diff options
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/grant-table.c | 53 | ||||
| -rw-r--r-- | drivers/xen/xenbus/xenbus_client.c | 6 |
2 files changed, 55 insertions, 4 deletions
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index eea81cf8a2a5..3a567b15600b 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -38,6 +38,7 @@ #include <linux/vmalloc.h> #include <linux/uaccess.h> #include <linux/io.h> +#include <linux/delay.h> #include <linux/hardirq.h> #include <xen/xen.h> @@ -823,6 +824,52 @@ unsigned int gnttab_max_grant_frames(void) } EXPORT_SYMBOL_GPL(gnttab_max_grant_frames); +/* Handling of paged out grant targets (GNTST_eagain) */ +#define MAX_DELAY 256 +static inline void +gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status, + const char *func) +{ + unsigned delay = 1; + + do { + BUG_ON(HYPERVISOR_grant_table_op(cmd, gop, 1)); + if (*status == GNTST_eagain) + msleep(delay++); + } while ((*status == GNTST_eagain) && (delay < MAX_DELAY)); + + if (delay >= MAX_DELAY) { + printk(KERN_ERR "%s: %s eagain grant\n", func, current->comm); + *status = GNTST_bad_page; + } +} + +void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count) +{ + struct gnttab_map_grant_ref *op; + + if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, batch, count)) + BUG(); + for (op = batch; op < batch + count; op++) + if (op->status == GNTST_eagain) + gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, op, + &op->status, __func__); +} +EXPORT_SYMBOL_GPL(gnttab_batch_map); + +void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count) +{ + struct gnttab_copy *op; + + if (HYPERVISOR_grant_table_op(GNTTABOP_copy, batch, count)) + BUG(); + for (op = batch; op < batch + count; op++) + if (op->status == GNTST_eagain) + gnttab_retry_eagain_gop(GNTTABOP_copy, op, + &op->status, __func__); +} +EXPORT_SYMBOL_GPL(gnttab_batch_copy); + int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, struct gnttab_map_grant_ref *kmap_ops, struct page **pages, unsigned int count) @@ -836,6 +883,12 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, if (ret) return ret; + /* Retry eagain maps */ + for (i = 0; i < count; i++) + if (map_ops[i].status == GNTST_eagain) + gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i, + &map_ops[i].status, __func__); + if (xen_feature(XENFEAT_auto_translated_physmap)) return ret; diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index b3e146edb51d..bcf3ba4a6ec1 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -490,8 +490,7 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev, op.host_addr = arbitrary_virt_to_machine(pte).maddr; - if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1)) - BUG(); + gnttab_batch_map(&op, 1); if (op.status != GNTST_okay) { free_vm_area(area); @@ -572,8 +571,7 @@ int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref, gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref, dev->otherend_id); - if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1)) - BUG(); + gnttab_batch_map(&op, 1); if (op.status != GNTST_okay) { xenbus_dev_fatal(dev, op.status, |