The pci-shmem emulated device ("ivshmem") was created by QEMU for
cross-VM data sharing. The only Linux driver that uses this device is
the Android Virtual System on a Chip staging driver, which also mentions
a character device driver implemented on top of shmem, which was removed
from Linux.
On the kvmtool side, the only commits touching the pci-shmem device
since it was introduced in 2012 were made when refactoring various
kvmtool subsystems. Let's remove the maintenance burden on the kvmtool
maintainers and remove this unused device.
Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx>
Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
---
Makefile | 1 -
builtin-run.c | 5 -
hw/pci-shmem.c | 400 ----------------------------------------
include/kvm/pci-shmem.h | 32 ----
4 files changed, 438 deletions(-)
delete mode 100644 hw/pci-shmem.c
delete mode 100644 include/kvm/pci-shmem.h
diff --git a/Makefile b/Makefile
index 33eddcbb4d66..f75413e74819 100644
--- a/Makefile
+++ b/Makefile
@@ -99,7 +99,6 @@ OBJS += util/read-write.o
OBJS += util/util.o
OBJS += virtio/9p.o
OBJS += virtio/9p-pdu.o
-OBJS += hw/pci-shmem.o
OBJS += kvm-ipc.o
OBJS += builtin-sandbox.o
OBJS += virtio/mmio.o
diff --git a/builtin-run.c b/builtin-run.c
index f8dc6c7229b0..9cb8c75300eb 100644
--- a/builtin-run.c
+++ b/builtin-run.c
@@ -31,7 +31,6 @@
#include "kvm/sdl.h"
#include "kvm/vnc.h"
#include "kvm/guest_compat.h"
-#include "kvm/pci-shmem.h"
#include "kvm/kvm-ipc.h"
#include "kvm/builtin-debug.h"
@@ -99,10 +98,6 @@ void kvm_run_set_wrapper_sandbox(void)
OPT_INTEGER('c', "cpus", &(cfg)->nrcpus, "Number of CPUs"), \
OPT_U64('m', "mem", &(cfg)->ram_size, "Virtual machine memory" \
" size in MiB."), \
- OPT_CALLBACK('\0', "shmem", NULL, \
- "[pci:]<addr>:<size>[:handle=<handle>][:create]", \
- "Share host shmem with guest via pci device", \
- shmem_parser, NULL), \
OPT_CALLBACK('d', "disk", kvm, "image or rootfs_dir", "Disk " \
" image or rootfs directory", img_name_parser, \
kvm), \
diff --git a/hw/pci-shmem.c b/hw/pci-shmem.c
deleted file mode 100644
index f92bc75544d7..000000000000
--- a/hw/pci-shmem.c
+++ /dev/null
@@ -1,400 +0,0 @@
-#include "kvm/devices.h"
-#include "kvm/pci-shmem.h"
-#include "kvm/virtio-pci-dev.h"
-#include "kvm/irq.h"
-#include "kvm/kvm.h"
-#include "kvm/pci.h"
-#include "kvm/util.h"
-#include "kvm/ioport.h"
-#include "kvm/ioeventfd.h"
-
-#include <linux/kvm.h>
-#include <linux/byteorder.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-
-#define MB_SHIFT (20)
-#define KB_SHIFT (10)
-#define GB_SHIFT (30)
-
-static struct pci_device_header pci_shmem_pci_device = {
- .vendor_id = cpu_to_le16(PCI_VENDOR_ID_REDHAT_QUMRANET),
- .device_id = cpu_to_le16(0x1110),
- .header_type = PCI_HEADER_TYPE_NORMAL,
- .class[2] = 0xFF, /* misc pci device */
- .status = cpu_to_le16(PCI_STATUS_CAP_LIST),
- .capabilities = (void *)&pci_shmem_pci_device.msix - (void *)&pci_shmem_pci_device,
- .msix.cap = PCI_CAP_ID_MSIX,
- .msix.ctrl = cpu_to_le16(1),
- .msix.table_offset = cpu_to_le32(1), /* Use BAR 1 */
- .msix.pba_offset = cpu_to_le32(0x1001), /* Use BAR 1 */
-};
-
-static struct device_header pci_shmem_device = {
