[PATCH] Vectorize aio_read/aio_write fileop methods

This patch vectorizes aio_read() and aio_write() methods to prepare for
collapsing all aio & vectored operations into one interface - which is
aio_read()/aio_write().

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Michael Holzheu <HOLZHEU@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

11 files changed, 113 insertions, 89 deletions

diff --git a/fs/aio.c b/fs/aio.c
index 950630187acc..27ff56540c73 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -15,6 +15,7 @@
 #include <linux/aio_abi.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
+#include <linux/uio.h>
 
 #define DEBUG 0
 
@@ -1315,8 +1316,11 @@ static ssize_t aio_pread(struct kiocb *iocb)
         ssize_t ret = 0;
 
         do {
-                ret = file->f_op->aio_read(iocb, iocb->ki_buf,
-                        iocb->ki_left, iocb->ki_pos);
+                iocb->ki_inline_vec.iov_base = iocb->ki_buf;
+                iocb->ki_inline_vec.iov_len = iocb->ki_left;
+
+                ret = file->f_op->aio_read(iocb, &iocb->ki_inline_vec,
+                                                1, iocb->ki_pos);
                 /*
                  * Can't just depend on iocb->ki_left to determine
                  * whether we are done. This may have been a short read.
@@ -1349,8 +1353,11 @@ static ssize_t aio_pwrite(struct kiocb *iocb)
         ssize_t ret = 0;
 
         do {
-                ret = file->f_op->aio_write(iocb, iocb->ki_buf,
-                        iocb->ki_left, iocb->ki_pos);
+                iocb->ki_inline_vec.iov_base = iocb->ki_buf;
+                iocb->ki_inline_vec.iov_len = iocb->ki_left;
+
+                ret = file->f_op->aio_write(iocb, &iocb->ki_inline_vec,
+                                                1, iocb->ki_pos);
                 if (ret > 0) {
                         iocb->ki_buf += ret;
                         iocb->ki_left -= ret;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 0c361ea7e5a6..8c819117310b 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1162,14 +1162,6 @@ static ssize_t blkdev_file_write(struct file *file, const char __user *buf,
         return generic_file_write_nolock(file, &local_iov, 1, ppos);
 }
 
-static ssize_t blkdev_file_aio_write(struct kiocb *iocb, const char __user *buf,
-                                   size_t count, loff_t pos)
-{
-        struct iovec local_iov = { .iov_base = (void __user *)buf, .iov_len = count };
-
-        return generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
-}
-
 static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
         return blkdev_ioctl(file->f_mapping->host, file, cmd, arg);
@@ -1192,7 +1184,7 @@ const struct file_operations def_blk_fops = {
         .read           = generic_file_read,
         .write          = blkdev_file_write,
         .aio_read       = generic_file_aio_read,
-        .aio_write      = blkdev_file_aio_write, 
+        .aio_write      = generic_file_aio_write_nolock,
         .mmap           = generic_file_mmap,
         .fsync          = block_fsync,
         .unlocked_ioctl = block_ioctl,
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 22bcf4d7e7ae..5abb42a7c53e 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -492,13 +492,13 @@ static ssize_t cifs_file_writev(struct file *file, const struct iovec *iov,
         return written;
 }
 
-static ssize_t cifs_file_aio_write(struct kiocb *iocb, const char __user *buf,
-                                   size_t count, loff_t pos)
+static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+                                   unsigned long nr_segs, loff_t pos)
 {
         struct inode *inode = iocb->ki_filp->f_dentry->d_inode;
         ssize_t written;
 
-        written = generic_file_aio_write(iocb, buf, count, pos);
+        written = generic_file_aio_write(iocb, iov, nr_segs, pos);
         if (!CIFS_I(inode)->clientCanCacheAll)
                 filemap_fdatawrite(inode->i_mapping);
         return written;
diff --git a/fs/ext3/file.c b/fs/ext3/file.c
index 74ff20f9d09b..5c762457bc89 100644
--- a/fs/ext3/file.c
+++ b/fs/ext3/file.c
@@ -48,14 +48,15 @@ static int ext3_release_file (struct inode * inode, struct file * filp)
 }
 
 static ssize_t
-ext3_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
+ext3_file_write(struct kiocb *iocb, const struct iovec *iov,
+                unsigned long nr_segs, loff_t pos)
 {
         struct file *file = iocb->ki_filp;
         struct inode *inode = file->f_dentry->d_inode;
         ssize_t ret;
         int err;
 
-        ret = generic_file_aio_write(iocb, buf, count, pos);
+        ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
 
         /*
          * Skip flushing if there was an error, or if nothing was written.
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 377839bed172..9f7f8b9ea1e2 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -707,8 +707,8 @@ static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, siz
 /**
  * nfs_file_direct_read - file direct read operation for NFS files
  * @iocb: target I/O control block
- * @buf: user's buffer into which to read data
- * @count: number of bytes to read
+ * @iov: vector of user buffers into which to read data
+ * @nr_segs: size of iov vector
  * @pos: byte offset in file where reading starts
  *
  * We use this function for direct reads instead of calling
@@ -725,17 +725,24 @@ static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, siz
  * client must read the updated atime from the server back into its
  * cache.
  */
-ssize_t nfs_file_direct_read(struct kiocb *iocb, char __user *buf, size_t count, loff_t pos)
+ssize_t nfs_file_direct_read(struct kiocb *iocb, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos)
 {
         ssize_t retval = -EINVAL;
         struct file *file = iocb->ki_filp;
         struct address_space *mapping = file->f_mapping;
+        /* XXX: temporary */
+        const char __user *buf = iov[0].iov_base;
+        size_t count = iov[0].iov_len;
 
         dprintk("nfs: direct read(%s/%s, %lu@%Ld)\n",
                 file->f_dentry->d_parent->d_name.name,
                 file->f_dentry->d_name.name,
                 (unsigned long) count, (long long) pos);
 
