Return-Path: linux-nfs-owner@vger.kernel.org Received: from smtp-outbound-1.vmware.com ([208.91.2.12]:58132 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754395Ab2D2VDm (ORCPT ); Sun, 29 Apr 2012 17:03:42 -0400 From: "Alexandre Depoutovitch" To: , References: <9c0b78d1.00001bd8.00000533@aldep-VC.vmware.com> In-Reply-To: <9c0b78d1.00001bd8.00000533@aldep-VC.vmware.com> Subject: [PATCH RFC v2] Performing direct I/O on sector-aligned requests Date: Sun, 29 Apr 2012 14:03:41 -0700 (PDT) Message-ID: <1508773761.4854678.1335731939770.JavaMail.root@zimbra-prod-mbox-3.vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: NFS daemons always perform buffered IO on files. As a result, write requests that are not aligned on a file system block boundary take about 15 times more time to complete compared to the same writes that are file system block aligned. This patch fixes the problem by analyzing alignment of the IO request that comes to NFS daemon and using Direct I/O mechanism when all of the following are true: 1. Request is not aligned on a file system block boundary 2. Request is aligned on an underlying block device's sector boundary. 3. Request size is a multiple of the sector size. In all other cases, buffered IO is performed as has been done before. A new flag is exposed to users through /proc/fs/nfsd/direct_io node. The default value of 1 results in the above behavior. Writing 0 to the node turns off the direct I/O completely, and forces NFS daemon to always use buffered IO (as it has done before). Writing 2 to the node tells NFS daemon to use direct I/O whenever possible, even if requests are aligned at file system block boundary. In order to test the patch, the following have been done: I've deployed 2 Linux machines with 3.0 kernel and my modifications. One acted as an NFS server, the other acted as an NFS client. NFS volume was mounted in sync mode. Number of NFS daemons was increased to 64 in order to have higher chances of catching concurrency issues. Volume was formatted using ext4 file system. Volume was located on a hardware RAID10 array with 8 10K 450GB SAS drives. Raid adapter was HP P410i. 1. During first set of experiments, the client machine created a 200 GB file by writing to it. Then it performed the following access patterns: Read, random, (4K) Write, random, (4K) Read, sequential (4K) Write, sequential (4K) Read, sequential (4K, first access at 512 offset) Write, sequential (4K, first access at 512 offset) Read, sequential (32K) Write, sequential (32K) Read, sequential (32K, first access at 512 offset) Write, sequential (32K, first access at 512 offset) Read, sequential (256K) Write, sequential (256K) All accesses where done with keeping 64 outstanding IO requests on a client. I compared performance of the above patterns on vanilla Linux and Linux with my changes. All numbers (IOPS, latency) where the same for all cases except for random writes, where IOPS increase was 14 times. In addition, I have done several correctness tests. 2. Allocated three 200GB files using (a) explicit writes to a file, (b) fallocate() system call, (c) seeking to the end of the file and writing one sector there. Then, did random and sequential writes to files. After that, I verified that files were indeed modified and contained the latest data. Test for each file ran for 2 hours. 3. Allocated 200GB file and started sequential reads to trigger read-ahead mechanism. Every 100 read operations, one file system unaligned write immediately after the current read position was requested in order to trigger a direct write. After that, read continued. All writes contained a predefined value, so that read can check for it. I have done this, in order to be sure that direct write correctly invalidates already in-memory cache. Current implementation performs synchronous direct I/O and may trigger higher latencies when NFS volume is mounted in asynchronous mode. In order to avoid it, as per Trond Myklebust's suggestion, iov_iter interface with asynchronous reads and writes can be used. This is why currently, Direct I/O can be enabled or disabled at boot or run-time without NFS server restart through the /proc/fs/nfsd/direct_io node. -------------------------------------------------------------------------- diff -uNr linux-orig/fs/direct-io.c linux-3.0.7-0.7.2.8796.vmw/fs/direct-io.c --- linux-orig/fs/direct-io.c 