diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 8073625371f5d22defae1efe6322a717201e8010..07060e5b58641cc008f41aa927c2e6043ab6afbb 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -59,6 +59,9 @@ struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
static __read_mostly unsigned int xen_events_irq;
+uint32_t xen_start_flags;
+EXPORT_SYMBOL(xen_start_flags);
+
int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
unsigned long addr,
xen_pfn_t *gfn, int nr,
@@ -293,9 +296,7 @@ void __init xen_early_init(void)
xen_setup_features();
if (xen_feature(XENFEAT_dom0))
- xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
- else
- xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
+ xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
if (!console_set_on_cmdline && !xen_initial_domain())
add_preferred_console("hvc", 0, NULL);
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index c9081c6671f0b7a05ecfaaf206e7e1ed2b1f456a..3b5318505c69c487f8cfc9c46c93c526197caef6 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -64,6 +64,13 @@ struct shared_info xen_dummy_shared_info;
__read_mostly int xen_have_vector_callback;
EXPORT_SYMBOL_GPL(xen_have_vector_callback);
+/*
+ * NB: needs to live in .data because it's used by xen_prepare_pvh which runs
+ * before clearing the bss.
+ */
+uint32_t xen_start_flags __attribute__((section(".data"))) = 0;
+EXPORT_SYMBOL(xen_start_flags);
+
/*
* Point at some empty memory to start with. We map the real shared_info
* page as soon as fixmap is up and running.
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 357969a3697cc7af6e08c12144ec06f43a8841ad..8d4e2e1ae60bc93d3391dfc8c12b10fc0557f242 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1203,6 +1203,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
return;
xen_domain_type = XEN_PV_DOMAIN;
+ xen_start_flags = xen_start_info->flags;
xen_setup_features();
diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index aa1c6a6831a94dd383e11c575a2a0c91f32136b5..c85d1a88f47693232369411588cfc19084086b25 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -97,6 +97,7 @@ void __init xen_prepare_pvh(void)
}
xen_pvh = 1;
+ xen_start_flags = pvh_start_info.flags;
msr = cpuid_ebx(xen_cpuid_base() + 2);
pfn = __pa(hypercall_page);
diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
index 36f59a1be7e9a60be61c2b1ba8f7468dfbd8c6c9..61389bdc7926690100fc0a38fc59e8b6a73853ab 100644
--- a/drivers/scsi/xen-scsifront.c
+++ b/drivers/scsi/xen-scsifront.c
@@ -654,10 +654,17 @@ static int scsifront_dev_reset_handler(struct scsi_cmnd *sc)
static int scsifront_sdev_configure(struct scsi_device *sdev)
{
struct vscsifrnt_info *info = shost_priv(sdev->host);
+ int err;
- if (info && current == info->curr)
- xenbus_printf(XBT_NIL, info->dev->nodename,
+ if (info && current == info->curr) {
+ err = xenbus_printf(XBT_NIL, info->dev->nodename,
info->dev_state_path, "%d", XenbusStateConnected);
+ if (err) {
+ xenbus_dev_error(info->dev, err,
+ "%s: writing dev_state_path", __func__);
+ return err;
+ }
+ }
return 0;
}
@@ -665,10 +672,15 @@ static int scsifront_sdev_configure(struct scsi_device *sdev)
static void scsifront_sdev_destroy(struct scsi_device *sdev)
{
struct vscsifrnt_info *info = shost_priv(sdev->host);
+ int err;
- if (info && current == info->curr)
- xenbus_printf(XBT_NIL, info->dev->nodename,
+ if (info && current == info->curr) {
+ err = xenbus_printf(XBT_NIL, info->dev->nodename,
info->dev_state_path, "%d", XenbusStateClosed);
+ if (err)
+ xenbus_dev_error(info->dev, err,
+ "%s: writing dev_state_path", __func__);
+ }
}
static struct scsi_host_template scsifront_sht = {
@@ -1003,9 +1015,12 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
