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commit 460023a5d1d2aa0f733b6708b2fae5ea9f9dfec0
parent a5f2bd479f58f171a16a9a4f3b4e748ab3057c0f
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 26 Dec 2018 11:35:07 -0800

Merge tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "Xen features and fixes:

   - a series to enable KVM guests to be booted by qemu via the Xen PVH
     boot entry for speeding up KVM guest tests

   - a series for a common driver to be used by Xen PV frontends (right
     now drm and sound)

   - two other fixes in Xen related code"

* tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  ALSA: xen-front: Use Xen common shared buffer implementation
  drm/xen-front: Use Xen common shared buffer implementation
  xen: Introduce shared buffer helpers for page directory...
  xen/pciback: Check dev_data before using it
  kprobes/x86/xen: blacklist non-attachable xen interrupt functions
  KVM: x86: Allow Qemu/KVM to use PVH entry point
  xen/pvh: Add memory map pointer to hvm_start_info struct
  xen/pvh: Move Xen code for getting mem map via hcall out of common file
  xen/pvh: Move Xen specific PVH VM initialization out of common file
  xen/pvh: Create a new file for Xen specific PVH code
  xen/pvh: Move PVH entry code out of Xen specific tree
  xen/pvh: Split CONFIG_XEN_PVH into CONFIG_PVH and CONFIG_XEN_PVH

Diffstat:
MMAINTAINERS | 1+
March/x86/Kbuild | 2++
March/x86/Kconfig | 6++++++
March/x86/kernel/head_64.S | 2+-
Aarch/x86/platform/pvh/Makefile | 5+++++
Aarch/x86/platform/pvh/enlighten.c | 137+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Rarch/x86/xen/xen-pvh.S -> arch/x86/platform/pvh/head.S | 0
March/x86/xen/Kconfig | 3++-
March/x86/xen/Makefile | 2--
March/x86/xen/enlighten_pvh.c | 92+++++++++++++++----------------------------------------------------------------
March/x86/xen/xen-asm_64.S | 2++
Mdrivers/gpu/drm/xen/Kconfig | 1+
Mdrivers/gpu/drm/xen/Makefile | 1-
Mdrivers/gpu/drm/xen/xen_drm_front.c | 65+++++++++++++++++++++++++----------------------------------------
Mdrivers/gpu/drm/xen/xen_drm_front_gem.c | 1-
Ddrivers/gpu/drm/xen/xen_drm_front_shbuf.c | 414-------------------------------------------------------------------------------
Ddrivers/gpu/drm/xen/xen_drm_front_shbuf.h | 64----------------------------------------------------------------
Mdrivers/xen/Kconfig | 3+++
Mdrivers/xen/Makefile | 1+
Adrivers/xen/xen-front-pgdir-shbuf.c | 553+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Mdrivers/xen/xen-pciback/pci_stub.c | 3++-
Minclude/xen/interface/hvm/start_info.h | 63++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
Ainclude/xen/xen-front-pgdir-shbuf.h | 89+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Minclude/xen/xen.h | 3+++
Msound/xen/Kconfig | 1+
Msound/xen/Makefile | 1-
Msound/xen/xen_snd_front.c | 7++++---
Msound/xen/xen_snd_front.h | 4++--
Msound/xen/xen_snd_front_alsa.c | 102+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------------
Dsound/xen/xen_snd_front_shbuf.c | 194-------------------------------------------------------------------------------
Dsound/xen/xen_snd_front_shbuf.h | 36------------------------------------
31 files changed, 996 insertions(+), 862 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS @@ -16590,6 +16590,7 @@ L: xen-devel@lists.xenproject.org (moderated for non-subscribers) T: git git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git S: Supported F: arch/x86/xen/ +F: arch/x86/platform/pvh/ F: drivers/*/xen-*front.c F: drivers/xen/ F: arch/x86/include/asm/xen/ diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild @@ -7,6 +7,8 @@ obj-$(CONFIG_KVM) += kvm/ # Xen paravirtualization support obj-$(CONFIG_XEN) += xen/ +obj-$(CONFIG_PVH) += platform/pvh/ + # Hyper-V paravirtualization support obj-$(subst m,y,$(CONFIG_HYPERV)) += hyperv/ diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig @@ -796,6 +796,12 @@ config KVM_GUEST underlying device model, the host provides the guest with timing infrastructure such as time of day, and system time +config PVH + bool "Support for running PVH guests" + ---help--- + This option enables the PVH entry point for guest virtual machines + as specified in the x86/HVM direct boot ABI. + config KVM_DEBUG_FS bool "Enable debug information for KVM Guests in debugfs" depends on KVM_GUEST && DEBUG_FS diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S @@ -386,7 +386,7 @@ NEXT_PAGE(early_dynamic_pgts) .data -#if defined(CONFIG_XEN_PV) || defined(CONFIG_XEN_PVH) +#if defined(CONFIG_XEN_PV) || defined(CONFIG_PVH) NEXT_PGD_PAGE(init_top_pgt) .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC .org init_top_pgt + L4_PAGE_OFFSET*8, 0 diff --git a/arch/x86/platform/pvh/Makefile b/arch/x86/platform/pvh/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +OBJECT_FILES_NON_STANDARD_head.o := y + +obj-$(CONFIG_PVH) += enlighten.o +obj-$(CONFIG_PVH) += head.o diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/acpi.h> + +#include <xen/hvc-console.h> + +#include <asm/io_apic.h> +#include <asm/hypervisor.h> +#include <asm/e820/api.h> +#include <asm/x86_init.h> + +#include <asm/xen/interface.h> + +#include <xen/xen.h> +#include <xen/interface/hvm/start_info.h> + +/* + * PVH variables. + * + * pvh_bootparams and pvh_start_info need to live in the data segment since + * they are used after startup_{32|64}, which clear .bss, are invoked. + */ +struct boot_params pvh_bootparams __attribute__((section(".data"))); +struct hvm_start_info pvh_start_info __attribute__((section(".data"))); + +unsigned int pvh_start_info_sz = sizeof(pvh_start_info); + +static u64 pvh_get_root_pointer(void) +{ + return pvh_start_info.rsdp_paddr; +} + +/* + * Xen guests are able to obtain the memory map from the hypervisor via the + * HYPERVISOR_memory_op hypercall. + * If we are trying to boot a Xen PVH guest, it is expected that the kernel + * will have been configured to provide an override for this routine to do + * just that. + */ +void __init __weak mem_map_via_hcall(struct boot_params *ptr __maybe_unused) +{ + xen_raw_printk("Error: Could not find memory map\n"); + BUG(); +} + +static void __init init_pvh_bootparams(bool xen_guest) +{ + memset(&pvh_bootparams, 0, sizeof(pvh_bootparams)); + + if ((pvh_start_info.version > 0) && (pvh_start_info.memmap_entries)) { + struct hvm_memmap_table_entry *ep; + int i; + + ep = __va(pvh_start_info.memmap_paddr); + pvh_bootparams.e820_entries = pvh_start_info.memmap_entries; + + for (i = 0; i < pvh_bootparams.e820_entries ; i++, ep++) { + pvh_bootparams.e820_table[i].addr = ep->addr; + pvh_bootparams.e820_table[i].size = ep->size; + pvh_bootparams.e820_table[i].type = ep->type; + } + } else if (xen_guest) { + mem_map_via_hcall(&pvh_bootparams); + } else { + /* Non-xen guests are not supported by version 0 */ + BUG(); + } + + if (pvh_bootparams.e820_entries < E820_MAX_ENTRIES_ZEROPAGE - 1) { + pvh_bootparams.e820_table[pvh_bootparams.e820_entries].addr = + ISA_START_ADDRESS; + pvh_bootparams.e820_table[pvh_bootparams.e820_entries].size = + ISA_END_ADDRESS - ISA_START_ADDRESS; + pvh_bootparams.e820_table[pvh_bootparams.e820_entries].type = + E820_TYPE_RESERVED; + pvh_bootparams.e820_entries++; + } else + xen_raw_printk("Warning: Can fit ISA range into e820\n"); + + pvh_bootparams.hdr.cmd_line_ptr = + pvh_start_info.cmdline_paddr; + + /* The first module is always ramdisk. */ + if (pvh_start_info.nr_modules) { + struct hvm_modlist_entry *modaddr = + __va(pvh_start_info.modlist_paddr); + pvh_bootparams.hdr.ramdisk_image = modaddr->paddr; + pvh_bootparams.hdr.ramdisk_size = modaddr->size; + } + + /* + * See Documentation/x86/boot.txt. + * + * Version 2.12 supports Xen entry point but we will use default x86/PC + * environment (i.e. hardware_subarch 0). + */ + pvh_bootparams.hdr.version = (2 << 8) | 12; + pvh_bootparams.hdr.type_of_loader = ((xen_guest ? 