- .bus_type = DEVICE_BUS_PCI,
- .data = &pci_shmem_pci_device,
-};
-
-/* registers for the Inter-VM shared memory device */
-enum ivshmem_registers {
- INTRMASK = 0,
- INTRSTATUS = 4,
- IVPOSITION = 8,
- DOORBELL = 12,
-};
-
-static struct shmem_info *shmem_region;
-static u16 ivshmem_registers;
-static int local_fd;
-static u32 local_id;
-static u64 msix_block;
-static u64 msix_pba;
-static struct msix_table msix_table[2];
-
-int pci_shmem__register_mem(struct shmem_info *si)
-{
- if (!shmem_region) {
- shmem_region = si;
- } else {
- pr_warning("only single shmem currently avail. ignoring.\n");
- free(si);
- }
- return 0;
-}
-
-static bool shmem_pci__io_in(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size)
-{
- u16 offset = port - ivshmem_registers;
-
- switch (offset) {
- case INTRMASK:
- break;
- case INTRSTATUS:
- break;
- case IVPOSITION:
- ioport__write32(data, local_id);
- break;
- case DOORBELL:
- break;
- };
-
- return true;
-}
-
-static bool shmem_pci__io_out(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size)
-{
- u16 offset = port - ivshmem_registers;
-
- switch (offset) {
- case INTRMASK:
- break;
- case INTRSTATUS:
- break;
- case IVPOSITION:
- break;
- case DOORBELL:
- break;
- };
-
- return true;
-}
-
-static struct ioport_operations shmem_pci__io_ops = {
- .io_in = shmem_pci__io_in,
- .io_out = shmem_pci__io_out,
-};
-
-static void callback_mmio_msix(struct kvm_cpu *vcpu, u64 addr, u8 *data, u32 len, u8 is_write, void *ptr)
-{
- void *mem;
-
- if (addr - msix_block < 0x1000)
- mem = &msix_table;
- else
- mem = &msix_pba;
-
- if (is_write)
- memcpy(mem + addr - msix_block, data, len);
- else
- memcpy(data, mem + addr - msix_block, len);
-}
-
-/*
- * Return an irqfd which can be used by other guests to signal this guest
- * whenever they need to poke it
- */
-int pci_shmem__get_local_irqfd(struct kvm *kvm)
-{
- int fd, gsi, r;
-
- if (local_fd == 0) {
- fd = eventfd(0, 0);
- if (fd < 0)
- return fd;
-
- if (pci_shmem_pci_device.msix.ctrl & cpu_to_le16(PCI_MSIX_FLAGS_ENABLE)) {
- gsi = irq__add_msix_route(kvm, &msix_table[0].msg,
- pci_shmem_device.dev_num << 3);
- if (gsi < 0)
- return gsi;
- } else {
- gsi = pci_shmem_pci_device.irq_line;
- }
-
- r = irq__add_irqfd(kvm, gsi, fd, -1);
- if (r < 0)
- return r;
-
- local_fd = fd;
- }
-
- return local_fd;
-}
-
-/*
- * Connect a new client to ivshmem by adding the appropriate datamatch
- * to the DOORBELL
- */
-int pci_shmem__add_client(struct kvm *kvm, u32 id, int fd)
-{
- struct kvm_ioeventfd ioevent;
-
- ioevent = (struct kvm_ioeventfd) {
- .addr = ivshmem_registers + DOORBELL,
- .len = sizeof(u32),
- .datamatch = id,
- .fd = fd,
- .flags = KVM_IOEVENTFD_FLAG_PIO | KVM_IOEVENTFD_FLAG_DATAMATCH,
- };
-
- return ioctl(kvm->vm_fd, KVM_IOEVENTFD, &ioevent);
-}
-
-/*
- * Remove a client connected to ivshmem by removing the appropriate datamatch
- * from the DOORBELL
- */
-int pci_shmem__remove_client(struct kvm *kvm, u32 id)
-{
- struct kvm_ioeventfd ioevent;
-
- ioevent = (struct kvm_ioeventfd) {
- .addr = ivshmem_registers + DOORBELL,
- .len = sizeof(u32),
- .datamatch = id,
- .flags = KVM_IOEVENTFD_FLAG_PIO
- | KVM_IOEVENTFD_FLAG_DATAMATCH
