From patchwork Thu Dec 28 10:51:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi-De Wu X-Patchwork-Id: 759056 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 39348107AD; Thu, 28 Dec 2023 10:52:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mediatek.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mediatek.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="Wg+XfGRo" X-UUID: 1ce77fa4a56f11eea2298b7352fd921d-20231228 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=3RowJutghvCCzUPws4AkIvMiK0uJIdrw9LkRmzUdaIU=; b=Wg+XfGRoRHahwHlfyav/s/+J35GgX+A3hF6CvHYQVjgVujT/8xJsMRp6vVskN3obQzkqkf6tm+zBQSmCezFS8csaHALVyXtYbBOcl23Vgc7PPlTjWD+ira9buipLtijNDwkbWtjVASk37YHbPqnhdrXFdGk7Kp9NuxD7wdSMDho=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.35, REQID:58727c6c-be8b-4846-8320-7a889a754f48, IP:0, U RL:0,TC:0,Content:-25,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-25 X-CID-META: VersionHash:5d391d7, CLOUDID:cc694382-8d4f-477b-89d2-1e3bdbef96d1, B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:11|1,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR: NO,DKR:0,DKP:0,BRR:0,BRE:0 X-CID-BVR: 0 X-CID-BAS: 0,_,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULN X-UUID: 1ce77fa4a56f11eea2298b7352fd921d-20231228 Received: from mtkmbs13n1.mediatek.inc [(172.21.101.193)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 939322484; Thu, 28 Dec 2023 18:51:53 +0800 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by mtkmbs13n2.mediatek.inc (172.21.101.108) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Thu, 28 Dec 2023 18:51:52 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Thu, 28 Dec 2023 18:51:52 +0800 From: Yi-De Wu To: Yingshiuan Pan , Ze-Yu Wang , Yi-De Wu , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Corbet , Catalin Marinas , Wihl Deacon , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Richard Cochran , Matthias Brugger , AngeloGioacchino Del Regno CC: , , , , , , , David Bradil , Trilok Soni , Jade Shih , Ivan Tseng , My Chuang , Shawn Hsiao , PeiLun Suei , Liju Chen , Willix Yeh , Kevenny Hsieh Subject: [PATCH v8 11/20] virt: geniezone: Add ioeventfd support Date: Thu, 28 Dec 2023 18:51:38 +0800 Message-ID: <20231228105147.13752-12-yi-de.wu@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20231228105147.13752-1-yi-de.wu@mediatek.com> References: <20231228105147.13752-1-yi-de.wu@mediatek.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MTK: N From: "Yingshiuan Pan" Ioeventfd leverages eventfd to provide asynchronous notification mechanism for VMM. VMM can register a mmio address and bind with an eventfd. Once a mmio trap occurs on this registered region, its corresponding eventfd will be notified. Signed-off-by: Yingshiuan Pan Signed-off-by: Liju Chen Signed-off-by: Yi-De Wu --- drivers/virt/geniezone/Makefile | 3 +- drivers/virt/geniezone/gzvm_ioeventfd.c | 276 ++++++++++++++++++++++++ drivers/virt/geniezone/gzvm_vcpu.c | 27 ++- drivers/virt/geniezone/gzvm_vm.c | 17 ++ include/linux/gzvm_drv.h | 12 ++ include/uapi/linux/gzvm.h | 25 +++ 6 files changed, 358 insertions(+), 2 deletions(-) create mode 100644 drivers/virt/geniezone/gzvm_ioeventfd.c diff --git a/drivers/virt/geniezone/Makefile b/drivers/virt/geniezone/Makefile index cebe5ad53f41..9956f4891df2 100644 --- a/drivers/virt/geniezone/Makefile +++ b/drivers/virt/geniezone/Makefile @@ -8,4 +8,5 @@ GZVM_DIR ?