Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754866Ab3ESX1L (ORCPT ); Sun, 19 May 2013 19:27:11 -0400 Received: from ozlabs.org ([203.10.76.45]:53754 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754640Ab3ESX1K (ORCPT ); Sun, 19 May 2013 19:27:10 -0400 From: Rusty Russell To: Randy Dunlap Cc: Joe Perches , Asias He , "Michael S. Tsirkin" , Nicholas Bellinger , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, George Zhang , Dmitry Torokhov Subject: Re: [PATCH] vhost-scsi: Depend on NET for memcpy_fromiovec In-Reply-To: <5195B539.7020705@infradead.org> References: <20130515095558.918f2b29ba318a477eb5dde2@canb.auug.org.au> <1368579583-13097-1-git-send-email-asias@redhat.com> <8761yk254u.fsf@rustcorp.com.au> <20130516020848.GB23441@hj.localdomain> <87d2sra97h.fsf@rustcorp.com.au> <1368676505.2194.47.camel@joe-AO722> <878v3ea3v4.fsf@rustcorp.com.au> <5195B539.7020705@infradead.org> User-Agent: Notmuch/0.15.2+81~gd2c8818 (http://notmuchmail.org) Emacs/23.4.1 (i686-pc-linux-gnu) Date: Fri, 17 May 2013 16:25:49 +0930 Message-ID: <87ppwq858q.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9849 Lines: 297 Randy Dunlap writes: > On 05/16/13 16:42, Rusty Russell wrote: >> Joe Perches writes: >>> On Thu, 2013-05-16 at 13:04 +0930, Rusty Russell wrote: >>>> Asias He writes: >>>>> On Wed, May 15, 2013 at 02:47:53PM +0930, Rusty Russell wrote: >>> [] >>>>> Other users are using memcpy_fromiovec and friends outside net. It seems >>>>> a good idea to put it in a util library. e.g. crypto/algif_skcipher.c >>>>> which also depends on NET for it. >>> >>> [] >>>> Subject: Hoist memcpy_fromiovec into lib/ >>> >>> You'll need the "friends" memcpy_toiovec too. >>> >>> $ git grep -E \bmemcpy\w+iovec\w*" >>> crypto/algif_hash.c: err = memcpy_toiovec(msg->msg_iov, ctx->result, len); >>> crypto/algif_skcipher.c: err = memcpy_fromiovec(page_address(sg_page(sg)) + >>> crypto/algif_skcipher.c: err = memcpy_fromiovec(page_address(sg_page(sg + i)), >>> drivers/dma/iovlock.c:#include /* for memcpy_toiovec */ >>> drivers/dma/iovlock.c: return memcpy_toiovec(iov, kdata, len); >>> drivers/dma/iovlock.c: err = memcpy_toiovec(iov, vaddr + offset, len); >>> drivers/isdn/mISDN/socket.c: if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { >>> drivers/misc/vmw_vmci/vmci_queue_pair.c: err = memcpy_fromiovec((u8 *)va + page_o >>> drivers/misc/vmw_vmci/vmci_queue_pair.c: err = memcpy_toiovec(iov, (u8 *)va + pag >> >> Fascinating. These all indirectly depend on NET, so there's no problem >> at the moment. But it is a bit weird... >> >> crypto/algif_hash.c: depends on CRYPTO_USER_API_HASH -> NET >> crypto/algif_skcipher.c: depends on CRYPTO_USER_API_SKCIPHER -> NET >> drivers/dma/iovlock.c: depends on NET_DMA -> NET >> drivers/isdn/mISDN/socket.c: depends on MISDN -> ISDN -> NET >> drivers/misc/vmw_vmci/vmci_queue_pair.c: depends on VMCI -> NET >> >> Patch welcome. >> >> Meanwhile, to avoid more bikeshedding I've put the patch I posted with >> all acks in my fixes branch. One cycle through linux-next, then >> straight to Linus. >> > > I agree with whoever suggested that more be moved into /lib. > E.g., drivers/misc/vmw_vmci/Kconfig uses "depends on NET" because the > code there uses both memcpy_toiovec() and memcpy_fromiovec(). > See commit ID 6d4f0139d642c45411a47879325891ce2a7c164a. (CC's trimmed). You Acked that commit :( At a glance, the only way to drive the vmw_vmci device is through net/vmw_vsock/vmci_transport.c, so without NET it's useless? But let's keep it neat anyway. This was compiletested with CONFIG_VMCI, CONFIG_DMA_ENGINE and !CONFIG_NET. Thanks, Rusty. From: Rusty Russell Subject: [PATCH] Hoist memcpy_fromiovec/memcpy_toiovec into lib/ ERROR: "memcpy_fromiovec" [drivers/vhost/vhost_scsi.ko] undefined! That function is only present with CONFIG_NET. Turns out that crypto/algif_skcipher.c also uses that outside net, but it actually needs sockets anyway. In addition, commit 6d4f0139d642c45411a47879325891ce2a7c164a added CONFIG_NET dependency to CONFIG_VMCI for memcpy_toiovec, so hoist that function and revert that commit too. socket.h already include uio.h, so no callers *need* updating, though I update the obvious ones. Reported-by: Randy Dunlap Acked-by: David S. Miller Acked-by: Michael S. Tsirkin Signed-off-by: Rusty Russell diff --git a/drivers/dma/iovlock.c b/drivers/dma/iovlock.c index bb48a57..6943deb66 100644 --- a/drivers/dma/iovlock.c +++ b/drivers/dma/iovlock.c @@ -28,7 +28,7 @@ #include #include #include -#include /* for memcpy_toiovec */ +#include /* for memcpy_toiovec */ #include #include diff --git a/drivers/misc/vmw_vmci/Kconfig b/drivers/misc/vmw_vmci/Kconfig index ea98f7e..39c2eca 100644 --- a/drivers/misc/vmw_vmci/Kconfig +++ b/drivers/misc/vmw_vmci/Kconfig @@ -4,7 +4,7 @@ config VMWARE_VMCI tristate "VMware VMCI Driver" - depends on X86 && PCI && NET + depends on X86 && PCI help This is VMware's Virtual Machine