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authorLinus Torvalds <torvalds@linux-foundation.org>2020-07-03 23:58:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-07-03 23:58:12 -0700
commit35e884f89df4c48566d745dc5a97a0d058d04263 (patch)
treeade681a937b1c80511d280a4191d415e585873d4 /drivers/xen/xenbus/xenbus_client.c
parent8b082a41dae7d420db649bffe86cf5af62121f11 (diff)
parent578c1bb9056263ad3c9e09746b3d6e4daf63bdb0 (diff)
downloadlinux-stericsson-35e884f89df4c48566d745dc5a97a0d058d04263.tar.gz
Merge tag 'for-linus-5.8b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross: "One small cleanup patch for ARM and two patches for the xenbus driver fixing latent problems (large stack allocations and bad return code settings)" * tag 'for-linus-5.8b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/xenbus: let xenbus_map_ring_valloc() return errno values only xen/xenbus: avoid large structs and arrays on the stack arm/xen: remove the unused macro GRANT_TABLE_PHYSADDR
Diffstat (limited to 'drivers/xen/xenbus/xenbus_client.c')
-rw-r--r--drivers/xen/xenbus/xenbus_client.c167
1 files changed, 81 insertions, 86 deletions
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 040d2a43e8e3..4f168b46fbca 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -69,11 +69,27 @@ struct xenbus_map_node {
unsigned int nr_handles;
};
+struct map_ring_valloc {
+ struct xenbus_map_node *node;
+
+ /* Why do we need two arrays? See comment of __xenbus_map_ring */
+ union {
+ unsigned long addrs[XENBUS_MAX_RING_GRANTS];
+ pte_t *ptes[XENBUS_MAX_RING_GRANTS];
+ };
+ phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
+
+ struct gnttab_map_grant_ref map[XENBUS_MAX_RING_GRANTS];
+ struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
+
+ unsigned int idx; /* HVM only. */
+};
+
static DEFINE_SPINLOCK(xenbus_valloc_lock);
static LIST_HEAD(xenbus_valloc_pages);
struct xenbus_ring_ops {
- int (*map)(struct xenbus_device *dev,
+ int (*map)(struct xenbus_device *dev, struct map_ring_valloc *info,
grant_ref_t *gnt_refs, unsigned int nr_grefs,
void **vaddr);
int (*unmap)(struct xenbus_device *dev, void *vaddr);
@@ -440,8 +456,7 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn);
* Map @nr_grefs pages of memory into this domain from another
* domain's grant table. xenbus_map_ring_valloc allocates @nr_grefs
* pages of virtual address space, maps the pages to that address, and
- * sets *vaddr to that address. Returns 0 on success, and GNTST_*
- * (see xen/include/interface/grant_table.h) or -ENOMEM / -EINVAL on
+ * sets *vaddr to that address. Returns 0 on success, and -errno on
* error. If an error is returned, device will switch to
* XenbusStateClosing and the error message will be saved in XenStore.
*/
@@ -449,12 +464,25 @@ int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
unsigned int nr_grefs, void **vaddr)
{
int err;
+ struct map_ring_valloc *info;
+
+ *vaddr = NULL;
+
+ if (nr_grefs > XENBUS_MAX_RING_GRANTS)
+ return -EINVAL;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
- err = ring_ops->map(dev, gnt_refs, nr_grefs, vaddr);
- /* Some hypervisors are buggy and can return 1. */
- if (err > 0)
- err = GNTST_general_error;
+ info->node = kzalloc(sizeof(*info->node), GFP_KERNEL);
+ if (!info->node)
+ err = -ENOMEM;
+ else
+ err = ring_ops->map(dev, info, gnt_refs, nr_grefs, vaddr);
+ kfree(info->node);
+ kfree(info);
return err;
}
EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
@@ -466,62 +494,57 @@ static int __xenbus_map_ring(struct xenbus_device *dev,
grant_ref_t *gnt_refs,
unsigned int nr_grefs,