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/direct-io.c 2012-04-25 16:34:30.000000000 -0400 @@ -152,11 +152,30 @@ int nr_pages; nr_pages = min(dio->total_pages - dio->curr_page, DIO_PAGES); - ret = get_user_pages_fast( - dio->curr_user_address, /* Where from? */ - nr_pages, /* How many pages? */ - dio->rw == READ, /* Write to memory? */ - &dio->pages[0]); /* Put results here */ + + if (current->mm) { + ret = get_user_pages_fast( + dio->curr_user_address, /* Where from? */ + nr_pages, /* How many pages? */ + dio->rw == READ, /* Write to memory? */ + &dio->pages[0]); /* Put results here */ + } else { + /* For kernel threads mm is NULL, so all we need is to increment + page's reference count and add page to dio->pages array */ + int i; + struct page* page; + unsigned long start_pfn = virt_to_phys((void *)dio->curr_user_address) + >> PAGE_SHIFT; + /* For kernel threads buffer must be in kernel memory */ + BUG_ON(dio->curr_user_address < TASK_SIZE_MAX); + + for (i = 0; i < nr_pages; i++) { + page = pfn_to_page(start_pfn + i); + page_cache_get(page); + dio->pages[i] = page; + } + /* No need to lock pages: this is kernel thread and the pages are in + kernel as well */ + ret = nr_pages; + } if (ret < 0 && dio->blocks_available && (dio->rw & WRITE)) { struct page *page = ZERO_PAGE(0); @@ -972,7 +991,11 @@ break; } - /* Drop the ref which was taken in get_user_pages() */ + /* + * Drop the ref which was taken in dio_refill_pages + * directly (for direct I/O) or by calling get_user_pages + * (for buffered IO) + */ page_cache_release(page); block_in_page = 0; } diff -uNr linux-orig/fs/nfsd/lockd.c linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/lockd.c --- linux-orig/fs/nfsd/lockd.c 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/lockd.c 2012-03-28 15:40:29.000000000 -0400 @@ -36,7 +36,7 @@ fh.fh_export = NULL; exp_readlock(); - nfserr = nfsd_open(rqstp, &fh, S_IFREG, NFSD_MAY_LOCK, filp); + nfserr = nfsd_open(rqstp, &fh, S_IFREG, NFSD_MAY_LOCK, filp, 0, 0); fh_put(&fh); exp_readunlock(); /* We return nlm error codes as nlm doesn't know diff -uNr linux-orig/fs/nfsd/nfs4state.c linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfs4state.c --- linux-orig/fs/nfsd/nfs4state.c 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfs4state.c 2012-03-28 15:40:29.000000000 -0400 @@ -2557,7 +2557,7 @@ if (!fp->fi_fds[oflag]) { status = nfsd_open(rqstp, cur_fh, S_IFREG, access, - &fp->fi_fds[oflag]); + &fp->fi_fds[oflag], 0, 0); if (status) return status; } @@ -3951,7 +3951,7 @@ struct file *file; int err; - err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file); + err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file, 0, 0); if (err) return err; err = vfs_test_lock(file, lock); diff -uNr linux-orig/fs/nfsd/nfsctl.c linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfsctl.c --- linux-orig/fs/nfsd/nfsctl.c 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfsctl.c 2012-03-28 15:40:29.000000000 -0400 @@ -46,6 +46,7 @@ NFSD_TempPorts, NFSD_MaxBlkSize, NFSD_SupportedEnctypes, + NFSD_DirectIO, /* * The below MUST come last. Otherwise we leave a hole in nfsd_files[] * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops @@ -78,6 +79,7 @@ static ssize_t write_ports(struct file *file, char *buf, size_t size); static ssize_t write_temp_ports(struct file *file, char *buf, size_t size); static ssize_t write_maxblksize(struct file *file, char *buf, size_t size); +static ssize_t write_directio(struct file *file, char *buf, size_t size); #ifdef CONFIG_NFSD_V4 static ssize_t write_leasetime(struct file *file, char *buf, size_t size); static ssize_t write_gracetime(struct file *file, char *buf, size_t size); @@ -103,6 +105,7 @@ [NFSD_Ports] = write_ports, [NFSD_TempPorts] = write_temp_ports, [NFSD_MaxBlkSize] = write_maxblksize, + [NFSD_DirectIO] = write_directio, #ifdef CONFIG_NFSD_V4 [NFSD_Leasetime] = write_leasetime, [NFSD_Gracetime] = write_gracetime, @@ -1348,6 +1351,58 @@ nfsd_max_blksize); } +int nfsd_directio_mode = DIO_NEVER; + +/** + * nfsd_directio_mode - sets conditions when direct IO is activated + * + * Input: + * buf: ignored + * size: zero + * + * OR + * + * Input: + * buf: C string containing an unsigned + * integer value representing the new + * NFS direct IO mode + * size: non-zero length of C string in @buf + * Output: + * On success: passed-in buffer filled with '\n'-terminated C string + * containing numeric value of the current direct IO mode + * return code is the size in bytes of the string + * + * Possible modes are: + * DIO_NEVER (0) - never use direct I/O + * DIO_FS_UNALIGNED (1) - use direct I/O only for requests that FS unaligned + * and block device aligned + * DIO_SECTOR_ALIGNED (3) - use direct I/O for all block device aligned IO + * On error: return code is zero or a negative errno value + */ +static ssize_t write_directio(struct file *file, char *buf, size_t size) +{ + char *mesg = buf; + if (size > 0) { + int mode; + int rv = get_int(&mesg, &mode); + if (rv) + return rv; + if (mode < DIO_NEVER || mode > DIO_BDEV_ALIGNED) + return -EINVAL; + /* + There is no need for synchronization here. No harm will happen + even if mode was changed between opening a file and choosing whether + to choose direct or buffered path. When we choosing a path we make sure + that the file has been opened in the compatible mode + */ + nfsd_directio_mode = mode; + printk(KERN_WARNING"NFSD direct I/O mode changed to %d.", + nfsd_directio_mode); + } + + return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n", nfsd_directio_mode); +} + #ifdef CONFIG_NFSD_V4 static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size, time_t *time) { @@ -1525,6 +1580,7 @@ [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO}, [NFSD_TempPorts] = {"tempportlist", &transaction_ops, S_IWUSR|S_IRUGO}, [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO}, + [NFSD_DirectIO] = {"direct_io", &transaction_ops, S_IWUSR|S_IRUGO}, #if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE) [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO}, #endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */ diff -uNr linux-orig/fs/nfsd/nfsd.h linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfsd.h --- linux-orig/fs/nfsd/nfsd.h 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/nfsd.h 2012-04-17 11:45:55.000000000 -0400 @@ -68,6 +68,14 @@ extern int nfsd_max_blksize; +enum { + DIO_NEVER = 0,// Never use Direct I/O. The first value + DIO_FS_UNALIGNED = 1, // Use Direct I/O when request is FS unaligned + DIO_BDEV_ALIGNED =2, // Always use Direct I/O when possible. The last value +}; + +extern int nfsd_directio_mode; + static inline int nfsd_v4client(struct svc_rqst *rq) { return rq->rq_prog == NFS_PROGRAM && rq->rq_vers == 4; diff -uNr linux-orig/fs/nfsd/vfs.c linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/vfs.c --- linux-orig/fs/nfsd/vfs.c 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/vfs.c 2012-04-25 14:21:38.000000000 -0400 @@ -28,6 +28,7 @@ #include #include #include +#include #ifdef CONFIG_NFSD_V3 #include "xdr3.h" @@ -718,6 +719,255 @@ return break_lease(inode, mode | O_NONBLOCK); } +/* + Copies data between two iovec arrays. Individual array elements might have + different sizes, but total size of data described by the two arrays must + be the same +*/ +static int nfsd_copy_iovec(const struct iovec* svec, const unsigned int scount, + struct iovec* dvec, const unsigned int dcount, size_t size) { + size_t cur_size, soff, doff, tocopy, srem , drem ; + unsigned int di, si; + + cur_size = iov_length(svec, scount); + if (cur_size != iov_length(dvec, dcount)) + return -EINVAL; + + srem = drem = 0; + di = si = 0; + soff = doff = 0; + while (cur_size > 0) { + if (si >= scount || di >= dcount) + return -EFAULT; + + srem = svec[si].iov_len - soff; + drem = dvec[di].iov_len - doff; + tocopy = (srem > drem) ? drem : srem; + memcpy((char*)(dvec[di].iov_base) + doff, (char*)(svec[si].iov_base) + soff, tocopy); + cur_size -= tocopy; + srem -= tocopy; + drem -= tocopy; + doff += tocopy; + soff += tocopy; + if (srem == 0) { + si++; + soff = 0; + } + if (drem == 0) { + di++; + doff = 0; + } + } + if (si != scount || di != dcount || srem !