- | KVM_IOEVENTFD_FLAG_DEASSIGN,
- };
-
- return ioctl(kvm->vm_fd, KVM_IOEVENTFD, &ioevent);
-}
-
-static void *setup_shmem(const char *key, size_t len, int creating)
-{
- int fd;
- int rtn;
- void *mem;
- int flag = O_RDWR;
-
- if (creating)
- flag |= O_CREAT;
-
- fd = shm_open(key, flag, S_IRUSR | S_IWUSR);
- if (fd < 0) {
- pr_warning("Failed to open shared memory file %s\n", key);
- return NULL;
- }
-
- if (creating) {
- rtn = ftruncate(fd, (off_t) len);
- if (rtn < 0)
- pr_warning("Can't ftruncate(fd,%zu)\n", len);
- }
- mem = mmap(NULL, len,
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_NORESERVE, fd, 0);
- if (mem == MAP_FAILED) {
- pr_warning("Failed to mmap shared memory file");
- mem = NULL;
- }
- close(fd);
-
- return mem;
-}
-
-int shmem_parser(const struct option *opt, const char *arg, int unset)
-{
- const u64 default_size = SHMEM_DEFAULT_SIZE;
- const u64 default_phys_addr = SHMEM_DEFAULT_ADDR;
- const char *default_handle = SHMEM_DEFAULT_HANDLE;
- struct shmem_info *si = malloc(sizeof(struct shmem_info));
- u64 phys_addr;
- u64 size;
- char *handle = NULL;
- int create = 0;
- const char *p = arg;
- char *next;
- int base = 10;
- int verbose = 0;
-
- const int skip_pci = strlen("pci:");
- if (verbose)
- pr_info("shmem_parser(%p,%s,%d)", opt, arg, unset);
- /* parse out optional addr family */
- if (strcasestr(p, "pci:")) {
- p += skip_pci;
- } else if (strcasestr(p, "mem:")) {
- die("I can't add to E820 map yet.\n");
- }
- /* parse out physical addr */
- base = 10;
- if (strcasestr(p, "0x"))
- base = 16;
- phys_addr = strtoll(p, &next, base);
- if (next == p && phys_addr == 0) {
- pr_info("shmem: no physical addr specified, using default.");
- phys_addr = default_phys_addr;
- }
- if (*next != ':' && *next != '\0')
- die("shmem: unexpected chars after phys addr.\n");
- if (*next == '\0')
- p = next;
- else
- p = next + 1;
- /* parse out size */
- base = 10;
- if (strcasestr(p, "0x"))
- base = 16;
- size = strtoll(p, &next, base);
- if (next == p && size == 0) {
- pr_info("shmem: no size specified, using default.");
- size = default_size;
- }
- /* look for [KMGkmg][Bb]* uses base 2. */
- int skip_B = 0;
- if (strspn(next, "KMGkmg")) { /* might have a prefix */
- if (*(next + 1) == 'B' || *(next + 1) == 'b')
- skip_B = 1;
- switch (*next) {
- case 'K':
- case 'k':
- size = size << KB_SHIFT;
- break;
- case 'M':
- case 'm':
- size = size << MB_SHIFT;
- break;
- case 'G':
- case 'g':
- size = size << GB_SHIFT;
- break;
- default:
- die("shmem: bug in detecting size prefix.");
- break;
- }
- next += 1 + skip_B;
- }
- if (*next != ':' && *next != '\0') {
- die("shmem: unexpected chars after phys size. <%c><%c>\n",
- *next, *p);
- }
- if (*next == '\0')
- p = next;
- else
- p = next + 1;
- /* parse out optional shmem handle */
- const int skip_handle = strlen("handle=");
- next = strcasestr(p, "handle=");
- if (*p && next) {
- if (p != next)
- die("unexpected chars before handle\n");
- p += skip_handle;
- next = strchrnul(p, ':');
- if (next - p) {
- handle = malloc(next - p + 1);
- strncpy(handle, p, next - p);
- handle[next - p] = '\0'; /* just in case. */
- }
- if (*next == '\0')
- p = next;