grant_handle_t *handles,
- phys_addr_t *addrs,
+ struct map_ring_valloc *info,
unsigned int flags,
bool *leaked)
{
- struct gnttab_map_grant_ref map[XENBUS_MAX_RING_GRANTS];
- struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
int i, j;
- int err = GNTST_okay;
if (nr_grefs > XENBUS_MAX_RING_GRANTS)
return -EINVAL;
for (i = 0; i < nr_grefs; i++) {
- memset(&map[i], 0, sizeof(map[i]));
- gnttab_set_map_op(&map[i], addrs[i], flags, gnt_refs[i],
- dev->otherend_id);
+ gnttab_set_map_op(&info->map[i], info->phys_addrs[i], flags,
+ gnt_refs[i], dev->otherend_id);
handles[i] = INVALID_GRANT_HANDLE;
}
- gnttab_batch_map(map, i);
+ gnttab_batch_map(info->map, i);
for (i = 0; i < nr_grefs; i++) {
- if (map[i].status != GNTST_okay) {
- err = map[i].status;
- xenbus_dev_fatal(dev, map[i].status,
+ if (info->map[i].status != GNTST_okay) {
+ xenbus_dev_fatal(dev, info->map[i].status,
"mapping in shared page %d from domain %d",
gnt_refs[i], dev->otherend_id);
goto fail;
} else
- handles[i] = map[i].handle;
+ handles[i] = info->map[i].handle;
}
- return GNTST_okay;
+ return 0;
fail:
for (i = j = 0; i < nr_grefs; i++) {
if (handles[i] != INVALID_GRANT_HANDLE) {
- memset(&unmap[j], 0, sizeof(unmap[j]));
- gnttab_set_unmap_op(&unmap[j], (phys_addr_t)addrs[i],
+ gnttab_set_unmap_op(&info->unmap[j],
+ info->phys_addrs[i],
GNTMAP_host_map, handles[i]);
j++;
}
}
- if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, j))
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, info->unmap, j))
BUG();
*leaked = false;
for (i = 0; i < j; i++) {
- if (unmap[i].status != GNTST_okay) {
+ if (info->unmap[i].status != GNTST_okay) {
*leaked = true;
break;
}
}
- return err;
+ return -ENOENT;
}
/**
@@ -566,21 +589,12 @@ static int xenbus_unmap_ring(struct xenbus_device *dev, grant_handle_t *handles,
return err;
}
-struct map_ring_valloc_hvm
-{
- unsigned int idx;
-
- /* Why do we need two arrays? See comment of __xenbus_map_ring */
- phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
- unsigned long addrs[XENBUS_MAX_RING_GRANTS];
-};
-
static void xenbus_map_ring_setup_grant_hvm(unsigned long gfn,
unsigned int goffset,
unsigned int len,
void *data)
{
- struct map_ring_valloc_hvm *info = data;
+ struct map_ring_valloc *info = data;
unsigned long vaddr = (unsigned long)gfn_to_virt(gfn);
info->phys_addrs[info->idx] = vaddr;
@@ -589,39 +603,28 @@ static void xenbus_map_ring_setup_grant_hvm(unsigned long gfn,
info->idx++;
}
-static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
- grant_ref_t *gnt_ref,
- unsigned int nr_grefs,
- void **vaddr)
+static int xenbus_map_ring_hvm(struct xenbus_device *dev,
+ struct map_ring_valloc *info,
+ grant_ref_t *gnt_ref,
+ unsigned int nr_grefs,
+ void **vaddr)
{
- struct xenbus_map_node *node;
+ struct xenbus_map_node *node = info->node;
int err;
void *addr;
bool leaked = false;
- struct map_ring_valloc_hvm info = {
- .idx = 0,
- };
unsigned int nr_pages = XENBUS_PAGES(nr_grefs);
- if (nr_grefs > XENBUS_MAX_RING_GRANTS)
- return -EINVAL;
-
- *vaddr = NULL;
-
- node = kzalloc(sizeof(*node), GFP_KERNEL);
- if (!node)
- return -ENOMEM;
-
err = alloc_xenballooned_pages(nr_pages, node->hvm.pages);
if (err)
goto out_err;
gnttab_foreach_grant(node->hvm.pages, nr_grefs,
xenbus_map_ring_setup_grant_hvm,
- &info);
+ info);
err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles,
- info.phys_addrs, GNTMAP_host_map, &leaked);
+ info, GNTMAP_host_map, &leaked);
node->nr_handles = nr_grefs;
if (err)
@@ -641,11 +644,13 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
spin_unlock(&xenbus_valloc_lock);
*vaddr = addr;
