From 49f8b459fc1de5e3712b57c8ccefae9ec45270f8 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 24 May 2022 13:46:30 +0200 Subject: xen: switch gnttab_end_foreign_access() to take a struct page pointer Instead of a virtual kernel address use a pointer of the associated struct page as second parameter of gnttab_end_foreign_access(). Most users have that pointer available already and are creating the virtual address from it, risking problems in case the memory is located in highmem. gnttab_end_foreign_access() itself won't need to get the struct page from the address again. Suggested-by: Jan Beulich Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Signed-off-by: Juergen Gross --- include/xen/grant_table.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 7d0f2f0037b8..527c9907f99c 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -101,10 +101,10 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref); * Eventually end access through the given grant reference, and once that * access has been ended, free the given page too. Access will be ended * immediately iff the grant entry is not in use, otherwise it will happen - * some time later. page may be 0, in which case no freeing will occur. + * some time later. page may be NULL, in which case no freeing will occur. * Note that the granted page might still be accessed (read or write) by the * other side after gnttab_end_foreign_access() returns, so even if page was - * specified as 0 it is not allowed to just reuse the page for other + * specified as NULL it is not allowed to just reuse the page for other * purposes immediately. gnttab_end_foreign_access() will take an additional * reference to the granted page in this case, which is dropped only after * the grant is no longer in use. @@ -112,7 +112,7 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref); * gnttab_end_foreign_access() are done via alloc_pages_exact() (and freeing * via free_pages_exact()) in order to avoid high order pages. */ -void gnttab_end_foreign_access(grant_ref_t ref, unsigned long page); +void gnttab_end_foreign_access(grant_ref_t ref, struct page *page); /* * End access through the given grant reference, iff the grant entry is -- cgit v1.2.3 From 41925b105e345ebc84cedb64f59d20cb14a62613 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 30 May 2022 10:26:34 +0200 Subject: xen: replace xen_remap() with memremap() xen_remap() is used to establish mappings for frames not under direct control of the kernel: for Xenstore and console ring pages, and for grant pages of non-PV guests. Today xen_remap() is defined to use ioremap() on x86 (doing uncached mappings), and ioremap_cache() on Arm (doing cached mappings). Uncached mappings for those use cases are bad for performance, so they should be avoided if possible. As all use cases of xen_remap() don't require uncached mappings (the mapped area is always physical RAM), a mapping using the standard WB cache mode is fine. As sparse is flagging some of the xen_remap() use cases to be not appropriate for iomem(), as the result is not annotated with the __iomem modifier, eliminate xen_remap() completely and replace all use cases with memremap() specifying the MEMREMAP_WB caching mode. xen_unmap() can be replaced with memunmap(). Reported-by: kernel test robot Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky Acked-by: Stefano Stabellini Link: https://lore.kernel.org/r/20220530082634.6339-1-jgross@suse.com Signed-off-by: Juergen Gross --- arch/x86/include/asm/xen/page.h | 3 --- drivers/tty/hvc/hvc_xen.c | 2 +- drivers/xen/grant-table.c | 6 +++--- drivers/xen/xenbus/xenbus_probe.c | 8 ++++---- include/xen/arm/page.h | 3 --- 5 files changed, 8 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index e989bc2269f5..777e6b21efe9 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -347,9 +347,6 @@ unsigned long arbitrary_virt_to_mfn(void *vaddr); void make_lowmem_page_readonly(void *vaddr); void make_lowmem_page_readwrite(void *vaddr); -#define xen_remap(cookie, size) ioremap((cookie), (size)) -#define xen_unmap(cookie) iounmap((cookie)) - static inline bool xen_arch_need_swiotlb(struct device *dev, phys_addr_t phys, dma_addr_t dev_addr) diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index ebaf7500f48f..7c23112dc923 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -253,7 +253,7 @@ static int xen_hvm_console_init(void) if (r < 0 || v == 0) goto err; gfn = v; - info->intf = xen_remap(gfn << XEN_PAGE_SHIFT, XEN_PAGE_SIZE); + info->intf = memremap(gfn << XEN_PAGE_SHIFT, XEN_PAGE_SIZE, MEMREMAP_WB); if (info->intf == NULL) goto err; info->vtermno = HVC_COOKIE; diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 1b9b28bc3228..7a18292540bc 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -632,7 +632,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr) if (xen_auto_xlat_grant_frames.count) return -EINVAL; - vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes); + vaddr = memremap(addr, XEN_PAGE_SIZE * max_nr_gframes, MEMREMAP_WB); if (vaddr == NULL) { pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n", &addr); @@ -640,7 +640,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr) } pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL); if (!pfn) { - xen_unmap(vaddr); + memunmap(vaddr); return -ENOMEM; } for (i = 0; i < max_nr_gframes; i++) @@ -659,7 +659,7 @@ void gnttab_free_auto_xlat_frames(void) if (!xen_auto_xlat_grant_frames.count) return; kfree(xen_auto_xlat_grant_frames.pfn); - xen_unmap(xen_auto_xlat_grant_frames.vaddr); + memunmap(xen_auto_xlat_grant_frames.vaddr); xen_auto_xlat_grant_frames.pfn = NULL; xen_auto_xlat_grant_frames.count = 0; diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index d367f2bd2b93..58b732dcbfb8 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -752,8 +752,8 @@ static void xenbus_probe(void) xenstored_ready = 1; if (!xen_store_interface) { - xen_store_interface = xen_remap(xen_store_gfn << XEN_PAGE_SHIFT, - XEN_PAGE_SIZE); + xen_store_interface = memremap(xen_store_gfn << XEN_PAGE_SHIFT, + XEN_PAGE_SIZE, MEMREMAP_WB); /* * Now it is safe to free the IRQ used for xenstore late * initialization. No need to unbind: it is about to be @@ -1009,8 +1009,8 @@ static int __init xenbus_init(void) #endif xen_store_gfn = (unsigned long)v; xen_store_interface = - xen_remap(xen_store_gfn << XEN_PAGE_SHIFT, - XEN_PAGE_SIZE); + memremap(xen_store_gfn << XEN_PAGE_SHIFT, + XEN_PAGE_SIZE, MEMREMAP_WB); if (xen_store_interface->connection != XENSTORE_CONNECTED) wait = true; } diff --git a/include/xen/arm/page.h b/include/xen/arm/page.h index ac1b65470563..f831cfeca000 100644 --- a/include/xen/arm/page.h +++ b/include/xen/arm/page.h @@ -109,9 +109,6 @@ static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) return __set_phys_to_machine(pfn, mfn); } -#define xen_remap(cookie, size) ioremap_cache((cookie), (size)) -#define xen_unmap(cookie) iounmap((cookie)) - bool xen_arch_need_swiotlb(struct device *dev, phys_addr_t phys, dma_addr_t dev_addr); -- cgit v1.2.3