if (scsi_add_device(info->host, chn, tgt, lun)) {
dev_err(&dev->dev, "scsi_add_device\n");
- xenbus_printf(XBT_NIL, dev->nodename,
+ err = xenbus_printf(XBT_NIL, dev->nodename,
info->dev_state_path,
"%d", XenbusStateClosed);
+ if (err)
+ xenbus_dev_error(dev, err,
+ "%s: writing dev_state_path", __func__);
}
break;
case VSCSIFRONT_OP_DEL_LUN:
@@ -1019,10 +1034,14 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
}
break;
case VSCSIFRONT_OP_READD_LUN:
- if (device_state == XenbusStateConnected)
- xenbus_printf(XBT_NIL, dev->nodename,
+ if (device_state == XenbusStateConnected) {
+ err = xenbus_printf(XBT_NIL, dev->nodename,
info->dev_state_path,
"%d", XenbusStateConnected);
+ if (err)
+ xenbus_dev_error(dev, err,
+ "%s: writing dev_state_path", __func__);
+ }
break;
default:
break;
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 451e833f593175886fd4fa6ae066860dad4cf95e..48b154276179f0269c7444e38d6717ac493a06d5 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -41,4 +41,4 @@ obj-$(CONFIG_XEN_PVCALLS_FRONTEND) += pvcalls-front.o
xen-evtchn-y := evtchn.o
xen-gntdev-y := gntdev.o
xen-gntalloc-y := gntalloc.o
-xen-privcmd-y := privcmd.o
+xen-privcmd-y := privcmd.o privcmd-buf.o
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 762378f1811cc9069dc6171edb55aaa3610b82fa..08e4af04d6f2c32850a049a83721933a82883b8c 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -628,8 +628,6 @@ static void __unbind_from_irq(unsigned int irq)
xen_irq_info_cleanup(info);
}
- BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
-
xen_free_irq(irq);
}
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 2473b0a9e6e41d5d51b47e318d7e3b26d81ec5f6..ba9f3eec2bd00f6f39eb952ed5815e7b45c9735e 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -799,7 +799,7 @@ int gnttab_alloc_pages(int nr_pages, struct page **pages)
return 0;
}
-EXPORT_SYMBOL(gnttab_alloc_pages);
+EXPORT_SYMBOL_GPL(gnttab_alloc_pages);
/**
* gnttab_free_pages - free pages allocated by gnttab_alloc_pages()
@@ -820,7 +820,7 @@ void gnttab_free_pages(int nr_pages, struct page **pages)
}
free_xenballooned_pages(nr_pages, pages);
}
-EXPORT_SYMBOL(gnttab_free_pages);
+EXPORT_SYMBOL_GPL(gnttab_free_pages);
/* Handling of paged out grant targets (GNTST_eagain) */
#define MAX_DELAY 256
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index 8835065029d34a150a91662bb4562b4a41be50ca..c93d8ef8df3483bbc393b2101c189120f844b634 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -289,8 +289,15 @@ static void sysrq_handler(struct xenbus_watch *watch, const char *path,
return;
}
- if (sysrq_key != '\0')
- xenbus_printf(xbt, "control", "sysrq", "%c", '\0');
+ if (sysrq_key != '\0') {
+ err = xenbus_printf(xbt, "control", "sysrq", "%c", '\0');
+ if (err) {
+ pr_err("%s: Error %d writing sysrq in control/sysrq\n",
+ __func__, err);
+ xenbus_transaction_end(xbt, 1);
+ return;
+ }
+ }
err = xenbus_transaction_end(xbt, 0);
if (err == -EAGAIN)
@@ -342,7 +349,12 @@ static int setup_shutdown_watcher(void)
continue;
snprintf(node, FEATURE_PATH_SIZE, "feature-%s",
shutdown_handlers[idx].command);
- xenbus_printf(XBT_NIL, "control", node, "%u", 1);
+ err = xenbus_printf(XBT_NIL, "control", node, "%u", 1);
+ if (err) {
+ pr_err("%s: Error %d writing %s\n", __func__,
+ err, node);
+ return err;
+ }
}
return 0;
diff --git a/drivers/xen/privcmd-buf.c b/drivers/xen/privcmd-buf.c
new file mode 100644
index 0000000000000000000000000000000000000000..df1ed37c3269ebd8170a21583676b80efe50a47f
--- /dev/null
+++ b/drivers/xen/privcmd-buf.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/******************************************************************************
+ * privcmd-buf.c
+ *
+ * Mmap of hypercall buffers.