=0 || drem != 0) + { + printk(KERN_WARNING"In copy_iovec: si=%lu, scount=%lu, di=%lu, dcount=%lu, srem=%lu, drem=%lu", + (unsigned long)si, (unsigned long)scount, (unsigned long)di, + (unsigned long)dcount, (unsigned long)srem, (unsigned long)drem); + return -EFAULT; + } + + return 0; +} + +/* + Allocates iovec array where each element has memory page-aligned base address + and size of a page. Needed for DIRECT I/O to be possbile from this array + */ +static int nfsd_allocate_paged_iovec(size_t size, unsigned int* pcount, + struct iovec** pvec) { + unsigned int i; + unsigned int page_num = size / PAGE_SIZE; + struct iovec * vec = NULL; + + *pvec = NULL; + *pcount = 0; + if (page_num * PAGE_SIZE != size) + page_num++; + + vec = kmalloc(sizeof(struct iovec) * page_num, GFP_KERNEL); + if (!vec) + return -ENOMEM; + memset(vec, 0, sizeof(struct iovec) * page_num); + *pvec = vec; + *pcount = page_num; + + for (i = 0; i < page_num; i++) { + vec[i].iov_base = (void*)__get_free_page(GFP_KERNEL); + if (!vec[i].iov_base) + return -ENOMEM; + vec[i].iov_len = PAGE_SIZE; + } + + if (size % PAGE_SIZE) + vec[page_num - 1].iov_len = size % PAGE_SIZE; + + return 0; +} + +/* + Deallocates iovec array, allocated by nfsd_allocate_paged_iovec +*/ +static void nfsd_free_paged_iovec(unsigned int count, struct iovec* vec) { + unsigned int i; + if (vec) { + for (i = 0; i < count; i++) + if (vec[i].iov_base) + free_page((unsigned long)(vec[i].iov_base)); + kfree(vec); + } +} + +/* + Performs direct I/O for a given NFS write request +*/ +static ssize_t nfsd_vfs_write_direct(struct file *file, const struct iovec *vec, + unsigned long vlen, loff_t *pos) { + ssize_t result = -EINVAL; + unsigned int page_num; + struct iovec *aligned_vec = NULL; + + // Check size to be multiple of sectors + size_t size = iov_length(vec, vlen); + + if (size == 0) + return vfs_writev(file, (struct iovec __user *)vec, vlen, pos); + + // Allocate necesary number of pages + result = nfsd_allocate_paged_iovec(size, &page_num, &aligned_vec); + if (result) { + printk(KERN_WARNING"Cannot allocate aligned_vec."); + goto out; + } + + // Copy data + result = nfsd_copy_iovec(vec, vlen, aligned_vec, page_num, size); + if(result) { + printk(KERN_WARNING"Wrong amount of data copied to aligned buffer."); + goto out; + } + + // Call further + result = vfs_writev(file, (struct iovec __user *)aligned_vec, page_num, pos); + +out: + nfsd_free_paged_iovec(page_num, aligned_vec); + return result; +} + + +/* + Performs direct I/O for a given NFS read request +*/ +static ssize_t nfsd_vfs_read_direct(struct file *file, struct iovec *vec, + unsigned long vlen, loff_t *pos) { + unsigned int page_num; + struct iovec *aligned_vec = NULL; + ssize_t result = -EINVAL; + size_t size; + + // Check size to be multiple of sectors + size = iov_length(vec, vlen); + + if (size == 0) + return vfs_readv(file, (struct iovec __user *)vec, vlen, pos); + + // Allocate necesary number of pages + result = nfsd_allocate_paged_iovec(size, &page_num, &aligned_vec); + if (result) { + printk(KERN_WARNING"Cannot allocate aligned_vec."); + goto out; + } + + // Call further + result = vfs_readv(file, (struct iovec __user *)aligned_vec, page_num, pos); + if (result < 0) { + printk(KERN_WARNING"Error during read operation."); + goto out; + } + + // Copy data + if(nfsd_copy_iovec(aligned_vec, page_num, vec, vlen, size)) { + printk(KERN_WARNING"Wrong amount of data copied from aligned buffer."); + goto out; + } + +out: + nfsd_free_paged_iovec(page_num, aligned_vec); + + return result; +} + +// Returns number of terminal zero bits for a given number (number alignment) +static unsigned int get_alignment(loff_t n) { + unsigned int i=0; + if (n == 0) + return (unsigned int)-1; // 0 is alligned to any number + while ((n & 1) == 0 && n > 0) { + n = n >> 1; + i++; + } + return i; +} + +// Returns the alignment of I/O request +static unsigned int io_alignment(const loff_t offset, + const unsigned long size) { + unsigned int i1, i2; + + i1 = get_alignment(offset); + i2 = get_alignment(size); + + return i1 > i2 ? i2 : i1; +} + + +/* + Based on the I/O request and file system parameters determines if + direct I/O can be used to perform the given request + Either file or sb are needed to retrieve file system and device + paramters +*/ +static int can_use_direct_io(const struct file *file, + const struct super_block* sb, + const loff_t offset, const unsigned long size) { + unsigned int blkbits = 0; + struct inode *inode; + unsigned int fsblkbits = 0; + unsigned int alignment = io_alignment(offset, size); + + if (alignment == 0) + return 0; + + if (file == NULL && sb == NULL) + return 0; + + if (nfsd_directio_mode == DIO_NEVER) + return 0; + + if (file != NULL && sb == NULL) { + inode = file->f_path.dentry->d_inode; + sb = inode->i_sb; + fsblkbits = inode->i_blkbits; + } + + if (sb !