0x9 : 0xb) << 4) | 0; + + x86_init.acpi.get_root_pointer = pvh_get_root_pointer; +} + +/* + * If we are trying to boot a Xen PVH guest, it is expected that the kernel + * will have been configured to provide the required override for this routine. + */ +void __init __weak xen_pvh_init(void) +{ + xen_raw_printk("Error: Missing xen PVH initialization\n"); + BUG(); +} + +static void hypervisor_specific_init(bool xen_guest) +{ + if (xen_guest) + xen_pvh_init(); +} + +/* + * This routine (and those that it might call) should not use + * anything that lives in .bss since that segment will be cleared later. + */ +void __init xen_prepare_pvh(void) +{ + + u32 msr = xen_cpuid_base(); + bool xen_guest = !!msr; + + if (pvh_start_info.magic != XEN_HVM_START_MAGIC_VALUE) { + xen_raw_printk("Error: Unexpected magic value (0x%08x)\n", + pvh_start_info.magic); + BUG(); + } + + hypervisor_specific_init(xen_guest); + + init_pvh_bootparams(xen_guest); +} diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/platform/pvh/head.S diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig @@ -74,6 +74,7 @@ config XEN_DEBUG_FS Enabling this option may incur a significant performance overhead. config XEN_PVH - bool "Support for running as a PVH guest" + bool "Support for running as a Xen PVH guest" depends on XEN && XEN_PVHVM && ACPI + select PVH def_bool n diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile @@ -1,6 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 OBJECT_FILES_NON_STANDARD_xen-asm_$(BITS).o := y -OBJECT_FILES_NON_STANDARD_xen-pvh.o := y ifdef CONFIG_FUNCTION_TRACER # Do not profile debug and lowlevel utilities @@ -38,7 +37,6 @@ obj-$(CONFIG_XEN_PV) += xen-asm.o obj-$(CONFIG_XEN_PV) += xen-asm_$(BITS).o obj-$(CONFIG_XEN_PVH) += enlighten_pvh.o -obj-$(CONFIG_XEN_PVH) += xen-pvh.o obj-$(CONFIG_EVENT_TRACING) += trace.o diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c @@ -6,103 +6,45 @@ #include <asm/io_apic.h> #include <asm/hypervisor.h> #include <asm/e820/api.h> -#include <asm/x86_init.h> +#include <xen/xen.h> #include <asm/xen/interface.h> #include <asm/xen/hypercall.h> -#include <xen/xen.h> #include <xen/interface/memory.h> -#include <xen/interface/hvm/start_info.h> /* * PVH variables. * - * xen_pvh pvh_bootparams and pvh_start_info need to live in data segment - * since they are used after startup_{32|64}, which clear .bss, are invoked. + * The variable xen_pvh needs to live in the data segment since it is used + * after startup_{32|64} is invoked, which will clear the .bss segment. */ bool xen_pvh __attribute__((section(".data"))) = 0; -struct boot_params pvh_bootparams __attribute__((section(".data"))); -struct hvm_start_info pvh_start_info __attribute__((section(".data"))); - -unsigned int pvh_start_info_sz = sizeof(pvh_start_info); -static u64 pvh_get_root_pointer(void) +void __init xen_pvh_init(void) { - return pvh_start_info.rsdp_paddr; + u32 msr; + u64 pfn; + + xen_pvh = 1; + xen_start_flags = pvh_start_info.flags; + + msr = cpuid_ebx(xen_cpuid_base() + 2); + pfn = __pa(hypercall_page); + wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32)); } -static void __init init_pvh_bootparams(void) +void __init mem_map_via_hcall(struct boot_params *boot_params_p) { struct xen_memory_map memmap; int rc; - memset(&pvh_bootparams, 0, sizeof(pvh_bootparams)); - - memmap.nr_entries = ARRAY_SIZE(pvh_bootparams.e820_table); - set_xen_guest_handle(memmap.buffer, pvh_bootparams.e820_table); + memmap.nr_entries = ARRAY_SIZE(boot_params_p->e820_table); + set_xen_guest_handle(memmap.buffer, boot_params_p->e820_table); rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap); if (rc) { xen_raw_printk("XENMEM_memory_map failed (%d)\n", rc); BUG(); } - pvh_bootparams.e820_entries = memmap.nr_entries; - - if (pvh_bootparams.e820_entries < E820_MAX_ENTRIES_ZEROPAGE - 1) { - pvh_bootparams.e820_table[pvh_bootparams.e820_entries].addr = - ISA_START_ADDRESS; - pvh_bootparams.e820_table[pvh_bootparams.e820_entries].size = - ISA_END_ADDRESS - ISA_START_ADDRESS; - pvh_bootparams.e820_table[pvh_bootparams.e820_entries].type = - E820_TYPE_RESERVED; - pvh_bootparams.e820_entries++; - } else - xen_raw_printk("Warning: Can fit ISA range into e820\n"); - - pvh_bootparams.hdr.cmd_line_ptr = - pvh_start_info.cmdline_paddr; - - /* The first module is always ramdisk. */ - if (pvh_start_info.nr_modules) { - struct hvm_modlist_entry *modaddr = - __va(pvh_start_info.modlist_paddr); - pvh_bootparams.hdr.ramdisk_image = modaddr->paddr; - pvh_bootparams.hdr.ramdisk_size = modaddr->size; - } - - /* - * See Documentation/x86/boot.txt. - * - * Version 2.12 supports Xen entry point but we will use default x86/PC - * environment (i.e. hardware_subarch 0). - */ - pvh_bootparams.hdr.version = (2 << 8) | 12; - pvh_bootparams.hdr.type_of_loader = (9 << 4) | 0; /* Xen loader */ - - x86_init.acpi.get_root_pointer = pvh_get_root_pointer; -} - -/* - * This routine (and those that it might call) should not use - * anything that lives in .bss since that segment will be cleared later. - */ -void __init xen_prepare_pvh(void) -{ - u32 msr; - u64 pfn; - - if (pvh_start_info.magic != XEN_HVM_START_MAGIC_VALUE) { - xen_raw_printk("Error: Unexpected magic value (0x%08x)\n", - pvh_start_info.magic); - BUG(); - } - - xen_pvh = 1; - xen_start_flags = pvh_start_info.flags; - - msr = cpuid_ebx(xen_cpuid_base() + 2); - pfn = __pa(hypercall_page); - wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32)); - - init_pvh_bootparams(); + boot_params_p->e820_entries = memmap.nr_entries; } diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S @@ -12,6 +12,7 @@ #include <asm/segment.h> #include <asm/asm-offsets.h> #include <asm/thread_info.h> +#include <asm/asm.h> #include <xen/interface/xen.h> @@ -24,6 +25,7 @@ ENTRY(xen_\name) pop %r11 jmp \name END(xen_\name) +_ASM_NOKPROBE(xen_\name) .endm xen_pv_trap divide_error diff --git a/drivers/gpu/drm/xen/Kconfig b/drivers/gpu/drm/xen/Kconfig @@ -12,6 +12,7 @@ config DRM_XEN_FRONTEND select DRM_KMS_HELPER select VIDEOMODE_HELPERS select XEN_XENBUS_FRONTEND + select XEN_FRONT_PGDIR_SHBUF help Choose this option if you want to enable a para-virtualized frontend DRM/KMS driver for Xen guest OSes. diff --git a/drivers/gpu/drm/xen/Makefile b/drivers/gpu/drm/xen/Makefile @@ -4,7 +4,6 @@ drm_xen_front-objs := xen_drm_front.o \ xen_drm_front_kms.o \ xen_drm_front_conn.o \ xen_drm_front_evtchnl.o \ - xen_drm_front_shbuf.o \ xen_drm_front_cfg.o \ xen_drm_front_gem.o diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c @@ -19,6 +19,7 @@ #include <xen/xen.h> #include <xen/xenbus.h> +#include <xen/xen-front-pgdir-shbuf.h> #include <xen/interface/io/displif.h> #include "xen_drm_front.h" @@ -26,28 +27,20 @@ #include "xen_drm_front_evtchnl.h" #include "xen_drm_front_gem.h" #include "xen_drm_front_kms.h" -#include "xen_drm_front_shbuf.h" struct xen_drm_front_dbuf { struct list_head list; u64 dbuf_cookie; u64 fb_cookie; - struct xen_drm_front_shbuf *shbuf; + + struct xen_front_pgdir_shbuf shbuf; }; -static int dbuf_add_to_list(struct xen_drm_front_info *front_info, - struct xen_drm_front_shbuf *shbuf, u64 dbuf_cookie) +static void dbuf_add_to_list(struct xen_drm_front_info *front_info, + struct xen_drm_front_dbuf *dbuf, u64 dbuf_cookie) { - struct xen_drm_front_dbuf *dbuf; - - dbuf = kzalloc(sizeof(*dbuf), GFP_KERNEL); - if (!dbuf) - return -ENOMEM; - dbuf->dbuf_cookie = dbuf_cookie; - dbuf->shbuf = shbuf; list_add(&dbuf->list, &front_info->dbuf_list); - return 0; } static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list, @@ -62,15 +55,6 @@ static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list, return NULL; } -static void dbuf_flush_fb(struct list_head *dbuf_list, u64 fb_cookie) -{ - struct xen_drm_front_dbuf *buf, *q; - - list_for_each_entry_safe(buf, q, dbuf_list, list) - if (buf->fb_cookie == fb_cookie) - xen_drm_front_shbuf_flush(buf->shbuf); -} - static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie) { struct xen_drm_front_dbuf *buf, *q; @@ -78,8 +62,8 @@ static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie) list_for_each_entry_safe(buf, q, dbuf_list, list) if (buf->dbuf_cookie == dbuf_cookie) { list_del(&buf->list); - xen_drm_front_shbuf_unmap(buf->shbuf); - xen_drm_front_shbuf_free(buf->shbuf); + xen_front_pgdir_shbuf_unmap(&buf->shbuf); + xen_front_pgdir_shbuf_free(&buf->shbuf); kfree(buf); break; } @@ -91,8 +75,8 @@ static void dbuf_free_all(struct list_head *dbuf_list) list_for_each_entry_safe(buf, q, dbuf_list, list) { list_del(&buf->list); - xen_drm_front_shbuf_unmap(buf->shbuf); - xen_drm_front_shbuf_free(buf->shbuf); + xen_front_pgdir_shbuf_unmap(&buf->shbuf); + xen_front_pgdir_shbuf_free(&buf->shbuf); kfree(buf); } } @@ -171,9 +155,9 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info, u32 bpp, u64 size, struct page **pages) { struct xen_drm_front_evtchnl *evtchnl; - struct xen_drm_front_shbuf *shbuf; + struct xen_drm_front_dbuf *dbuf; struct xendispl_req *req; - struct xen_drm_front_shbuf_cfg