diff options
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/grant-table.c | 48 |
1 files changed, 29 insertions, 19 deletions
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index b91f14e83164..95ce9d02ceca 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -56,10 +56,6 @@ /* External tools reserve first few grant table entries. */ #define NR_RESERVED_ENTRIES 8 #define GNTTAB_LIST_END 0xffffffff -#define GREFS_PER_GRANT_FRAME \ -(grant_table_version == 1 ? \ -(PAGE_SIZE / sizeof(struct grant_entry_v1)) : \ -(PAGE_SIZE / sizeof(union grant_entry_v2))) static grant_ref_t **gnttab_list; static unsigned int nr_grant_frames; @@ -154,6 +150,7 @@ static struct gnttab_ops *gnttab_interface; static grant_status_t *grstatus; static int grant_table_version; +static int grefs_per_grant_frame; static struct gnttab_free_callback *gnttab_free_callback_list; @@ -767,12 +764,14 @@ static int grow_gnttab_list(unsigned int more_frames) unsigned int new_nr_grant_frames, extra_entries, i; unsigned int nr_glist_frames, new_nr_glist_frames; + BUG_ON(grefs_per_grant_frame == 0); + new_nr_grant_frames = nr_grant_frames + more_frames; - extra_entries = more_frames * GREFS_PER_GRANT_FRAME; + extra_entries = more_frames * grefs_per_grant_frame; - nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP; + nr_glist_frames = (nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP; new_nr_glist_frames = - (new_nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP; + (new_nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP; for (i = nr_glist_frames; i < new_nr_glist_frames; i++) { gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC); if (!gnttab_list[i]) @@ -780,12 +779,12 @@ static int grow_gnttab_list(unsigned int more_frames) } - for (i = GREFS_PER_GRANT_FRAME * nr_grant_frames; - i < GREFS_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++) + for (i = grefs_per_grant_frame * nr_grant_frames; + i < grefs_per_grant_frame * new_nr_grant_frames - 1; i++) gnttab_entry(i) = i + 1; gnttab_entry(i) = gnttab_free_head; - gnttab_free_head = GREFS_PER_GRANT_FRAME * nr_grant_frames; + gnttab_free_head = grefs_per_grant_frame * nr_grant_frames; gnttab_free_count += extra_entries; nr_grant_frames = new_nr_grant_frames; @@ -957,7 +956,8 @@ EXPORT_SYMBOL_GPL(gnttab_unmap_refs); static unsigned nr_status_frames(unsigned nr_grant_frames) { - return (nr_grant_frames * GREFS_PER_GRANT_FRAME + SPP - 1) / SPP; + BUG_ON(grefs_per_grant_frame == 0); + return (nr_grant_frames * grefs_per_grant_frame + SPP - 1) / SPP; } static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes) @@ -1115,6 +1115,7 @@ static void gnttab_request_version(void) rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1); if (rc == 0 && gsv.version == 2) { grant_table_version = 2; + grefs_per_grant_frame = PAGE_SIZE / sizeof(union grant_entry_v2); gnttab_interface = &gnttab_v2_ops; } else if (grant_table_version == 2) { /* @@ -1127,17 +1128,17 @@ static void gnttab_request_version(void) panic("we need grant tables version 2, but only version 1 is available"); } else { grant_table_version = 1; + grefs_per_grant_frame = PAGE_SIZE / sizeof(struct grant_entry_v1); gnttab_interface = &gnttab_v1_ops; } printk(KERN_INFO "Grant tables using version %d layout.\n", grant_table_version); } -int gnttab_resume(void) +static int gnttab_setup(void) { unsigned int max_nr_gframes; - gnttab_request_version(); max_nr_gframes = gnttab_max_grant_frames(); if (max_nr_gframes < nr_grant_frames) return -ENOSYS; @@ -1160,6 +1161,12 @@ int gnttab_resume(void) return 0; } +int gnttab_resume(void) +{ + gnttab_request_version(); + return gnttab_setup(); +} + int gnttab_suspend(void) { gnttab_interface->unmap_frames(); @@ -1171,9 +1178,10 @@ static int gnttab_expand(unsigned int req_entries) int rc; unsigned int cur, extra; + BUG_ON(grefs_per_grant_frame == 0); cur = nr_grant_frames; - extra = ((req_entries + (GREFS_PER_GRANT_FRAME-1)) / - GREFS_PER_GRANT_FRAME); + extra = ((req_entries + (grefs_per_grant_frame-1)) / + grefs_per_grant_frame); if (cur + extra > gnttab_max_grant_frames()) return -ENOSPC; @@ -1191,21 +1199,23 @@ int gnttab_init(void) unsigned int nr_init_grefs; int ret; + gnttab_request_version(); nr_grant_frames = 1; boot_max_nr_grant_frames = __max_nr_grant_frames(); /* Determine the maximum number of frames required for the * grant reference free list on the current hypervisor. */ + BUG_ON(grefs_per_grant_frame == 0); max_nr_glist_frames = (boot_max_nr_grant_frames * - GREFS_PER_GRANT_FRAME / RPP); + grefs_per_grant_frame / RPP); gnttab_list = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *), GFP_KERNEL); if (gnttab_list == NULL) return -ENOMEM; - nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP; + nr_glist_frames = (nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP; for (i = 0; i < nr_glist_frames; i++) { gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL); if (gnttab_list[i] == NULL) { @@ -1214,12 +1224,12 @@ int gnttab_init(void) } } - if (gnttab_resume() < 0) { + if (gnttab_setup() < 0) { ret = -ENODEV; goto ini_nomem; } - nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME; + nr_init_grefs = nr_grant_frames * grefs_per_grant_frame; for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++) gnttab_entry(i) = i + 1; |