=NULL) { + blkbits = sb->s_blocksize_bits; + fsblkbits = sb->s_blocksize_bits; + if (sb->s_bdev) + blkbits = blksize_bits(bdev_logical_block_size(sb->s_bdev)); + } else + blkbits = fsblkbits; + + if (alignment >= fsblkbits && fsblkbits > 0 && nfsd_directio_mode != DIO_BDEV_ALIGNED) + return 0; + + if (alignment < blkbits) + return 0; + + return 1; +} + + /* * Open an existing file or directory. * The access argument indicates the type of open (read/write/lock) @@ -725,13 +975,15 @@ */ __be32 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, - int access, struct file **filp) + int access, struct file **filp, + const loff_t offset, const unsigned long size) { struct dentry *dentry; struct inode *inode; int flags = O_RDONLY|O_LARGEFILE; __be32 err; int host_err = 0; + struct super_block* sb; validate_process_creds(); @@ -774,6 +1026,11 @@ else flags = O_WRONLY|O_LARGEFILE; } + + sb = fhp->fh_export->ex_path.mnt->mnt_sb; + if (size && can_use_direct_io(NULL, sb, offset, size)) + flags |= O_DIRECT; + *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt), flags, current_cred()); if (IS_ERR(*filp)) @@ -885,8 +1142,10 @@ return __splice_from_pipe(pipe, sd, nfsd_splice_actor); } + + static __be32 -nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, + nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, loff_t offset, struct kvec *vec, int vlen, unsigned long *count) { mm_segment_t oldfs; @@ -899,21 +1158,29 @@ if (rqstp->rq_vers >= 3) file->f_flags |= O_NONBLOCK; - if (file->f_op->splice_read && rqstp->rq_splice_ok) { - struct splice_desc sd = { - .len = 0, - .total_len = *count, - .pos = offset, - .u.data = rqstp, - }; - - rqstp->rq_resused = 1; - host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor); - } else { + if (file->f_flags & O_DIRECT) { + // So far we do not support splice IO, so always do regular oldfs = get_fs(); set_fs(KERNEL_DS); - host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset); + host_err = nfsd_vfs_read_direct(file, (struct iovec*)vec, vlen, &offset); set_fs(oldfs); + } else { + if (file->f_op->splice_read && rqstp->rq_splice_ok) { + struct splice_desc sd = { + .len = 0, + .total_len = *count, + .pos = offset, + .u.data = rqstp, + }; + + rqstp->rq_resused = 1; + host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor); + } else { + oldfs = get_fs(); + set_fs(KERNEL_DS); + host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset); + set_fs(oldfs); + } } if (host_err >= 0) { @@ -1024,7 +1291,11 @@ /* Write the data. */ oldfs = get_fs(); set_fs(KERNEL_DS); - host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset); + if (file->f_flags & O_DIRECT) + host_err = nfsd_vfs_write_direct(file, (struct iovec*)vec, vlen, &offset); + else + host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset); + set_fs(oldfs); if (host_err < 0) goto out_nfserr; @@ -1064,8 +1335,9 @@ struct inode *inode; struct raparms *ra; __be32 err; + unsigned long size = iov_length((struct iovec*)vec, vlen); - err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file); + err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file, offset, size); if (err) return err; @@ -1133,7 +1405,8 @@ err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt, stablep); } else { - err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file); + unsigned long size = iov_length((struct iovec*)vec, vlen); + err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file, offset, size); if (err) goto out; @@ -1173,7 +1446,7 @@ } err = nfsd_open(rqstp, fhp, S_IFREG, - NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &file); + NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &file, 0, 0); if (err) goto out; if (EX_ISSYNC(fhp->fh_export)) { @@ -2018,7 +2291,7 @@ struct file *file; loff_t offset = *offsetp; - err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file); + err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file, 0, 0); if (err) goto out; diff -uNr linux-orig/fs/nfsd/vfs.h linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/vfs.h --- linux-orig/fs/nfsd/vfs.h 2011-10-24 14:06:32.000000000 -0400 +++ linux-3.0.7-0.7.2.8796.vmw/fs/nfsd/vfs.h 2012-03-28 15:40:29.000000000 -0400 @@ -66,7 +66,7 @@ loff_t, unsigned long); #endif /* CONFIG_NFSD_V3 */ __be32 nfsd_open(struct svc_rqst *, struct svc_fh *, int, - int, struct file **); + int, struct file **, const loff_t, const unsigned long); void nfsd_close(struct file *); __be32 nfsd_read(struct svc_rqst *, struct svc_fh *, loff_t, struct kvec *, int, unsigned long *);