buf_cfg; + struct xen_front_pgdir_shbuf_cfg buf_cfg; unsigned long flags; int ret; @@ -181,28 +165,29 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info, if (unlikely(!evtchnl)) return -EIO; + dbuf = kzalloc(sizeof(*dbuf), GFP_KERNEL); + if (!dbuf) + return -ENOMEM; + + dbuf_add_to_list(front_info, dbuf, dbuf_cookie); + memset(&buf_cfg, 0, sizeof(buf_cfg)); buf_cfg.xb_dev = front_info->xb_dev; + buf_cfg.num_pages = DIV_ROUND_UP(size, PAGE_SIZE); buf_cfg.pages = pages; - buf_cfg.size = size; + buf_cfg.pgdir = &dbuf->shbuf; buf_cfg.be_alloc = front_info->cfg.be_alloc; - shbuf = xen_drm_front_shbuf_alloc(&buf_cfg); - if (IS_ERR(shbuf)) - return PTR_ERR(shbuf); - - ret = dbuf_add_to_list(front_info, shbuf, dbuf_cookie); - if (ret < 0) { - xen_drm_front_shbuf_free(shbuf); - return ret; - } + ret = xen_front_pgdir_shbuf_alloc(&buf_cfg); + if (ret < 0) + goto fail_shbuf_alloc; mutex_lock(&evtchnl->u.req.req_io_lock); spin_lock_irqsave(&front_info->io_lock, flags); req = be_prepare_req(evtchnl, XENDISPL_OP_DBUF_CREATE); req->op.dbuf_create.gref_directory = - xen_drm_front_shbuf_get_dir_start(shbuf); + xen_front_pgdir_shbuf_get_dir_start(&dbuf->shbuf); req->op.dbuf_create.buffer_sz = size; req->op.dbuf_create.dbuf_cookie = dbuf_cookie; req->op.dbuf_create.width = width; @@ -221,7 +206,7 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info, if (ret < 0) goto fail; - ret = xen_drm_front_shbuf_map(shbuf); + ret = xen_front_pgdir_shbuf_map(&dbuf->shbuf); if (ret < 0) goto fail; @@ -230,6 +215,7 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info, fail: mutex_unlock(&evtchnl->u.req.req_io_lock); +fail_shbuf_alloc: dbuf_free(&front_info->dbuf_list, dbuf_cookie); return ret; } @@ -358,7 +344,6 @@ int xen_drm_front_page_flip(struct xen_drm_front_info *front_info, if (unlikely(conn_idx >= front_info->num_evt_pairs)) return -EINVAL; - dbuf_flush_fb(&front_info->dbuf_list, fb_cookie); evtchnl = &front_info->evt_pairs[conn_idx].req; mutex_lock(&evtchnl->u.req.req_io_lock); diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -22,7 +22,6 @@ #include <xen/balloon.h> #include "xen_drm_front.h" -#include "xen_drm_front_shbuf.h" struct xen_gem_object { struct drm_gem_object base; diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.c b/drivers/gpu/drm/xen/xen_drm_front_shbuf.c @@ -1,414 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 OR MIT - -/* - * Xen para-virtual DRM device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> - */ - -#include <drm/drmP.h> - -#if defined(CONFIG_X86) -#include <drm/drm_cache.h> -#endif -#include <linux/errno.h> -#include <linux/mm.h> - -#include <asm/xen/hypervisor.h> -#include <xen/balloon.h> -#include <xen/xen.h> -#include <xen/xenbus.h> -#include <xen/interface/io/ring.h> -#include <xen/interface/io/displif.h> - -#include "xen_drm_front.h" -#include "xen_drm_front_shbuf.h" - -struct xen_drm_front_shbuf_ops { - /* - * Calculate number of grefs required to handle this buffer, - * e.g. if grefs are required for page directory only or the buffer - * pages as well. - */ - void (*calc_num_grefs)(struct xen_drm_front_shbuf *buf); - /* Fill page directory according to para-virtual display protocol. */ - void (*fill_page_dir)(struct xen_drm_front_shbuf *buf); - /* Claim grant references for the pages of the buffer. */ - int (*grant_refs_for_buffer)(struct xen_drm_front_shbuf *buf, - grant_ref_t *priv_gref_head, int gref_idx); - /* Map grant references of the buffer. */ - int (*map)(struct xen_drm_front_shbuf *buf); - /* Unmap grant references of the buffer. */ - int (*unmap)(struct xen_drm_front_shbuf *buf); -}; - -grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf) -{ - if (!buf->grefs) - return GRANT_INVALID_REF; - - return buf->grefs[0]; -} - -int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf) -{ - if (buf->ops->map) - return buf->ops->map(buf); - - /* no need to map own grant references */ - return 0; -} - -int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf) -{ - if (buf->ops->unmap) - return buf->ops->unmap(buf); - - /* no need to unmap own grant references */ - return 0; -} - -void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf) -{ -#if defined(CONFIG_X86) - drm_clflush_pages(buf->pages, buf->num_pages); -#endif -} - -void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf) -{ - if (buf->grefs) { - int i; - - for (i = 0; i < buf->num_grefs; i++) - if (buf->grefs[i] != GRANT_INVALID_REF) - gnttab_end_foreign_access(buf->grefs[i], - 0, 0UL); - } - kfree(buf->grefs); - kfree(buf->directory); - kfree(buf); -} - -/* - * number of grefs a page can hold with respect to the - * struct xendispl_page_directory header - */ -#define XEN_DRM_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \ - offsetof(struct xendispl_page_directory, gref)) / \ - sizeof(grant_ref_t)) - -static int get_num_pages_dir(struct xen_drm_front_shbuf *buf) -{ - /* number of pages the page directory consumes itself */ - return DIV_ROUND_UP(buf->num_pages, XEN_DRM_NUM_GREFS_PER_PAGE); -} - -static void backend_calc_num_grefs(struct xen_drm_front_shbuf *buf) -{ - /* only for pages the page directory consumes itself */ - buf->num_grefs = get_num_pages_dir(buf); -} - -static void guest_calc_num_grefs(struct xen_drm_front_shbuf *buf) -{ - /* - * number of pages the page directory consumes itself - * plus grefs for the buffer pages - */ - buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages; -} - -#define xen_page_to_vaddr(page) \ - ((uintptr_t)pfn_to_kaddr(page_to_xen_pfn(page))) - -static int backend_unmap(struct xen_drm_front_shbuf *buf) -{ - struct gnttab_unmap_grant_ref *unmap_ops; - int i, ret; - - if (!buf->pages || !buf->backend_map_handles || !buf->grefs) - return 0; - - unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops), - GFP_KERNEL); - if (!unmap_ops) { - DRM_ERROR("Failed to get memory while unmapping\n"); - return -ENOMEM; - } - - for (i = 0; i < buf->num_pages; i++) { - phys_addr_t addr; - - addr = xen_page_to_vaddr(buf->pages[i]); - gnttab_set_unmap_op(&unmap_ops[i], addr, GNTMAP_host_map, - buf->backend_map_handles[i]); - } - - ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages, - buf->num_pages); - - for (i = 0; i < buf->num_pages; i++) { - if (unlikely(unmap_ops[i].status != GNTST_okay)) - DRM_ERROR("Failed to unmap page %d: %d\n", - i, unmap_ops[i].status); - } - - if (ret) - DRM_ERROR("Failed to unmap grant references, ret %d", ret); - - kfree(unmap_ops); - kfree(buf->backend_map_handles); - buf->backend_map_handles = NULL; - return ret; -} - -static int backend_map(struct xen_drm_front_shbuf *buf) -{ - struct gnttab_map_grant_ref *map_ops = NULL; - unsigned char *ptr; - int ret, cur_gref, cur_dir_page, cur_page, grefs_left; - - map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL); - if (!map_ops) - return -ENOMEM; - - buf->backend_map_handles = kcalloc(buf->num_pages, - sizeof(*buf->backend_map_handles), - GFP_KERNEL); - if (!buf->backend_map_handles) { - kfree(map_ops); - return -ENOMEM; - } - - /* - * read page directory to get grefs from the backend: for external - * buffer we only allocate buf->grefs for the page directory, - * so buf->num_grefs has number of pages in the page directory itself - */ - ptr = buf->directory; - grefs_left = buf->num_pages; - cur_page = 0; - for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) { - struct xendispl_page_directory *page_dir = - (struct xendispl_page_directory *)ptr; - int to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; - - if (to_copy > grefs_left) - to_copy = grefs_left; - - for (cur_gref = 0; cur_gref < to_copy; cur_gref++) { - phys_addr_t addr; - - addr = xen_page_to_vaddr(buf->pages[cur_page]); - gnttab_set_map_op(&map_ops[cur_page], addr, - GNTMAP_host_map, - page_dir->gref[cur_gref], - buf->xb_dev->otherend_id); - cur_page++; - } - - grefs_left -= to_copy; - ptr += PAGE_SIZE; - } - ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages); - - /* save handles even if error, so we can unmap */ - for (cur_page = 0; cur_page < buf->num_pages; cur_page++) { - buf->backend_map_handles[cur_page] = map_ops[cur_page].handle; - if (unlikely(map_ops[cur_page].status != GNTST_okay)) - DRM_ERROR("Failed to map page %d: %d\n", - cur_page, map_ops[cur_page].status); - } - - if (ret) { - DRM_ERROR("Failed to map grant references, ret %d", ret); - backend_unmap(buf); - } - - kfree(map_ops); - return ret; -} - -static void