- else
- p = next + 1;
- }
- /* parse optional create flag to see if we should create shm seg. */
- if (*p && strcasestr(p, "create")) {
- create = 1;
- p += strlen("create");
- }
- if (*p != '\0')
- die("shmem: unexpected trailing chars\n");
- if (handle == NULL) {
- handle = malloc(strlen(default_handle) + 1);
- strcpy(handle, default_handle);
- }
- if (verbose) {
- pr_info("shmem: phys_addr = %llx",
- (unsigned long long)phys_addr);
- pr_info("shmem: size = %llx", (unsigned long long)size);
- pr_info("shmem: handle = %s", handle);
- pr_info("shmem: create = %d", create);
- }
-
- si->phys_addr = phys_addr;
- si->size = size;
- si->handle = handle;
- si->create = create;
- pci_shmem__register_mem(si); /* ownership of si, etc. passed on. */
- return 0;
-}
-
-int pci_shmem__init(struct kvm *kvm)
-{
- char *mem;
- int r;
-
- if (shmem_region == NULL)
- return 0;
-
- /* Register MMIO space for MSI-X */
- r = ioport__register(kvm, IOPORT_EMPTY, &shmem_pci__io_ops, IOPORT_SIZE, NULL);
- if (r < 0)
- return r;
- ivshmem_registers = (u16)r;
-
- msix_block = pci_get_io_space_block(0x1010);
- kvm__register_mmio(kvm, msix_block, 0x1010, false, callback_mmio_msix, NULL);
-
- /*
- * This registers 3 BARs:
- *
- * 0 - ivshmem registers
- * 1 - MSI-X MMIO space
- * 2 - Shared memory block
- */
- pci_shmem_pci_device.bar[0] = cpu_to_le32(ivshmem_registers | PCI_BASE_ADDRESS_SPACE_IO);
- pci_shmem_pci_device.bar_size[0] = shmem_region->size;
- pci_shmem_pci_device.bar[1] = cpu_to_le32(msix_block | PCI_BASE_ADDRESS_SPACE_MEMORY);
- pci_shmem_pci_device.bar_size[1] = 0x1010;
- pci_shmem_pci_device.bar[2] = cpu_to_le32(shmem_region->phys_addr | PCI_BASE_ADDRESS_SPACE_MEMORY);
- pci_shmem_pci_device.bar_size[2] = shmem_region->size;
-
- device__register(&pci_shmem_device);
-
- /* Open shared memory and plug it into the guest */
- mem = setup_shmem(shmem_region->handle, shmem_region->size,
- shmem_region->create);
- if (mem == NULL)
- return -EINVAL;
-
- kvm__register_dev_mem(kvm, shmem_region->phys_addr, shmem_region->size,
- mem);
- return 0;
-}
-dev_init(pci_shmem__init);
-
-int pci_shmem__exit(struct kvm *kvm)
-{
- return 0;
-}
-dev_exit(pci_shmem__exit);
diff --git a/include/kvm/pci-shmem.h b/include/kvm/pci-shmem.h
deleted file mode 100644
index 6cff2b85bfd3..000000000000
--- a/include/kvm/pci-shmem.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef KVM__PCI_SHMEM_H
-#define KVM__PCI_SHMEM_H
-
-#include <linux/types.h>
-#include <linux/list.h>
-
-#include "kvm/parse-options.h"
-
-#define SHMEM_DEFAULT_SIZE (16 << MB_SHIFT)
-#define SHMEM_DEFAULT_ADDR (0xc8000000)
-#define SHMEM_DEFAULT_HANDLE "/kvm_shmem"
-
-struct kvm;
-struct shmem_info;
-
-struct shmem_info {
- u64 phys_addr;
- u64 size;
- char *handle;
- int create;
-};
-
-int pci_shmem__init(struct kvm *kvm);
-int pci_shmem__exit(struct kvm *kvm);
-int pci_shmem__register_mem(struct shmem_info *si);
-int shmem_parser(const struct option *opt, const char *arg, int unset);
-
-int pci_shmem__get_local_irqfd(struct kvm *kvm);
-int pci_shmem__add_client(struct kvm *kvm, u32 id, int fd);
-int pci_shmem__remove_client(struct kvm *kvm, u32 id);
-
-#endif
--
2.20.1
