From 853d0289340026b30f93fd0e768340221d4e605c Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Mon, 5 Jan 2015 14:13:41 +0000 Subject: [PATCH] xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs() When unmapping grants, instead of converting the kernel map ops to unmap ops on the fly, pre-populate the set of unmap ops. This allows the grant unmap for the kernel mappings to be trivially batched in the future. Signed-off-by: David Vrabel Reviewed-by: Stefano Stabellini --- arch/arm/include/asm/xen/page.h | 2 +- arch/arm/xen/p2m.c | 2 +- arch/x86/include/asm/xen/page.h | 2 +- arch/x86/xen/p2m.c | 21 ++++++++++----------- drivers/xen/gntdev.c | 20 ++++++++++++++------ drivers/xen/grant-table.c | 4 ++-- include/xen/grant_table.h | 2 +- 7 files changed, 30 insertions(+), 23 deletions(-) diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h index 68c739b3fdf4..2f7e6ff67d51 100644 --- a/arch/arm/include/asm/xen/page.h +++ b/arch/arm/include/asm/xen/page.h @@ -92,7 +92,7 @@ extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, struct page **pages, unsigned int count); extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count); bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn); diff --git a/arch/arm/xen/p2m.c b/arch/arm/xen/p2m.c index 054857776254..cb7a14c5cd69 100644 --- a/arch/arm/xen/p2m.c +++ b/arch/arm/xen/p2m.c @@ -102,7 +102,7 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping); int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count) { int i; diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 5eea09915a15..e9f52fe2d56a 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -55,7 +55,7 @@ extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, struct gnttab_map_grant_ref *kmap_ops, struct page **pages, unsigned int count); extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count); extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn); diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 70fb5075c901..df40b2888eae 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -816,7 +816,7 @@ static struct page *m2p_find_override(unsigned long mfn) } static int m2p_remove_override(struct page *page, - struct gnttab_map_grant_ref *kmap_op, + struct gnttab_unmap_grant_ref *kunmap_op, unsigned long mfn) { unsigned long flags; @@ -840,7 +840,7 @@ static int m2p_remove_override(struct page *page, list_del(&page->lru); spin_unlock_irqrestore(&m2p_override_lock, flags); - if (kmap_op != NULL) { + if (kunmap_op != NULL) { if (!PageHighMem(page)) { struct multicall_space mcs; struct gnttab_unmap_and_replace *unmap_op; @@ -855,13 +855,13 @@ static int m2p_remove_override(struct page *page, * issued. In this case handle is going to -1 because * it hasn't been modified yet. */ - if (kmap_op->handle == -1) + if (kunmap_op->handle == -1) xen_mc_flush(); /* * Now if kmap_op->handle is negative it means that the * hypercall actually returned an error. */ - if (kmap_op->handle == GNTST_general_error) { + if (kunmap_op->handle == GNTST_general_error) { pr_warn("m2p_remove_override: pfn %lx mfn %lx, failed to modify kernel mappings", pfn, mfn); put_balloon_scratch_page(); @@ -873,9 +873,9 @@ static int m2p_remove_override(struct page *page, mcs = __xen_mc_entry( sizeof(struct gnttab_unmap_and_replace)); unmap_op = mcs.args; - unmap_op->host_addr = kmap_op->host_addr; + unmap_op->host_addr = kunmap_op->host_addr; unmap_op->new_addr = scratch_page_address; - unmap_op->handle = kmap_op->handle; + unmap_op->handle = kunmap_op->handle; MULTI_grant_table_op(mcs.mc, GNTTABOP_unmap_and_replace, unmap_op, 1); @@ -887,7 +887,6 @@ static int m2p_remove_override(struct page *page, xen_mc_issue(PARAVIRT_LAZY_MMU); - kmap_op->host_addr = 0; put_balloon_scratch_page(); } } @@ -912,7 +911,7 @@ static int m2p_remove_override(struct page *page, } int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count) { int i, ret = 0; @@ -921,7 +920,7 @@ int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, if (xen_feature(XENFEAT_auto_translated_physmap)) return 