= ../../../drivers/virt/geniezone gzvm-y := $(GZVM_DIR)/gzvm_main.o $(GZVM_DIR)/gzvm_vm.o \ $(GZVM_DIR)/gzvm_mmu.o $(GZVM_DIR)/gzvm_vcpu.o \ - $(GZVM_DIR)/gzvm_irqfd.o + $(GZVM_DIR)/gzvm_irqfd.o $(GZVM_DIR)/gzvm_ioeventfd.o + diff --git a/drivers/virt/geniezone/gzvm_ioeventfd.c b/drivers/virt/geniezone/gzvm_ioeventfd.c new file mode 100644 index 000000000000..542b414485e3 --- /dev/null +++ b/drivers/virt/geniezone/gzvm_ioeventfd.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2023 MediaTek Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct gzvm_ioevent { + struct list_head list; + __u64 addr; + __u32 len; + struct eventfd_ctx *evt_ctx; + __u64 datamatch; + bool wildcard; +}; + +/** + * ioeventfd_check_collision() - Check collison assumes gzvm->slots_lock held. + * @gzvm: Pointer to gzvm. + * @p: Pointer to gzvm_ioevent. + * + * Return: + * * true - collison found + * * false - no collison + */ +static bool ioeventfd_check_collision(struct gzvm *gzvm, struct gzvm_ioevent *p) +{ + struct gzvm_ioevent *_p; + + list_for_each_entry(_p, &gzvm->ioevents, list) { + if (_p->addr == p->addr && + (!_p->len || !p->len || + (_p->len == p->len && + (_p->wildcard || p->wildcard || + _p->datamatch == p->datamatch)))) + return true; + if (p->addr >= _p->addr && p->addr < _p->addr + _p->len) + return true; + } + + return false; +} + +static void gzvm_ioevent_release(struct gzvm_ioevent *p) +{ + eventfd_ctx_put(p->evt_ctx); + list_del(&p->list); + kfree(p); +} + +static bool gzvm_ioevent_in_range(struct gzvm_ioevent *p, __u64 addr, int len, + const void *val) +{ + u64 _val; + + if (addr != p->addr) + /* address must be precise for a hit */ + return false; + + if (!p->len) + /* length = 0 means only look at the address, so always a hit */ + return true; + + if (len != p->len) + /* address-range must be precise for a hit */ + return false; + + if (p->wildcard) + /* all else equal, wildcard is always a hit */ + return true; + + /* otherwise, we have to actually compare the data */ + + WARN_ON_ONCE(!IS_ALIGNED((unsigned long)val, len)); + + switch (len) { + case 1: + _val = *(u8 *)val; + break; + case 2: + _val = *(u16 *)val; + break; + case 4: + _val = *(u32 *)val; + break; + case 8: + _val = *(u64 *)val; + break; + default: + return false; + } + + return _val == p->datamatch; +} + +static int gzvm_deassign_ioeventfd(struct gzvm *gzvm, + struct gzvm_ioeventfd *args) +{ + struct gzvm_ioevent *p, *tmp; + struct eventfd_ctx *evt_ctx; + int ret = -ENOENT; + bool wildcard; + + evt_ctx = eventfd_ctx_fdget(args->fd); + if (IS_ERR(evt_ctx)) + return PTR_ERR(evt_ctx); + + wildcard = !(args->flags & GZVM_IOEVENTFD_FLAG_DATAMATCH); + + mutex_lock(&gzvm->lock); + + list_for_each_entry_safe(p, tmp, &gzvm->ioevents, list) { + if (p->evt_ctx != evt_ctx || + p->addr != args->addr || + p->len != args->len || + p->wildcard != wildcard) + continue; + + if (!p->wildcard && p->datamatch != args->datamatch) + continue; + + gzvm_ioevent_release(p); + ret = 0; + break; + } + + mutex_unlock(&gzvm->lock); + + /* got in the front of this function */ + eventfd_ctx_put(evt_ctx); + + return ret; +} + +static int gzvm_assign_ioeventfd(struct gzvm *gzvm, struct gzvm_ioeventfd *args) +{ + struct eventfd_ctx *evt_ctx; + struct gzvm_ioevent *evt; + int ret; + + evt_ctx = eventfd_ctx_fdget(args->fd); + if (IS_ERR(evt_ctx)) + return PTR_ERR(evt_ctx); + + evt = kmalloc(sizeof(*evt), GFP_KERNEL); + if (!evt) + return -ENOMEM; + *evt = (struct gzvm_ioevent) { + .addr = args->addr, + .len = args->len, + .evt_ctx = evt_ctx, + }; + if (args->flags & GZVM_IOEVENTFD_FLAG_DATAMATCH) { + evt->datamatch = args->datamatch; + evt->wildcard = false; + } else { + evt->wildcard = true; + } + + if (ioeventfd_check_collision(gzvm, evt)) { + ret = -EEXIST; + goto err_free; + } + + mutex_lock(&gzvm->lock); + list_add_tail(&evt->list, &gzvm->ioevents); + mutex_unlock(&gzvm->lock); + + return 0; + +err_free: + kfree(evt); + eventfd_ctx_put(evt_ctx); + return ret; +} + +/** + * gzvm_ioeventfd_check_valid() - Check user arguments is valid. + * @args: Pointer to gzvm_ioeventfd. + * + * Return: + * * true if user arguments are valid. + * * false if user arguments are invalid. + */ +static bool gzvm_ioeventfd_check_valid(struct gzvm_ioeventfd *args) +{ + /* must be natural-word sized, or 0 to ignore length */ + switch (args->len) { + case 0: + case 1: + case 2: + case 4: + case 8: + break; + default: + return false; + } + + /* check for range overflow */ + if (args->addr + args->len < args->addr) + return false; + + /* check for extra flags that we don't understand */ + if (args->flags & ~GZVM_IOEVENTFD_VALID_FLAG_MASK) + return false; + + /* ioeventfd with no length can't be combined with DATAMATCH */ + if (!args->len && (args->flags & GZVM_IOEVENTFD_FLAG_DATAMATCH)) + return false; + + /* gzvm does not support pio bus ioeventfd */ + if (args->flags & GZVM_IOEVENTFD_FLAG_PIO) + return false; + + return true; +} + +/** + * gzvm_ioeventfd() - Register ioevent to ioevent list. + * @gzvm: Pointer to gzvm. + * @args: Pointer to gzvm_ioeventfd. + * + * Return: + * * 0 - Success. + * * Negative - Failure. + */ +int gzvm_ioeventfd(struct gzvm *gzvm, struct gzvm_ioeventfd *args) +{ + if (gzvm_ioeventfd_check_valid(args) == false) + return -EINVAL; + + if (args->flags & GZVM_IOEVENTFD_FLAG_DEASSIGN) + return gzvm_deassign_ioeventfd(gzvm, args); + return gzvm_assign_ioeventfd(gzvm, args); +} + +/** + * gzvm_ioevent_write() - Travers this vm's registered ioeventfd to see if + * need notifying it. + * @vcpu: Pointer to vcpu. + * @addr: mmio address. + * @len: mmio size. + * @val: Pointer to void. + * + * Return: + * * true if this io is already sent to ioeventfd's listener. + * * false if we cannot find any ioeventfd registering this mmio write. + */ +bool gzvm_ioevent_write(struct gzvm_vcpu *vcpu, __u64 addr, int len, + const void *val) +{ + struct gzvm_ioevent *e; + + list_for_each_entry(e, &vcpu->gzvm->ioevents, list) { + if (gzvm_ioevent_in_range(e, addr, len, val)) { + eventfd_signal(e->evt_ctx); + return true; + } + } + return false; +} + +int gzvm_init_ioeventfd(struct gzvm *gzvm) +{ + INIT_LIST_HEAD(&gzvm->ioevents); + + return 0; +} diff --git a/drivers/virt/geniezone/gzvm_vcpu.c b/drivers/virt/geniezone/gzvm_vcpu.c index 598f0ed2dbb5..77138e749e9a 100644 --- a/drivers/virt/geniezone/gzvm_vcpu.c +++ b/drivers/virt/geniezone/gzvm_vcpu.c @@ -51,6 +51,30 @@ static long gzvm_vcpu_update_one_reg(struct gzvm_vcpu *vcpu, return 0; } +/** + * gzvm_vcpu_handle_mmio() - Handle mmio in kernel space. + * @vcpu: Pointer to vcpu. + * + * Return: + * * true - This mmio exit has been processed. + * * false - This mmio exit has not been processed, require userspace. + */ +static bool gzvm_vcpu_handle_mmio(struct gzvm_vcpu *vcpu) +{ + __u64 addr; + __u32 len; + const void *val_ptr; + + /* So far, we don't have in-kernel mmio read handler */ + if (!vcpu->run->mmio.is_write) + return false; + addr = vcpu->run->mmio.phys_addr; + len = vcpu->run->mmio.size; + val_ptr = &vcpu->run->mmio.data; + + return gzvm_ioevent_write(vcpu, addr, len, val_ptr); +} + /** * gzvm_vcpu_run() - Handle vcpu run ioctl, entry point to guest and exit * point from guest @@ -82,7 +106,8 @@ static long gzvm_vcpu_run(struct gzvm_vcpu *vcpu, void __user *argp) switch (exit_reason) { case GZVM_EXIT_MMIO: - need_userspace = true; + if (!gzvm_vcpu_handle_mmio(vcpu)) + need_userspace = true; break; /** * it's geniezone's responsibility to fill corresponding data diff --git a/drivers/virt/geniezone/gzvm_vm.c b/drivers/virt/geniezone/gzvm_vm.c index 2ab4391ff16a..d67bf647b615 100644 --- a/drivers/virt/geniezone/gzvm_vm.c +++ b/drivers/virt/geniezone/gzvm_vm.c @@ -223,6 +223,16 @@ static long gzvm_vm_ioctl(struct file *filp, unsigned int ioctl, ret = gzvm_irqfd(gzvm, &data); break; } + case GZVM_IOEVENTFD: { + struct gzvm_ioeventfd data; + + if (copy_from_user(&data, argp, sizeof(data))) { + ret = -EFAULT; + goto out; + } + ret = gzvm_ioeventfd(gzvm, &data); + break; + } case GZVM_ENABLE_CAP: { struct gzvm_enable_cap cap; @@ -299,6 +309,13 @@ static struct gzvm *gzvm_create_vm(unsigned long vm_type) return ERR_PTR(ret); } + ret = gzvm_init_ioeventfd(gzvm); + if (ret) { + pr_err("Failed to initialize ioeventfd\n"); + kfree(gzvm); + return ERR_PTR(ret); + } + mutex_lock(&gzvm_list_lock); list_add(&gzvm->vm_list, &gzvm_list); mutex_unlock(&gzvm_list_lock); diff --git a/include/linux/gzvm_drv.h b/include/linux/gzvm_drv.h index 676e6b5714e8..406bc9f821b2 100644 --- a/include/linux/gzvm_drv.h +++ b/include/linux/gzvm_drv.h @@ -6,6 +6,7 @@ #ifndef __GZVM_DRV_H__ #define __GZVM_DRV_H__ +#include #include #include #include @@ -95,6 +96,8 @@ struct gzvm { struct mutex resampler_lock; } irqfds; + struct list_head ioevents; + struct list_head vm_list; u16 vm_id; @@ -149,4 +152,13 @@ void gzvm_drv_irqfd_exit(void); int gzvm_vm_irqfd_init(struct gzvm *gzvm); void gzvm_vm_irqfd_release(struct gzvm *gzvm); +int gzvm_init_ioeventfd(struct gzvm *gzvm); +int gzvm_ioeventfd(struct gzvm *gzvm, struct gzvm_ioeventfd *args); +bool gzvm_ioevent_write(struct gzvm_vcpu *vcpu, __u64 addr, int len, + const void *val); +void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt); +struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr); +void add_wait_queue_priority(struct wait_queue_head *wq_head, + struct wait_queue_entry *wq_entry); + #endif /* __GZVM_DRV_H__ */ diff --git a/include/uapi/linux/gzvm.h b/include/uapi/linux/gzvm.h index cb02f278972f..ef433e311fa7 100644 --- a/include/uapi/linux/gzvm.h +++ b/include/uapi/linux/gzvm.h @@ -335,4 +335,29 @@ struct gzvm_irqfd { #define GZVM_IRQFD _IOW(GZVM_IOC_MAGIC, 0x76, struct gzvm_irqfd) +enum { + gzvm_ioeventfd_flag_nr_datamatch = 0, + gzvm_ioeventfd_flag_nr_pio = 1, + gzvm_ioeventfd_flag_nr_deassign = 2, + gzvm_ioeventfd_flag_nr_max, +}; + +#define GZVM_IOEVENTFD_FLAG_DATAMATCH (1 << gzvm_ioeventfd_flag_nr_datamatch) +#define GZVM_IOEVENTFD_FLAG_PIO (1 << gzvm_ioeventfd_flag_nr_pio) +#define GZVM_IOEVENTFD_FLAG_DEASSIGN (1 << gzvm_ioeventfd_flag_nr_deassign) +#define GZVM_IOEVENTFD_VALID_FLAG_MASK ((1 << gzvm_ioeventfd_flag_nr_max) - 1) + +struct gzvm_ioeventfd { + __u64 datamatch; + /* private: legal pio/mmio address */ + __u64 addr; + /* private: 1, 2, 4, or 8 bytes; or 0 to ignore length */ + __u32 len; + __s32 fd; + __u32 flags; + __u8 pad[36]; +}; + +#define GZVM_IOEVENTFD _IOW(GZVM_IOC_MAGIC, 0x79, struct gzvm_ioeventfd) + #endif /* __GZVM_H__ */