+ *
+ * Copyright (c) 2018 Juergen Gross
+ */
+
+#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+
+#include "privcmd.h"
+
+MODULE_LICENSE("GPL");
+
+static unsigned int limit = 64;
+module_param(limit, uint, 0644);
+MODULE_PARM_DESC(limit, "Maximum number of pages that may be allocated by "
+ "the privcmd-buf device per open file");
+
+struct privcmd_buf_private {
+ struct mutex lock;
+ struct list_head list;
+ unsigned int allocated;
+};
+
+struct privcmd_buf_vma_private {
+ struct privcmd_buf_private *file_priv;
+ struct list_head list;
+ unsigned int users;
+ unsigned int n_pages;
+ struct page *pages[];
+};
+
+static int privcmd_buf_open(struct inode *ino, struct file *file)
+{
+ struct privcmd_buf_private *file_priv;
+
+ file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
+ if (!file_priv)
+ return -ENOMEM;
+
+ mutex_init(&file_priv->lock);
+ INIT_LIST_HEAD(&file_priv->list);
+
+ file->private_data = file_priv;
+
+ return 0;
+}
+
+static void privcmd_buf_vmapriv_free(struct privcmd_buf_vma_private *vma_priv)
+{
+ unsigned int i;
+
+ vma_priv->file_priv->allocated -= vma_priv->n_pages;
+
+ list_del(&vma_priv->list);
+
+ for (i = 0; i < vma_priv->n_pages; i++)
+ if (vma_priv->pages[i])
+ __free_page(vma_priv->pages[i]);
+
+ kfree(vma_priv);
+}
+
+static int privcmd_buf_release(struct inode *ino, struct file *file)
+{
+ struct privcmd_buf_private *file_priv = file->private_data;
+ struct privcmd_buf_vma_private *vma_priv;
+
+ mutex_lock(&file_priv->lock);
+
+ while (!list_empty(&file_priv->list)) {
+ vma_priv = list_first_entry(&file_priv->list,
+ struct privcmd_buf_vma_private,
+ list);
+ privcmd_buf_vmapriv_free(vma_priv);
+ }
+
+ mutex_unlock(&file_priv->lock);
+
+ kfree(file_priv);
+
+ return 0;
+}
+
+static void privcmd_buf_vma_open(struct vm_area_struct *vma)
+{
+ struct privcmd_buf_vma_private *vma_priv = vma->vm_private_data;
+
+ if (!vma_priv)
+ return;
+
+ mutex_lock(&vma_priv->file_priv->lock);
+ vma_priv->users++;
+ mutex_unlock(&vma_priv->file_priv->lock);
+}
+
+static void privcmd_buf_vma_close(struct vm_area_struct *vma)
+{
+ struct privcmd_buf_vma_private *vma_priv = vma->vm_private_data;
+ struct privcmd_buf_private *file_priv;
+
+ if (!vma_priv)
+ return;
+
+ file_priv = vma_priv->file_priv;
+
+ mutex_lock(&file_priv->lock);
+
+ vma_priv->users--;
+ if (!vma_priv->users)
+ privcmd_buf_vmapriv_free(vma_priv);
+
+ mutex_unlock(&file_priv->lock);
+}
+
+static vm_fault_t privcmd_buf_vma_fault(struct vm_fault *vmf)
+{
+ pr_debug("fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
+ vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end,
+ vmf->pgoff, (void *)vmf->address);
+
+ return VM_FAULT_SIGBUS;
+}
+
+static const struct vm_operations_struct privcmd_buf_vm_ops = {
+ .open = privcmd_buf_vma_open,
+ .close = privcmd_buf_vma_close,
+ .fault = privcmd_buf_vma_fault,
+};
+
+static int privcmd_buf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct privcmd_buf_private *file_priv = file->private_data;
+ struct privcmd_buf_vma_private *vma_priv;
+ unsigned long count = vma_pages(vma);
+ unsigned int i;
+ int ret = 0;
+
+ if (!(vma->vm_flags & VM_SHARED) || count > limit ||
+ file_priv->allocated + count > limit)
+ return -EINVAL;
+
+ vma_priv = kzalloc(sizeof(*vma_priv) + count * sizeof(void *),
+ GFP_KERNEL);
+ if (!vma_priv)
+ return -ENOMEM;
+
+ vma_priv->n_pages = count;
+ count = 0;
+ for (i = 0; i < vma_priv->n_pages; i++) {
+ vma_priv->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!vma_priv->pages[i])
+ break;
+ count++;
+ }
+
+ mutex_lock(&file_priv->lock);
+
+ file_priv->allocated += count;
+
+ vma_priv->file_priv = file_priv;
+ vma_priv->users = 1;
+
+ vma->vm_flags |= VM_IO | VM_DONTEXPAND;
+ vma->vm_ops = &privcmd_buf_vm_ops;
+ vma->vm_private_data = vma_priv;
+
+ list_add(&vma_priv->list, &file_priv->list);
+
+ if (vma_priv->n_pages != count)
+ ret = -ENOMEM;
+ else
