes, @@ -711,6 +712,10 @@ static inline efi_status_t efi_query_variable_store(u32 attributes, { return EFI_SUCCESS; } +static inline u64 efi_reserved_space(void) +{ + return 0; +} #endif extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr); @@ -1042,6 +1047,7 @@ struct efivar_operations { efi_set_variable_t *set_variable; efi_set_variable_t *set_variable_nonblocking; efi_query_variable_store_t *query_variable_store; + efi_query_variable_info_t *query_variable_info; }; struct efivars { @@ -1087,6 +1093,10 @@ efi_status_t efivar_set_variable_locked(efi_char16_t *name, efi_guid_t *vendor, efi_status_t efivar_set_variable(efi_char16_t *name, efi_guid_t *vendor, u32 attr, unsigned long data_size, void *data); +efi_status_t efivar_query_variable_info(u32 attr, u64 *storage_space, + u64 *remaining_space, + u64 *max_variable_size); + #if IS_ENABLED(CONFIG_EFI_CAPSULE_LOADER) extern bool efi_capsule_pending(int *reset_type);