backend_fill_page_dir(struct xen_drm_front_shbuf *buf) -{ - struct xendispl_page_directory *page_dir; - unsigned char *ptr; - int i, num_pages_dir; - - ptr = buf->directory; - num_pages_dir = get_num_pages_dir(buf); - - /* fill only grefs for the page directory itself */ - for (i = 0; i < num_pages_dir - 1; i++) { - page_dir = (struct xendispl_page_directory *)ptr; - - page_dir->gref_dir_next_page = buf->grefs[i + 1]; - ptr += PAGE_SIZE; - } - /* last page must say there is no more pages */ - page_dir = (struct xendispl_page_directory *)ptr; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; -} - -static void guest_fill_page_dir(struct xen_drm_front_shbuf *buf) -{ - unsigned char *ptr; - int cur_gref, grefs_left, to_copy, i, num_pages_dir; - - ptr = buf->directory; - num_pages_dir = get_num_pages_dir(buf); - - /* - * while copying, skip grefs at start, they are for pages - * granted for the page directory itself - */ - cur_gref = num_pages_dir; - grefs_left = buf->num_pages; - for (i = 0; i < num_pages_dir; i++) { - struct xendispl_page_directory *page_dir = - (struct xendispl_page_directory *)ptr; - - if (grefs_left <= XEN_DRM_NUM_GREFS_PER_PAGE) { - to_copy = grefs_left; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; - } else { - to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; - page_dir->gref_dir_next_page = buf->grefs[i + 1]; - } - memcpy(&page_dir->gref, &buf->grefs[cur_gref], - to_copy * sizeof(grant_ref_t)); - ptr += PAGE_SIZE; - grefs_left -= to_copy; - cur_gref += to_copy; - } -} - -static int guest_grant_refs_for_buffer(struct xen_drm_front_shbuf *buf, - grant_ref_t *priv_gref_head, - int gref_idx) -{ - int i, cur_ref, otherend_id; - - otherend_id = buf->xb_dev->otherend_id; - for (i = 0; i < buf->num_pages; i++) { - cur_ref = gnttab_claim_grant_reference(priv_gref_head); - if (cur_ref < 0) - return cur_ref; - - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, - xen_page_to_gfn(buf->pages[i]), - 0); - buf->grefs[gref_idx++] = cur_ref; - } - return 0; -} - -static int grant_references(struct xen_drm_front_shbuf *buf) -{ - grant_ref_t priv_gref_head; - int ret, i, j, cur_ref; - int otherend_id, num_pages_dir; - - ret = gnttab_alloc_grant_references(buf->num_grefs, &priv_gref_head); - if (ret < 0) { - DRM_ERROR("Cannot allocate grant references\n"); - return ret; - } - - otherend_id = buf->xb_dev->otherend_id; - j = 0; - num_pages_dir = get_num_pages_dir(buf); - for (i = 0; i < num_pages_dir; i++) { - unsigned long frame; - - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) - return cur_ref; - - frame = xen_page_to_gfn(virt_to_page(buf->directory + - PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - if (buf->ops->grant_refs_for_buffer) { - ret = buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j); - if (ret) - return ret; - } - - gnttab_free_grant_references(priv_gref_head); - return 0; -} - -static int alloc_storage(struct xen_drm_front_shbuf *buf) -{ - buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL); - if (!buf->grefs) - return -ENOMEM; - - buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL); - if (!buf->directory) - return -ENOMEM; - - return 0; -} - -/* - * For be allocated buffers we don't need grant_refs_for_buffer as those - * grant references are allocated at backend side - */ -static const struct xen_drm_front_shbuf_ops backend_ops = { - .calc_num_grefs = backend_calc_num_grefs, - .fill_page_dir = backend_fill_page_dir, - .map = backend_map, - .unmap = backend_unmap -}; - -/* For locally granted references we do not need to map/unmap the references */ -static const struct xen_drm_front_shbuf_ops local_ops = { - .calc_num_grefs = guest_calc_num_grefs, - .fill_page_dir = guest_fill_page_dir, - .grant_refs_for_buffer = guest_grant_refs_for_buffer, -}; - -struct xen_drm_front_shbuf * -xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg) -{ - struct xen_drm_front_shbuf *buf; - int ret; - - buf = kzalloc(sizeof(*buf), GFP_KERNEL); - if (!buf) - return ERR_PTR(-ENOMEM); - - if (cfg->be_alloc) - buf->ops = &backend_ops; - else - buf->ops = &local_ops; - - buf->xb_dev = cfg->xb_dev; - buf->num_pages = DIV_ROUND_UP(cfg->size, PAGE_SIZE); - buf->pages = cfg->pages; - - buf->ops->calc_num_grefs(buf); - - ret = alloc_storage(buf); - if (ret) - goto fail; - - ret = grant_references(buf); - if (ret) - goto fail; - - buf->ops->fill_page_dir(buf); - - return buf; - -fail: - xen_drm_front_shbuf_free(buf); - return ERR_PTR(ret); -} diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.h b/drivers/gpu/drm/xen/xen_drm_front_shbuf.h @@ -1,64 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 OR MIT */ - -/* - * Xen para-virtual DRM device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> - */ - -#ifndef __XEN_DRM_FRONT_SHBUF_H_ -#define __XEN_DRM_FRONT_SHBUF_H_ - -#include <linux/kernel.h> -#include <linux/scatterlist.h> - -#include <xen/grant_table.h> - -struct xen_drm_front_shbuf { - /* - * number of references granted for the backend use: - * - for allocated/imported dma-buf's this holds number of grant - * references for the page directory and pages of the buffer - * - for the buffer provided by the backend this holds number of - * grant references for the page directory as grant references for - * the buffer will be provided by the backend - */ - int num_grefs; - grant_ref_t *grefs; - unsigned char *directory; - - int num_pages; - struct page **pages; - - struct xenbus_device *xb_dev; - - /* these are the ops used internally depending on be_alloc mode */ - const struct xen_drm_front_shbuf_ops *ops; - - /* Xen map handles for the buffer allocated by the backend */ - grant_handle_t *backend_map_handles; -}; - -struct xen_drm_front_shbuf_cfg { - struct xenbus_device *xb_dev; - size_t size; - struct page **pages; - bool be_alloc; -}; - -struct xen_drm_front_shbuf * -xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg); - -grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf); - -int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf); - -int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf); - -void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf); - -void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf); - -#endif /* __XEN_DRM_FRONT_SHBUF_H_ */ diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig @@ -340,4 +340,7 @@ config XEN_SYMS config XEN_HAVE_VPMU bool +config XEN_FRONT_PGDIR_SHBUF + tristate + endmenu diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile @@ -44,3 +44,4 @@ xen-gntdev-y := gntdev.o xen-gntdev-$(CONFIG_XEN_GNTDEV_DMABUF) += gntdev-dmabuf.o xen-gntalloc-y := gntalloc.o xen-privcmd-y := privcmd.o privcmd-buf.o +obj-$(CONFIG_XEN_FRONT_PGDIR_SHBUF) += xen-front-pgdir-shbuf.o diff --git a/drivers/xen/xen-front-pgdir-shbuf.c b/drivers/xen/xen-front-pgdir-shbuf.c @@ -0,0 +1,553 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen frontend/backend page directory based shared buffer + * helper module. + * + * Copyright (C) 2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/mm.h> + +#include <asm/xen/hypervisor.h> +#include <xen/balloon.h> +#include <xen/xen.h> +#include <xen/xenbus.h> +#include <xen/interface/io/ring.h> + +#include <xen/xen-front-pgdir-shbuf.h> + +#ifndef GRANT_INVALID_REF +/* + * FIXME: usage of grant reference 0 as invalid grant reference: + * grant reference 0 is valid, but never exposed to a PV driver, + * because of the fact it is already in use/reserved by the PV console. + */ +#define GRANT_INVALID_REF 0 +#endif + +/** + * This structure represents the structure of a shared page + * that contains grant references to the pages of the shared + * buffer. This structure is common to many Xen para-virtualized + * protocols at include/xen/interface/io/ + */ +struct xen_page_directory { + grant_ref_t gref_dir_next_page; + grant_ref_t gref[1]; /* Variable length */ +}; + +/** + * Shared buffer ops which are differently implemented + * depending on the allocation mode, e.g. if the buffer + * is allocated by the corresponding backend or frontend. + * Some of the operations. + */ +struct xen_front_pgdir_shbuf_ops { + /* + * Calculate number of grefs required to handle this buffer, + * e.g. if grefs are required for page directory only or the buffer + * pages as well. + */ + void (*calc_num_grefs)(struct xen_front_pgdir_shbuf *buf); + + /* Fill page directory according to para-virtual display protocol. */ + void (*fill_page_dir)(struct