+ for (i = 0; i < vma_priv->n_pages; i++) {
+ ret = vm_insert_page(vma, vma->vm_start + i * PAGE_SIZE,
+ vma_priv->pages[i]);
+ if (ret)
+ break;
+ }
+
+ if (ret)
+ privcmd_buf_vmapriv_free(vma_priv);
+
+ mutex_unlock(&file_priv->lock);
+
+ return ret;
+}
+
+const struct file_operations xen_privcmdbuf_fops = {
+ .owner = THIS_MODULE,
+ .open = privcmd_buf_open,
+ .release = privcmd_buf_release,
+ .mmap = privcmd_buf_mmap,
+};
+EXPORT_SYMBOL_GPL(xen_privcmdbuf_fops);
+
+struct miscdevice xen_privcmdbuf_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/hypercall",
+ .fops = &xen_privcmdbuf_fops,
+};
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index 8ae0349d9f0ae47036ed2b6b8e968230c1fdfb41..7e6e682104dc4e9a77d8149e2f4500ded81b41b8 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -1007,12 +1007,21 @@ static int __init privcmd_init(void)
pr_err("Could not register Xen privcmd device\n");
return err;
}
+
+ err = misc_register(&xen_privcmdbuf_dev);
+ if (err != 0) {
+ pr_err("Could not register Xen hypercall-buf device\n");
+ misc_deregister(&privcmd_dev);
+ return err;
+ }
+
return 0;
}
static void __exit privcmd_exit(void)
{
misc_deregister(&privcmd_dev);
+ misc_deregister(&xen_privcmdbuf_dev);
}
module_init(privcmd_init);
diff --git a/drivers/xen/privcmd.h b/drivers/xen/privcmd.h
index 14facaeed36fda1a1492aaa2a88a72bc8855c450..0dd9f8f67ee30efc849a7bdf2085036c0c0e84ab 100644
--- a/drivers/xen/privcmd.h
+++ b/drivers/xen/privcmd.h
@@ -1,3 +1,6 @@
#include <linux/fs.h>
extern const struct file_operations xen_privcmd_fops;
+extern const struct file_operations xen_privcmdbuf_fops;
+
+extern struct miscdevice xen_privcmdbuf_dev;
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index 7bc88fd43cfc84d05873893ef4ddec8307e76c2a..e2f3e8b0fba9ff160a7c82a37e64cf5fe0b3c8f0 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -1012,6 +1012,7 @@ static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
{
struct v2p_entry *entry;
unsigned long flags;
+ int err;
if (try) {
spin_lock_irqsave(&info->v2p_lock, flags);
@@ -1027,8 +1028,11 @@ static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
scsiback_del_translation_entry(info, vir);
}
} else if (!try) {
- xenbus_printf(XBT_NIL, info->dev->nodename, state,
+ err = xenbus_printf(XBT_NIL, info->dev->nodename, state,
"%d", XenbusStateClosed);
+ if (err)
+ xenbus_dev_error(info->dev, err,
+ "%s: writing %s", __func__, state);
}
}
@@ -1067,8 +1071,11 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent);
val = xenbus_read(XBT_NIL, dev->nodename, str, NULL);
if (IS_ERR(val)) {
- xenbus_printf(XBT_NIL, dev->nodename, state,
+ err = xenbus_printf(XBT_NIL, dev->nodename, state,
"%d", XenbusStateClosed);
+ if (err)
+ xenbus_dev_error(info->dev, err,
+ "%s: writing %s", __func__, state);
return;
}
strlcpy(phy, val, VSCSI_NAMELEN);
@@ -1079,8 +1086,11 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u",
&vir.hst, &vir.chn, &vir.tgt, &vir.lun);
if (XENBUS_EXIST_ERR(err)) {
- xenbus_printf(XBT_NIL, dev->nodename, state,
+ err = xenbus_printf(XBT_NIL, dev->nodename, state,
"%d", XenbusStateClosed);
+ if (err)
+ xenbus_dev_error(info->dev, err,
+ "%s: writing %s", __func__, state);
return;
}
diff --git a/include/xen/xen.h b/include/xen/xen.h
index 9d4340c907d17d0c2ecacdd6762e36d7c9d6def5..1e1d9bd0bd3788711d8722e7ec9e1a15661d7c3b 100644
--- a/include/xen/xen.h
+++ b/include/xen/xen.h
@@ -25,12 +25,16 @@ extern bool xen_pvh;
#define xen_hvm_domain() (xen_domain_type == XEN_HVM_DOMAIN)
#define xen_pvh_domain() (xen_pvh)
+#include <linux/types.h>
+
+extern uint32_t xen_start_flags;
+
#ifdef CONFIG_XEN_DOM0
#include <xen/interface/xen.h>
#include <asm/xen/hypervisor.h>
#define xen_initial_domain() (xen_domain() && \
- xen_start_info && xen_start_info->flags & SIF_INITDOMAIN)
+ (xen_start_flags & SIF_INITDOMAIN))
#else /* !CONFIG_XEN_DOM0 */
#define xen_initial_domain() (0)
#endif /* CONFIG_XEN_DOM0 */