| Message ID | 20220530082634.6339-1-jgross@suse.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | xen: replace xen_remap() with memremap() | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 7 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | success | Successfully ran 24 jobs. |
On 5/30/22 4:26 AM, Juergen Gross wrote: > 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 <lkp@intel.com> > Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
On Mon, 30 May 2022, Juergen Gross wrote: > 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 <lkp@intel.com> > Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Stefano Stabellini <sstabellini@kernel.org> > --- > 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(-) > > diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h > index 1fc67df50014..fa9ec20783fa 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 1a1aec0a88a1..2f4f0ed5d8f8 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 7e199c6656b9..e5c84ff28c8b 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); > -- > 2.35.3 >
diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 1fc67df50014..fa9ec20783fa 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 1a1aec0a88a1..2f4f0ed5d8f8 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 7e199c6656b9..e5c84ff28c8b 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);
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 <lkp@intel.com> Signed-off-by: Juergen Gross <jgross@suse.com> --- 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(-)