Communication Interface. It enables high-speed communication between host and guest in a virtual diff --git a/drivers/misc/vmw_vmci/vmci_queue_pair.c b/drivers/misc/vmw_vmci/vmci_queue_pair.c index d94245d..8ff2e5e 100644 --- a/drivers/misc/vmw_vmci/vmci_queue_pair.c +++ b/drivers/misc/vmw_vmci/vmci_queue_pair.c @@ -23,7 +23,7 @@ #include #include #include -#include +#include #include #include diff --git a/include/linux/socket.h b/include/linux/socket.h index 428c37a..33bf2df 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -305,7 +305,6 @@ struct ucred { extern void cred_to_ucred(struct pid *pid, const struct cred *cred, struct ucred *ucred); -extern int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); extern int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, int offset, int len); extern int csum_partial_copy_fromiovecend(unsigned char *kdata, @@ -314,7 +313,6 @@ extern int csum_partial_copy_fromiovecend(unsigned char *kdata, unsigned int len, __wsum *csump); extern int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr_storage *address, int mode); -extern int memcpy_toiovec(struct iovec *v, unsigned char *kdata, int len); extern int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata, int offset, int len); extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr); diff --git a/include/linux/uio.h b/include/linux/uio.h index 629aaf5..c55ce24 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -35,4 +35,7 @@ static inline size_t iov_length(const struct iovec *iov, unsigned long nr_segs) } unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to); + +int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); +int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len); #endif diff --git a/lib/Makefile b/lib/Makefile index e9c52e1..2377211 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -9,7 +9,7 @@ endif lib-y := ctype.o string.o vsprintf.o cmdline.o \ rbtree.o radix-tree.o dump_stack.o timerqueue.o\ - idr.o int_sqrt.o extable.o \ + idr.o int_sqrt.o extable.o iovec.o \ sha1.o md5.o irq_regs.o reciprocal_div.o argv_split.o \ proportions.o flex_proportions.o prio_heap.o ratelimit.o show_mem.o \ is_single_threaded.o plist.o decompress.o kobject_uevent.o \ diff --git a/lib/iovec.c b/lib/iovec.c new file mode 100644 index 0000000..454baa8 --- /dev/null +++ b/lib/iovec.c @@ -0,0 +1,53 @@ +#include +#include +#include + +/* + * Copy iovec to kernel. Returns -EFAULT on error. + * + * Note: this modifies the original iovec. + */ + +int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) +{ + while (len > 0) { + if (iov->iov_len) { + int copy = min_t(unsigned int, len, iov->iov_len); + if (copy_from_user(kdata, iov->iov_base, copy)) + return -EFAULT; + len -= copy; + kdata += copy; + iov->iov_base += copy; + iov->iov_len -= copy; + } + iov++; + } + + return 0; +} +EXPORT_SYMBOL(memcpy_fromiovec); + +/* + * Copy kernel to iovec. Returns -EFAULT on error. + * + * Note: this modifies the original iovec. + */ + +int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len) +{ + while (len > 0) { + if (iov->iov_len) { + int copy = min_t(unsigned int, iov->iov_len, len); + if (copy_to_user(iov->iov_base, kdata, copy)) + return -EFAULT; + kdata += copy; + len -= copy; + iov->iov_len -= copy; + iov->iov_base += copy; + } + iov++; + } + + return 0; +} +EXPORT_SYMBOL(memcpy_toiovec); diff --git a/net/core/iovec.c b/net/core/iovec.c index 7e7aeb0..de178e4 100644 --- a/net/core/iovec.c +++ b/net/core/iovec.c @@ -75,31 +75,6 @@ int verify_iovec(struct msghdr *m, struct iovec *iov, struct sockaddr_storage *a /* * Copy kernel to iovec. Returns -EFAULT on error. - * - * Note: this modifies the original iovec. - */ - -int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len) -{ - while (len > 0) { - if (iov->iov_len) { - int copy = min_t(unsigned int, iov->iov_len, len); - if (copy_to_user(iov->iov_base, kdata, copy)) - return -EFAULT; - kdata += copy; - len -= copy; - iov->iov_len -= copy; - iov->iov_base += copy; - } - iov++; - } - - return 0; -} -EXPORT_SYMBOL(memcpy_toiovec); - -/* - * Copy kernel to iovec. Returns -EFAULT on error. */ int memcpy_toiovecend(const struct iovec *iov, unsigned char *kdata, @@ -125,31 +100,6 @@ int memcpy_toiovecend(const struct iovec *iov, unsigned char *kdata, EXPORT_SYMBOL(memcpy_toiovecend); /* - * Copy iovec to kernel. Returns -EFAULT on error. - * - * Note: this modifies the original iovec. - */ - -int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) -{ - while (len > 0) { - if (iov->iov_len) { - int copy = min_t(unsigned int, len, iov->iov_len); - if (copy_from_user(kdata, iov->iov_base, copy)) - return -EFAULT; - len -= copy; - kdata += copy; - iov->iov_base += copy; - iov->iov_len -= copy; - } - iov++; - } - - return 0; -} -EXPORT_SYMBOL(memcpy_fromiovec); - -/* * Copy iovec from kernel. Returns -EFAULT on error. */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/