0; - if (kmap_ops && + if (kunmap_ops && !in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) { arch_enter_lazy_mmu_mode(); @@ -942,8 +941,8 @@ int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, ClearPagePrivate(pages[i]); set_phys_to_machine(pfn, pages[i]->index); - if (kmap_ops) - ret = m2p_remove_override(pages[i], &kmap_ops[i], mfn); + if (kunmap_ops) + ret = m2p_remove_override(pages[i], &kunmap_ops[i], mfn); if (ret) goto out; } diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 073b4a19a8b0..6444172f2842 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -91,6 +91,7 @@ struct grant_map { struct gnttab_map_grant_ref *map_ops; struct gnttab_unmap_grant_ref *unmap_ops; struct gnttab_map_grant_ref *kmap_ops; + struct gnttab_unmap_grant_ref *kunmap_ops; struct page **pages; }; @@ -124,6 +125,7 @@ static void gntdev_free_map(struct grant_map *map) kfree(map->map_ops); kfree(map->unmap_ops); kfree(map->kmap_ops); + kfree(map->kunmap_ops); kfree(map); } @@ -140,11 +142,13 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count) add->map_ops = kcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL); add->unmap_ops = kcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL); add->kmap_ops = kcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL); + add->kunmap_ops = kcalloc(count, sizeof(add->kunmap_ops[0]), GFP_KERNEL); add->pages = kcalloc(count, sizeof(add->pages[0]), GFP_KERNEL); if (NULL == add->grants || NULL == add->map_ops || NULL == add->unmap_ops || NULL == add->kmap_ops || + NULL == add->kunmap_ops || NULL == add->pages) goto err; @@ -155,6 +159,7 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count) add->map_ops[i].handle = -1; add->unmap_ops[i].handle = -1; add->kmap_ops[i].handle = -1; + add->kunmap_ops[i].handle = -1; } add->index = 0; @@ -280,6 +285,8 @@ static int map_grant_pages(struct grant_map *map) map->flags | GNTMAP_host_map, map->grants[i].ref, map->grants[i].domid); + gnttab_set_unmap_op(&map->kunmap_ops[i], address, + map->flags | GNTMAP_host_map, -1); } } @@ -290,13 +297,14 @@ static int map_grant_pages(struct grant_map *map) return err; for (i = 0; i < map->count; i++) { - if (map->map_ops[i].status) + if (map->map_ops[i].status) { err = -EINVAL; - else { - BUG_ON(map->map_ops[i].handle == -1); - map->unmap_ops[i].handle = map->map_ops[i].handle; - pr_debug("map handle=%d\n", map->map_ops[i].handle); + continue; } + + map->unmap_ops[i].handle = map->map_ops[i].handle; + if (use_ptemod) + map->kunmap_ops[i].handle = map->kmap_ops[i].handle; } return err; } @@ -316,7 +324,7 @@ static int __unmap_grant_pages(struct grant_map *map, int offset, int pages) } err = gnttab_unmap_refs(map->unmap_ops + offset, - use_ptemod ? map->kmap_ops + offset : NULL, map->pages + offset, + use_ptemod ? map->kunmap_ops + offset : NULL, map->pages + offset, pages); if (err) return err; diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 7786291ba229..999d7abdbcec 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -738,7 +738,7 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, EXPORT_SYMBOL_GPL(gnttab_map_refs); int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count) { int ret; @@ -747,7 +747,7 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, if (ret) return ret; - return clear_foreign_p2m_mapping(unmap_ops, kmap_ops, pages, count); + return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count); } EXPORT_SYMBOL_GPL(gnttab_unmap_refs); diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 3387465b9caa..7235d8f35459 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -167,7 +167,7 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, struct gnttab_map_grant_ref *kmap_ops, struct page **pages, unsigned int count); int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, - struct gnttab_map_grant_ref *kunmap_ops, + struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count); /* Perform a batch of grant map/copy operations. Retry every batch slot -- 2.20.1