xen_front_pgdir_shbuf *buf); + + /* Claim grant references for the pages of the buffer. */ + int (*grant_refs_for_buffer)(struct xen_front_pgdir_shbuf *buf, + grant_ref_t *priv_gref_head, int gref_idx); + + /* Map grant references of the buffer. */ + int (*map)(struct xen_front_pgdir_shbuf *buf); + + /* Unmap grant references of the buffer. */ + int (*unmap)(struct xen_front_pgdir_shbuf *buf); +}; + +/** + * Get granted reference to the very first page of the + * page directory. Usually this is passed to the backend, + * so it can find/fill the grant references to the buffer's + * pages. + * + * \param buf shared buffer which page directory is of interest. + * \return granted reference to the very first page of the + * page directory. + */ +grant_ref_t +xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf) +{ + if (!buf->grefs) + return GRANT_INVALID_REF; + + return buf->grefs[0]; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_get_dir_start); + +/** + * Map granted references of the shared buffer. + * + * Depending on the shared buffer mode of allocation + * (be_alloc flag) this can either do nothing (for buffers + * shared by the frontend itself) or map the provided granted + * references onto the backing storage (buf->pages). + * + * \param buf shared buffer which grants to be maped. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf) +{ + if (buf->ops && buf->ops->map) + return buf->ops->map(buf); + + /* No need to map own grant references. */ + return 0; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_map); + +/** + * Unmap granted references of the shared buffer. + * + * Depending on the shared buffer mode of allocation + * (be_alloc flag) this can either do nothing (for buffers + * shared by the frontend itself) or unmap the provided granted + * references. + * + * \param buf shared buffer which grants to be unmaped. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf) +{ + if (buf->ops && buf->ops->unmap) + return buf->ops->unmap(buf); + + /* No need to unmap own grant references. */ + return 0; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_unmap); + +/** + * Free all the resources of the shared buffer. + * + * \param buf shared buffer which resources to be freed. + */ +void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_shbuf *buf) +{ + if (buf->grefs) { + int i; + + for (i = 0; i < buf->num_grefs; i++) + if (buf->grefs[i] != GRANT_INVALID_REF) + gnttab_end_foreign_access(buf->grefs[i], + 0, 0UL); + } + kfree(buf->grefs); + kfree(buf->directory); +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_free); + +/* + * Number of grefs a page can hold with respect to the + * struct xen_page_directory header. + */ +#define XEN_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \ + offsetof(struct xen_page_directory, \ + gref)) / sizeof(grant_ref_t)) + +/** + * Get the number of pages the page directory consumes itself. + * + * \param buf shared buffer. + */ +static int get_num_pages_dir(struct xen_front_pgdir_shbuf *buf) +{ + return DIV_ROUND_UP(buf->num_pages, XEN_NUM_GREFS_PER_PAGE); +} + +/** + * Calculate the number of grant references needed to share the buffer + * and its pages when backend allocates the buffer. + * + * \param buf shared buffer. + */ +static void backend_calc_num_grefs(struct xen_front_pgdir_shbuf *buf) +{ + /* Only for pages the page directory consumes itself. */ + buf->num_grefs = get_num_pages_dir(buf); +} + +/** + * Calculate the number of grant references needed to share the buffer + * and its pages when frontend allocates the buffer. + * + * \param buf shared buffer. + */ +static void guest_calc_num_grefs(struct xen_front_pgdir_shbuf *buf) +{ + /* + * Number of pages the page directory consumes itself + * plus grefs for the buffer pages. + */ + buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages; +} + +#define xen_page_to_vaddr(page) \ + ((uintptr_t)pfn_to_kaddr(page_to_xen_pfn(page))) + +/** + * Unmap the buffer previously mapped with grant references + * provided by the backend. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int backend_unmap(struct xen_front_pgdir_shbuf *buf) +{ + struct gnttab_unmap_grant_ref *unmap_ops; + int i, ret; + + if (!buf->pages || !buf->backend_map_handles || !buf->grefs) + return 0; + + unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops), + GFP_KERNEL); + if (!unmap_ops) + return -ENOMEM; + + for (i = 0; i < buf->num_pages; i++) { + phys_addr_t addr; + + addr = xen_page_to_vaddr(buf->pages[i]); + gnttab_set_unmap_op(&unmap_ops[i], addr, GNTMAP_host_map, + buf->backend_map_handles[i]); + } + + ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages, + buf->num_pages); + + for (i = 0; i < buf->num_pages; i++) { + if (unlikely(unmap_ops[i].status != GNTST_okay)) + dev_err(&buf->xb_dev->dev, + "Failed to unmap page %d: %d\n", + i, unmap_ops[i].status); + } + + if (ret) + dev_err(&buf->xb_dev->dev, + "Failed to unmap grant references, ret %d", ret); + + kfree(unmap_ops); + kfree(buf->backend_map_handles); + buf->backend_map_handles = NULL; + return ret; +} + +/** + * Map the buffer with grant references provided by the backend. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int backend_map(struct xen_front_pgdir_shbuf *buf) +{ + struct gnttab_map_grant_ref *map_ops = NULL; + unsigned char *ptr; + int ret, cur_gref, cur_dir_page, cur_page, grefs_left; + + map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL); + if (!map_ops) + return -ENOMEM; + + buf->backend_map_handles = kcalloc(buf->num_pages, + sizeof(*buf->backend_map_handles), + GFP_KERNEL); + if (!buf->backend_map_handles) { + kfree(map_ops); + return -ENOMEM; + } + + /* + * Read page directory to get grefs from the backend: for external + * buffer we only allocate buf->grefs for the page directory, + * so buf->num_grefs has number of pages in the page directory itself. + */ + ptr = buf->directory; + grefs_left = buf->num_pages; + cur_page = 0; + for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) { + struct xen_page_directory *page_dir = + (struct xen_page_directory *)ptr; + int to_copy = XEN_NUM_GREFS_PER_PAGE; + + if (to_copy > grefs_left) + to_copy = grefs_left; + + for (cur_gref = 0; cur_gref < to_copy; cur_gref++) { + phys_addr_t addr; + + addr = xen_page_to_vaddr(buf->pages[cur_page]); + gnttab_set_map_op(&map_ops[cur_page], addr, + GNTMAP_host_map, + page_dir->gref[cur_gref], + buf->xb_dev->otherend_id); + cur_page++; + } + + grefs_left -= to_copy; + ptr += PAGE_SIZE; + } + ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages); + + /* Save handles even if error, so we can unmap. */ + for (cur_page = 0; cur_page < buf->num_pages; cur_page++) { + buf->backend_map_handles[cur_page] = map_ops[cur_page].handle; + if (unlikely(map_ops[cur_page].status != GNTST_okay)) + dev_err(&buf->xb_dev->dev, + "Failed to map page %d: %d\n", + cur_page, map_ops[cur_page].status); + } + + if (ret) { + dev_err(&buf->xb_dev->dev, + "Failed to map grant references, ret %d", ret); + backend_unmap(buf); + } + + kfree(map_ops); + return ret; +} + +/** + * Fill page directory with grant references to the pages of the + * page directory itself. + * + * The grant references to the buffer pages are provided by the + * backend in this case. + * + * \param buf shared buffer. + */ +static void backend_fill_page_dir(struct xen_front_pgdir_shbuf *buf) +{ + struct xen_page_directory *page_dir; + unsigned char *ptr; + int i, num_pages_dir; + + ptr = buf->directory; + num_pages_dir = get_num_pages_dir(buf); + + /* Fill only grefs for the page directory itself. */ + for (i = 0; i < num_pages_dir - 1; i++) { + page_dir = (struct xen_page_directory *)ptr; + + page_dir->gref_dir_next_page = buf->grefs[i + 1]; + ptr += PAGE_SIZE; + } + /* Last page must say there is no more pages. */ + page_dir = (struct xen_page_directory *)ptr; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; +} + +/** + * Fill page directory with grant references to the pages of the + * page directory and the buffer we share with the backend. + * + * \param buf shared buffer. + */ +static void guest_fill_page_dir(struct xen_front_pgdir_shbuf *buf) +{ + unsigned char *ptr; + int cur_gref, grefs_left, to_copy, i, num_pages_dir; + + ptr = buf->directory; + num_pages_dir = get_num_pages_dir(buf); + + /* + * While copying, skip grefs at start, they are for pages + * granted for the page directory itself. + */ + cur_gref = num_pages_dir; + grefs_left = buf->num_pages; + for (i = 0; i < num_pages_dir; i++) { + struct xen_page_directory *page_dir = + (struct xen_page_directory *)ptr; + + if (grefs_left <= XEN_NUM_GREFS_PER_PAGE) { + to_copy = grefs_left; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; + } else { + to_copy = XEN_NUM_GREFS_PER_PAGE; + page_dir->gref_dir_next_page = buf->grefs[i + 1]; + } + memcpy(&page_dir->gref, &buf->grefs[cur_gref], + to_copy * sizeof(grant_ref_t)); + ptr += PAGE_SIZE; + grefs_left -= to_copy; + cur_gref += to_copy; + } +} + +/** + * Grant references to the frontend's buffer pages. + * + * These will be shared with the backend, so it can + * access the buffer's data. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int guest_grant_refs_for_buffer(struct xen_front_pgdir_shbuf *buf, + grant_ref_t *priv_gref_head, + int gref_idx) +{ + int i, cur_ref, otherend_id; + + otherend_id = buf->xb_dev->otherend_id; + for (i = 0; i < buf->num_pages; i++) { + cur_ref = gnttab_claim_grant_reference(priv_gref_head); + if (cur_ref < 0) + return cur_ref; + + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, + xen_page_to_gfn(buf->pages[i]), + 0); + buf->grefs[gref_idx++] = cur_ref; + } + return 0; +} + +/** + * Grant all the references needed to share the buffer. + * + * Grant references to the page directory pages and, if + * needed, also to the pages of the shared buffer data. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int grant_references(struct xen_front_pgdir_shbuf *buf) +{ + grant_ref_t priv_gref_head; + int ret, i, j, cur_ref; + int otherend_id, num_pages_dir; + + ret = gnttab_alloc_grant_references(buf->num_grefs, &priv_gref_head); + if (ret < 0) { + dev_err(&buf->xb_dev->dev, + "Cannot allocate grant references\n"); + return ret; + } + + otherend_id = buf->xb_dev->otherend_id; + j = 0; + num_pages_dir = get_num_pages_dir(buf); + for (i = 0; i < num_pages_dir; i++) { + unsigned long frame; + + cur_ref = gnttab_claim_grant_reference(&priv_gref_head); + if (cur_ref < 0) + return cur_ref; + + frame = xen_page_to_gfn(virt_to_page(buf->directory + + PAGE_SIZE * i)); + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); + buf->grefs[j++] = cur_ref; + } + + if (buf->ops->grant_refs_for_buffer) { + ret = buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j); + if (ret) + return ret; + } + + gnttab_free_grant_references(priv_gref_head); + return 0; +} + +/** + * Allocate all required structures to mange shared buffer. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int alloc_storage(struct xen_front_pgdir_shbuf *buf) +{ + buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL); + if (!buf->grefs) + return -ENOMEM; + + buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL); + if (!buf->directory) + return -ENOMEM; + + return 0; +} + +/* + * For backend allocated buffers we don't need grant_refs_for_buffer + * as those grant references are allocated at backend side. + */ +static const struct xen_front_pgdir_shbuf_ops backend_ops = { + .calc_num_grefs = backend_calc_num_grefs, + .fill_page_dir = backend_fill_page_dir, + .map = backend_map, + .unmap = backend_unmap +}; + +/* + * For locally granted references we do not need to map/unmap + * the references. + */ +static const struct xen_front_pgdir_shbuf_ops local_ops = { + .calc_num_grefs = guest_calc_num_grefs, + .fill_page_dir = guest_fill_page_dir, + .grant_refs_for_buffer = guest_grant_refs_for_buffer, +}; + +/** + * Allocate a new instance of a shared buffer. + * + * \param cfg configuration to be used while allocating a new shared buffer. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_alloc(struct xen_front_pgdir_shbuf_cfg *cfg) +{ + struct xen_front_pgdir_shbuf *buf = cfg->pgdir; + int ret; + + if (cfg->be_alloc) + buf->ops = &backend_ops; + else + buf->ops = &local_ops; + buf->xb_dev = cfg->xb_dev; + buf->num_pages = cfg->num_pages; + buf->pages = cfg->pages; + + buf->ops->calc_num_grefs(buf); + + ret = alloc_storage(buf); + if (ret) + goto fail; + + ret = grant_references(buf); + if (ret) + goto fail; + + buf->ops->fill_page_dir(buf); + + return 0; + +fail: + xen_front_pgdir_shbuf_free(buf); + return ret; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_alloc); + +MODULE_DESCRIPTION("Xen frontend/backend page directory based " + "shared buffer handling"); +MODULE_AUTHOR("Oleksandr Andrushchenko"); +MODULE_LICENSE("GPL"); diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c @@ -106,7 +106,8 @@ static void pcistub_device_release(struct kref *kref) * is called from "unbind" which takes a device_lock mutex. */ __pci_reset_function_locked(dev); - if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state)) + if (dev_data && + pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state)) dev_info(&dev->dev, "Could not reload PCI state\n"); else pci_restore_state(dev); diff --git a/include/xen/interface/hvm/start_info.h b/include/xen/interface/hvm/start_info.h @@ -33,7 +33,7 @@ * | magic | Contains the magic value XEN_HVM_START_MAGIC_VALUE * | | ("xEn3" with the 0x80 bit of the "E" set). * 4 +----------------+ - * | version | Version of this structure. Current version is 0. New + * | version | Version of this structure. Current version is 1. New * | | versions are guaranteed to be backwards-compatible. * 8 +----------------+ * | flags | SIF_xxx flags. @@ -48,6 +48,15 @@ * 32 +----------------+ * | rsdp_paddr | Physical address of the RSDP ACPI data structure. * 40 +----------------+ + * | memmap_paddr | Physical address of the (optional) memory map. Only + * | | present in version 1 and newer of the structure. + * 48 +----------------+ + * | memmap_entries | Number of entries in the memory map table. Zero + * | | if there is no memory map being provided. Only + * | | present in version 1 and newer of the structure. + * 52 +----------------+ + * | reserved | Version 1 and newer only. + * 56 +----------------+ * * The layout of each entry in the module structure is the following: * @@ -62,14 +71,52 @@ * | reserved | * 32 +----------------+ * + * The layout of each entry in the memory map table is as follows: + * + * 0 +----------------+ + * | addr | Base address + * 8 +----------------+ + * | size | Size of mapping in bytes + * 16 +----------------+ + * | type | Type of mapping as defined between the hypervisor + * | | and guest. See XEN_HVM_MEMMAP_TYPE_* values below. + * 20 +----------------| + * | reserved | + * 24 +----------------+ + * * The address and sizes are always a 64bit little endian unsigned integer. * * NB: Xen on x86 will always try to place all the data below the 4GiB * boundary. + * + * Version numbers of the hvm_start_info structure have evolved like this: + * + * Version 0: Initial implementation. + * + * Version 1: Added the memmap_paddr/memmap_entries fields (plus 4 bytes of + * padding) to the end of the hvm_start_info struct. These new + * fields can be used to pass a memory map to the guest. The + * memory map is optional and so guests that understand version 1 + * of the structure must check that memmap_entries is non-zero + * before trying to read the memory map. */ #define XEN_HVM_START_MAGIC_VALUE 0x336ec578 /* + * The values used in the type field of the memory map table entries are + * defined below and match the Address Range Types as defined in the "System + * Address Map Interfaces" section of the ACPI Specification. Please refer to + * section 15 in version 6.2 of the ACPI spec: http://uefi.org/specifications + */ +#define XEN_HVM_MEMMAP_TYPE_RAM 1 +#define XEN_HVM_MEMMAP_TYPE_RESERVED 2 +#define XEN_HVM_MEMMAP_TYPE_ACPI 3 +#define XEN_HVM_MEMMAP_TYPE_NVS 4 +#define XEN_HVM_MEMMAP_TYPE_UNUSABLE 5 +#define XEN_HVM_MEMMAP_TYPE_DISABLED 6 +#define XEN_HVM_MEMMAP_TYPE_PMEM 7 + +/* * C representation of the x86/HVM start info layout. * * The canonical definition of this layout is above, this is just a way to @@ -86,6 +133,13 @@ struct hvm_start_info { uint64_t cmdline_paddr; /* Physical address of the command line. */ uint64_t rsdp_paddr; /* Physical address of the RSDP ACPI data */ /* structure. */ + /* All following fields only present in version 1 and newer */ + uint64_t memmap_paddr; /* Physical address of an array of */ + /* hvm_memmap_table_entry. */ + uint32_t memmap_entries; /* Number of entries in the memmap table. */ + /* Value will be zero if there is no memory */ + /* map being provided. */ + uint32_t reserved; /* Must be zero. */ }; struct hvm_modlist_entry { @@ -95,4 +149,11 @@ struct hvm_modlist_entry { uint64_t reserved; }; +struct hvm_memmap_table_entry { + uint64_t addr; /* Base address of the memory region */ + uint64_t size; /* Size of the memory region in bytes */ + uint32_t type; /* Mapping type */ + uint32_t reserved; /* Must be zero for Version 1. */ +}; + #endif /* __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__ */ diff --git a/include/xen/xen-front-pgdir-shbuf.h b/include/xen/xen-front-pgdir-shbuf.h @@ -0,0 +1,89 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ + +/* + * Xen frontend/backend page directory based shared buffer + * helper module. + * + * Copyright (C) 2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#ifndef __XEN_FRONT_PGDIR_SHBUF_H_ +#define __XEN_FRONT_PGDIR_SHBUF_H_ + +#include <linux/kernel.h> + +#include <xen/grant_table.h> + +struct xen_front_pgdir_shbuf_ops; + +struct xen_front_pgdir_shbuf { + /* + * Number of references granted for the backend use: + * + * - for frontend allocated/imported buffers this holds the number + * of grant references for the page directory and the pages + * of the buffer + * + * - for the buffer provided by the backend this only holds the number + * of grant references for the page directory itself as grant + * references for the buffer will be provided by the backend. + */ + int num_grefs; + grant_ref_t *grefs; + /* Page directory backing storage. */ + u8 *directory; + + /* + * Number of pages for the shared buffer itself (excluding the page + * directory). + */ + int num_pages; + /* + * Backing storage of the shared buffer: these are the pages being + * shared. + */ + struct page **pages; + + struct xenbus_device *xb_dev; + + /* These are the ops used internally depending on be_alloc mode. */ + const struct xen_front_pgdir_shbuf_ops *ops; + + /* Xen map handles for the buffer allocated by the backend. */ + grant_handle_t *backend_map_handles; +}; + +struct xen_front_pgdir_shbuf_cfg { + struct xenbus_device *xb_dev; + + /* Number of pages of the buffer backing storage. */ + int num_pages; + /* Pages of the buffer to be shared. */ + struct page **pages; + + /* + * This is allocated outside because there are use-cases when + * the buffer structure is allocated as a part of a bigger one. + */ + struct xen_front_pgdir_shbuf *pgdir; + /* + * Mode of grant reference sharing: if set then backend will share + * grant references to the buffer with the frontend. + */ + int be_alloc; +}; + +int xen_front_pgdir_shbuf_alloc(struct xen_front_pgdir_shbuf_cfg *cfg); + +grant_ref_t +xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf); + +int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf); + +int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf); + +void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_shbuf *buf); + +#endif /* __XEN_FRONT_PGDIR_SHBUF_H_ */ diff --git a/include/xen/xen.h b/include/xen/xen.h @@ -29,6 +29,9 @@ extern bool xen_pvh; extern uint32_t xen_start_flags; +#include <xen/interface/hvm/start_info.h> +extern struct hvm_start_info pvh_start_info; + #ifdef CONFIG_XEN_DOM0 #include <xen/interface/xen.h> #include <asm/xen/hypervisor.h> diff --git a/sound/xen/Kconfig b/sound/xen/Kconfig @@ -5,6 +5,7 @@ config SND_XEN_FRONTEND depends on XEN select SND_PCM select XEN_XENBUS_FRONTEND + select XEN_FRONT_PGDIR_SHBUF help Choose this option if you want to enable a para-virtualized frontend sound driver for Xen guest OSes. diff --git a/sound/xen/Makefile b/sound/xen/Makefile @@ -3,7 +3,6 @@ snd_xen_front-objs := xen_snd_front.o \ xen_snd_front_cfg.o \ xen_snd_front_evtchnl.o \ - xen_snd_front_shbuf.o \ xen_snd_front_alsa.o obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c @@ -16,12 +16,12 @@ #include <xen/xen.h> #include <xen/xenbus.h> +#include <xen/xen-front-pgdir-shbuf.h> #include <xen/interface/io/sndif.h> #include "xen_snd_front.h" #include "xen_snd_front_alsa.h" #include "xen_snd_front_evtchnl.h" -#include "xen_snd_front_shbuf.h" static struct xensnd_req * be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8 operation) @@ -82,7 +82,7 @@ int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl, } int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl, - struct xen_snd_front_shbuf *sh_buf, + struct xen_front_pgdir_shbuf *shbuf, u8 format, unsigned int channels, unsigned int rate, u32 buffer_sz, u32 period_sz) @@ -99,7 +99,8 @@ int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl, req->op.open.pcm_rate = rate; req->op.open.buffer_sz = buffer_sz; req->op.open.period_sz = period_sz; - req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf); + req->op.open.gref_directory = + xen_front_pgdir_shbuf_get_dir_start(shbuf); mutex_unlock(&evtchnl->ring_io_lock); ret = be_stream_do_io(evtchnl); diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h @@ -16,7 +16,7 @@ struct xen_snd_front_card_info; struct xen_snd_front_evtchnl; struct xen_snd_front_evtchnl_pair; -struct xen_snd_front_shbuf; +struct xen_front_pgdir_shbuf; struct xensnd_query_hw_param; struct xen_snd_front_info { @@ -35,7 +35,7 @@ int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl, struct xensnd_query_hw_param *hw_param_resp); int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl, - struct xen_snd_front_shbuf *sh_buf, + struct xen_front_pgdir_shbuf *shbuf, u8 format, unsigned int channels, unsigned int rate, u32 buffer_sz, u32 period_sz); diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c @@ -15,17 +15,24 @@ #include <sound/pcm_params.h> #include <xen/xenbus.h> +#include <xen/xen-front-pgdir-shbuf.h> #include "xen_snd_front.h" #include "xen_snd_front_alsa.h" #include "xen_snd_front_cfg.h" #include "xen_snd_front_evtchnl.h" -#include "xen_snd_front_shbuf.h" struct xen_snd_front_pcm_stream_info { struct xen_snd_front_info *front_info; struct xen_snd_front_evtchnl_pair *evt_pair; - struct xen_snd_front_shbuf sh_buf; + + /* This is the shared buffer with its backing storage. */ + struct xen_front_pgdir_shbuf shbuf; + u8 *buffer; + size_t buffer_sz; + int num_pages; + struct page **pages; + int index; bool is_open; @@ -214,12 +221,20 @@ static void stream_clear(struct xen_snd_front_pcm_stream_info *stream) stream->out_frames = 0; atomic_set(&stream->hw_ptr, 0); xen_snd_front_evtchnl_pair_clear(stream->evt_pair); - xen_snd_front_shbuf_clear(&stream->sh_buf); + memset(&stream->shbuf, 0, sizeof(stream->shbuf)); + stream->buffer = NULL; + stream->buffer_sz = 0; + stream->pages = NULL; + stream->num_pages = 0; } static void stream_free(struct xen_snd_front_pcm_stream_info *stream) { - xen_snd_front_shbuf_free(&stream->sh_buf); + xen_front_pgdir_shbuf_unmap(&stream->shbuf); + xen_front_pgdir_shbuf_free(&stream->shbuf); + if (stream->buffer) + free_pages_exact(stream->buffer, stream->buffer_sz); + kfree(stream->pages); stream_clear(stream); } @@ -421,10 +436,34 @@ static int alsa_close(struct snd_pcm_substream *substream) return 0; } +static int shbuf_setup_backstore(struct xen_snd_front_pcm_stream_info *stream, + size_t buffer_sz) +{ + int i; + + stream->buffer = alloc_pages_exact(stream->buffer_sz, GFP_KERNEL); + if (!stream->buffer) + return -ENOMEM; + + stream->buffer_sz = buffer_sz; + stream->num_pages = DIV_ROUND_UP(stream->buffer_sz, PAGE_SIZE); + stream->pages = kcalloc(stream->num_pages, sizeof(struct page *), + GFP_KERNEL); + if (!stream->pages) + return -ENOMEM; + + for (i = 0; i < stream->num_pages; i++) + stream->pages[i] = virt_to_page(stream->buffer + i * PAGE_SIZE); + + return 0; +} + static int alsa_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params) { struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); + struct xen_snd_front_info *front_info = stream->front_info; + struct xen_front_pgdir_shbuf_cfg buf_cfg; int ret; /* @@ -432,19 +471,32 @@ static int alsa_hw_params(struct snd_pcm_substream *substream, * so free the previously allocated shared buffer if any. */ stream_free(stream); + ret = shbuf_setup_backstore(stream, params_buffer_bytes(params)); + if (ret < 0) + goto fail; - ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev, - &stream->sh_buf, - params_buffer_bytes(params)); - if (ret < 0) { - stream_free(stream); - dev_err(&stream->front_info->xb_dev->dev, - "Failed to allocate buffers for stream with index %d\n", - stream->index); - return ret; - } + memset(&buf_cfg, 0, sizeof(buf_cfg)); + buf_cfg.xb_dev = front_info->xb_dev; + buf_cfg.pgdir = &stream->shbuf; + buf_cfg.num_pages = stream->num_pages; + buf_cfg.pages = stream->pages; + + ret = xen_front_pgdir_shbuf_alloc(&buf_cfg); + if (ret < 0) + goto fail; + + ret = xen_front_pgdir_shbuf_map(&stream->shbuf); + if (ret < 0) + goto fail; return 0; + +fail: + stream_free(stream); + dev_err(&front_info->xb_dev->dev, + "Failed to allocate buffers for stream with index %d\n", + stream->index); + return ret; } static int alsa_hw_free(struct snd_pcm_substream *substream) @@ -476,7 +528,7 @@ static int alsa_prepare(struct snd_pcm_substream *substream) sndif_format = ret; ret = xen_snd_front_stream_prepare(&stream->evt_pair->req, - &stream->sh_buf, + &stream->shbuf, sndif_format, runtime->channels, runtime->rate, @@ -556,10 +608,10 @@ static int alsa_pb_copy_user(struct snd_pcm_substream *substream, { struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); - if (unlikely(pos + count > stream->sh_buf.buffer_sz)) + if (unlikely(pos + count > stream->buffer_sz)) return -EINVAL; - if (copy_from_user(stream->sh_buf.buffer + pos, src, count)) + if (copy_from_user(stream->buffer + pos, src, count)) return -EFAULT; return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count); @@ -571,10 +623,10 @@ static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream, { struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); - if (unlikely(pos + count > stream->sh_buf.buffer_sz)) + if (unlikely(pos + count > stream->buffer_sz)) return -EINVAL; - memcpy(stream->sh_buf.buffer + pos, src, count); + memcpy(stream->buffer + pos, src, count); return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count); } @@ -586,14 +638,14 @@ static int alsa_cap_copy_user(struct snd_pcm_substream *substream, struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); int ret; - if (unlikely(pos + count > stream->sh_buf.buffer_sz)) + if (unlikely(pos + count > stream->buffer_sz)) return -EINVAL; ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count); if (ret < 0) return ret; - return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ? + return copy_to_user(dst, stream->buffer + pos, count) ? -EFAULT : 0; } @@ -604,14 +656,14 @@ static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream, struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); int ret; - if (unlikely(pos + count > stream->sh_buf.buffer_sz)) + if (unlikely(pos + count > stream->buffer_sz)) return -EINVAL; ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count); if (ret < 0) return ret; - memcpy(dst, stream->sh_buf.buffer + pos, count); + memcpy(dst, stream->buffer + pos, count); return 0; } @@ -622,10 +674,10 @@ static int alsa_pb_fill_silence(struct snd_pcm_substream *substream, { struct xen_snd_front_pcm_stream_info *stream = stream_get(substream); - if (unlikely(pos + count > stream->sh_buf.buffer_sz)) + if (unlikely(pos + count > stream->buffer_sz)) return -EINVAL; - memset(stream->sh_buf.buffer + pos, 0, count); + memset(stream->buffer + pos, 0, count); return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count); } diff --git a/sound/xen/xen_snd_front_shbuf.c b/sound/xen/xen_snd_front_shbuf.c @@ -1,194 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 OR MIT - -/* - * Xen para-virtual sound device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> - */ - -#include <linux/kernel.h> -#include <xen/xen.h> -#include <xen/xenbus.h> - -#include "xen_snd_front_shbuf.h" - -grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf) -{ - if (!buf->grefs) - return GRANT_INVALID_REF; - - return buf->grefs[0]; -} - -void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf) -{ - memset(buf, 0, sizeof(*buf)); -} - -void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf) -{ - int i; - - if (buf->grefs) { - for (i = 0; i < buf->num_grefs; i++) - if (buf->grefs[i] != GRANT_INVALID_REF) - gnttab_end_foreign_access(buf->grefs[i], - 0, 0UL); - kfree(buf->grefs); - } - kfree(buf->directory); - free_pages_exact(buf->buffer, buf->buffer_sz); - xen_snd_front_shbuf_clear(buf); -} - -/* - * number of grant references a page can hold with respect to the - * xensnd_page_directory header - */ -#define XENSND_NUM_GREFS_PER_PAGE ((XEN_PAGE_SIZE - \ - offsetof(struct xensnd_page_directory, gref)) / \ - sizeof(grant_ref_t)) - -static void fill_page_dir(struct xen_snd_front_shbuf *buf, - int num_pages_dir) -{ - struct xensnd_page_directory *page_dir; - unsigned char *ptr; - int i, cur_gref, grefs_left, to_copy; - - ptr = buf->directory; - grefs_left = buf->num_grefs - num_pages_dir; - /* - * skip grant references at the beginning, they are for pages granted - * for the page directory itself - */ - cur_gref = num_pages_dir; - for (i = 0; i < num_pages_dir; i++) { - page_dir = (struct xensnd_page_directory *)ptr; - if (grefs_left <= XENSND_NUM_GREFS_PER_PAGE) { - to_copy = grefs_left; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; - } else { - to_copy = XENSND_NUM_GREFS_PER_PAGE; - page_dir->gref_dir_next_page = buf->grefs[i + 1]; - } - - memcpy(&page_dir->gref, &buf->grefs[cur_gref], - to_copy * sizeof(grant_ref_t)); - - ptr += XEN_PAGE_SIZE; - grefs_left -= to_copy; - cur_gref += to_copy; - } -} - -static int grant_references(struct xenbus_device *xb_dev, - struct xen_snd_front_shbuf *buf, - int num_pages_dir, int num_pages_buffer, - int num_grefs) -{ - grant_ref_t priv_gref_head; - unsigned long frame; - int ret, i, j, cur_ref; - int otherend_id; - - ret = gnttab_alloc_grant_references(num_grefs, &priv_gref_head); - if (ret) - return ret; - - buf->num_grefs = num_grefs; - otherend_id = xb_dev->otherend_id; - j = 0; - - for (i = 0; i < num_pages_dir; i++) { - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) { - ret = cur_ref; - goto fail; - } - - frame = xen_page_to_gfn(virt_to_page(buf->directory + - XEN_PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - for (i = 0; i < num_pages_buffer; i++) { - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) { - ret = cur_ref; - goto fail; - } - - frame = xen_page_to_gfn(virt_to_page(buf->buffer + - XEN_PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - gnttab_free_grant_references(priv_gref_head); - fill_page_dir(buf, num_pages_dir); - return 0; - -fail: - gnttab_free_grant_references(priv_gref_head); - return ret; -} - -static int alloc_int_buffers(struct xen_snd_front_shbuf *buf, - int num_pages_dir, int num_pages_buffer, - int num_grefs) -{ - buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL); - if (!buf->grefs) - return -ENOMEM; - - buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL); - if (!buf->directory) - goto fail; - - buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE; - buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL); - if (!buf->buffer) - goto fail; - - return 0; - -fail: - kfree(buf->grefs); - buf->grefs = NULL; - kfree(buf->directory); - buf->directory = NULL; - return -ENOMEM; -} - -int xen_snd_front_shbuf_alloc(struct xenbus_device *xb_dev, - struct xen_snd_front_shbuf *buf, - unsigned int buffer_sz) -{ - int num_pages_buffer, num_pages_dir, num_grefs; - int ret; - - xen_snd_front_shbuf_clear(buf); - - num_pages_buffer = DIV_ROUND_UP(buffer_sz, XEN_PAGE_SIZE); - /* number of pages the page directory consumes itself */ - num_pages_dir = DIV_ROUND_UP(num_pages_buffer, - XENSND_NUM_GREFS_PER_PAGE); - num_grefs = num_pages_buffer + num_pages_dir; - - ret = alloc_int_buffers(buf, num_pages_dir, - num_pages_buffer, num_grefs); - if (ret < 0) - return ret; - - ret = grant_references(xb_dev, buf, num_pages_dir, num_pages_buffer, - num_grefs); - if (ret < 0) - return ret; - - fill_page_dir(buf, num_pages_dir); - return 0; -} diff --git a/sound/xen/xen_snd_front_shbuf.h b/sound/xen/xen_snd_front_shbuf.h @@ -1,36 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 OR MIT */ - -/* - * Xen para-virtual sound device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> - */ - -#ifndef __XEN_SND_FRONT_SHBUF_H -#define __XEN_SND_FRONT_SHBUF_H - -#include <xen/grant_table.h> - -#include "xen_snd_front_evtchnl.h" - -struct xen_snd_front_shbuf { - int num_grefs; - grant_ref_t *grefs; - u8 *directory; - u8 *buffer; - size_t buffer_sz; -}; - -grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf); - -int xen_snd_front_shbuf_alloc(struct xenbus_device *xb_dev, - struct xen_snd_front_shbuf *buf, - unsigned int buffer_sz); - -void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf); - -void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf); - -#endif /* __XEN_SND_FRONT_SHBUF_H */