+ info->node = NULL;
+
return 0;
out_xenbus_unmap_ring:
if (!leaked)
- xenbus_unmap_ring(dev, node->handles, nr_grefs, info.addrs);
+ xenbus_unmap_ring(dev, node->handles, nr_grefs, info->addrs);
else
pr_alert("leaking %p size %u page(s)",
addr, nr_pages);
@@ -653,7 +658,6 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
if (!leaked)
free_xenballooned_pages(nr_pages, node->hvm.pages);
out_err:
- kfree(node);
return err;
}
@@ -676,40 +680,30 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
#ifdef CONFIG_XEN_PV
-static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
- grant_ref_t *gnt_refs,
- unsigned int nr_grefs,
- void **vaddr)
+static int xenbus_map_ring_pv(struct xenbus_device *dev,
+ struct map_ring_valloc *info,
+ grant_ref_t *gnt_refs,
+ unsigned int nr_grefs,
+ void **vaddr)
{
- struct xenbus_map_node *node;
+ struct xenbus_map_node *node = info->node;
struct vm_struct *area;
- pte_t *ptes[XENBUS_MAX_RING_GRANTS];
- phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
int err = GNTST_okay;
int i;
bool leaked;
- *vaddr = NULL;
-
- if (nr_grefs > XENBUS_MAX_RING_GRANTS)
- return -EINVAL;
-
- node = kzalloc(sizeof(*node), GFP_KERNEL);
- if (!node)
- return -ENOMEM;
-
- area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, ptes);
+ area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, info->ptes);
if (!area) {
kfree(node);
return -ENOMEM;
}
for (i = 0; i < nr_grefs; i++)
- phys_addrs[i] = arbitrary_virt_to_machine(ptes[i]).maddr;
+ info->phys_addrs[i] =
+ arbitrary_virt_to_machine(info->ptes[i]).maddr;
err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
- phys_addrs,
- GNTMAP_host_map | GNTMAP_contains_pte,
+ info, GNTMAP_host_map | GNTMAP_contains_pte,
&leaked);
if (err)
goto failed;
@@ -722,6 +716,8 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
spin_unlock(&xenbus_valloc_lock);
*vaddr = area->addr;
+ info->node = NULL;
+
return 0;
failed:
@@ -730,11 +726,10 @@ failed:
else
pr_alert("leaking VM area %p size %u page(s)", area, nr_grefs);
- kfree(node);
return err;
}
-static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
+static int xenbus_unmap_ring_pv(struct xenbus_device *dev, void *vaddr)
{
struct xenbus_map_node *node;
struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
@@ -798,12 +793,12 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
}
static const struct xenbus_ring_ops ring_ops_pv = {
- .map = xenbus_map_ring_valloc_pv,
- .unmap = xenbus_unmap_ring_vfree_pv,
+ .map = xenbus_map_ring_pv,
+ .unmap = xenbus_unmap_ring_pv,
};
#endif
-struct unmap_ring_vfree_hvm
+struct unmap_ring_hvm
{
unsigned int idx;
unsigned long addrs[XENBUS_MAX_RING_GRANTS];
@@ -814,19 +809,19 @@ static void xenbus_unmap_ring_setup_grant_hvm(unsigned long gfn,
unsigned int len,
void *data)
{
- struct unmap_ring_vfree_hvm *info = data;
+ struct unmap_ring_hvm *info = data;
info->addrs[info->idx] = (unsigned long)gfn_to_virt(gfn);
info->idx++;
}
-static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
+static int xenbus_unmap_ring_hvm(struct xenbus_device *dev, void *vaddr)
{
int rv;
struct xenbus_map_node *node;
void *addr;
- struct unmap_ring_vfree_hvm info = {
+ struct unmap_ring_hvm info = {
.idx = 0,
};
unsigned int nr_pages;
@@ -887,8 +882,8 @@ enum xenbus_state xenbus_read_driver_state(const char *path)
EXPORT_SYMBOL_GPL(xenbus_read_driver_state);
static const struct xenbus_ring_ops ring_ops_hvm = {
- .map = xenbus_map_ring_valloc_hvm,
- .unmap = xenbus_unmap_ring_vfree_hvm,
+ .map = xenbus_map_ring_hvm,
+ .unmap = xenbus_unmap_ring_hvm,
};
void __init xenbus_ring_ops_init(void)