+        if (nr_segs != 1)
+                return -EINVAL;
+
         if (count < 0)
                 goto out;
         retval = -EFAULT;
@@ -760,8 +767,8 @@ out:
 /**
  * nfs_file_direct_write - file direct write operation for NFS files
  * @iocb: target I/O control block
- * @buf: user's buffer from which to write data
- * @count: number of bytes to write
+ * @iov: vector of user buffers from which to write data
+ * @nr_segs: size of iov vector
  * @pos: byte offset in file where writing starts
  *
  * We use this function for direct writes instead of calling
@@ -782,17 +789,24 @@ out:
  * Note that O_APPEND is not supported for NFS direct writes, as there
  * is no atomic O_APPEND write facility in the NFS protocol.
  */
-ssize_t nfs_file_direct_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
+ssize_t nfs_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos)
 {
         ssize_t retval;
         struct file *file = iocb->ki_filp;
         struct address_space *mapping = file->f_mapping;
+        /* XXX: temporary */
+        const char __user *buf = iov[0].iov_base;
+        size_t count = iov[0].iov_len;
 
         dfprintk(VFS, "nfs: direct write(%s/%s, %lu@%Ld)\n",
                 file->f_dentry->d_parent->d_name.name,
                 file->f_dentry->d_name.name,
                 (unsigned long) count, (long long) pos);
 
+        if (nr_segs != 1)
+                return -EINVAL;
+
         retval = generic_write_checks(file, &pos, &count, 0);
         if (retval)
                 goto out;
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index be997d649127..cc93865cea93 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -41,8 +41,10 @@ static int nfs_file_release(struct inode *, struct file *);
 static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin);
 static int  nfs_file_mmap(struct file *, struct vm_area_struct *);
 static ssize_t nfs_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
-static ssize_t nfs_file_read(struct kiocb *, char __user *, size_t, loff_t);
-static ssize_t nfs_file_write(struct kiocb *, const char __user *, size_t, loff_t);
+static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos);
+static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos);
 static int  nfs_file_flush(struct file *, fl_owner_t id);
 static int  nfs_fsync(struct file *, struct dentry *dentry, int datasync);
 static int nfs_check_flags(int flags);
@@ -53,8 +55,8 @@ const struct file_operations nfs_file_operations = {
         .llseek         = nfs_file_llseek,
         .read           = do_sync_read,
         .write          = do_sync_write,
-        .aio_read               = nfs_file_read,
-        .aio_write              = nfs_file_write,
+        .aio_read       = nfs_file_read,
+        .aio_write      = nfs_file_write,
         .mmap           = nfs_file_mmap,
         .open           = nfs_file_open,
         .flush          = nfs_file_flush,
@@ -196,15 +198,17 @@ nfs_file_flush(struct file *file, fl_owner_t id)
 }
 
 static ssize_t
-nfs_file_read(struct kiocb *iocb, char __user * buf, size_t count, loff_t pos)
+nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
+                unsigned long nr_segs, loff_t pos)
 {
         struct dentry * dentry = iocb->ki_filp->f_dentry;
         struct inode * inode = dentry->d_inode;
         ssize_t result;
+        size_t count = iov_length(iov, nr_segs);
 
 #ifdef CONFIG_NFS_DIRECTIO
         if (iocb->ki_filp->f_flags & O_DIRECT)
-                return nfs_file_direct_read(iocb, buf, count, pos);
+                return nfs_file_direct_read(iocb, iov, nr_segs, pos);
 #endif
 
         dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
@@ -214,7 +218,7 @@ nfs_file_read(struct kiocb *iocb, char __user * buf, size_t count, loff_t pos)
         result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
         nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
         if (!result)
-                result = generic_file_aio_read(iocb, buf, count, pos);
+                result = generic_file_aio_read(iocb, iov, nr_segs, pos);
         return result;
 }
 
@@ -336,24 +340,22 @@ const struct address_space_operations nfs_file_aops = {
 #endif
 };
 
-/* 
- * Write to a file (through the page cache).
- */
-static ssize_t
-nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
+static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos)
 {
         struct dentry * dentry = iocb->ki_filp->f_dentry;
         struct inode * inode = dentry->d_inode;
         ssize_t result;
+        size_t count = iov_length(iov, nr_segs);
 
 #ifdef CONFIG_NFS_DIRECTIO
         if (iocb->ki_filp->f_flags & O_DIRECT)
-                return nfs_file_direct_write(iocb, buf, count, pos);
+                return nfs_file_direct_write(iocb, iov, nr_segs, pos);
 #endif
 
-        dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%lu)\n",
+        dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
                 dentry->d_parent->d_name.name, dentry->d_name.name,
-                inode->i_ino, (unsigned long) count, (unsigned long) pos);
+                inode->i_ino, (unsigned long) count, (long long) pos);
 
         result = -EBUSY;
         if (IS_SWAPFILE(inode))
@@ -372,7 +374,7 @@ nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t
                 goto out;
 
         nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count);
-        result = generic_file_aio_write(iocb, buf, count, pos);
+        result = generic_file_aio_write(iocb, iov, nr_segs, pos);
 out:
         return result;
 
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 585a79d39c9d..0c46f5c86b71 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -2176,20 +2176,18 @@ out:
 /**
  * ntfs_file_aio_write -
  */
-static ssize_t ntfs_file_aio_write(struct kiocb *iocb, const char __user *buf,
-                size_t count, loff_t pos)
+static ssize_t ntfs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+                unsigned long nr_segs, loff_t pos)
 {
         struct file *file = iocb->ki_filp;
         struct address_space *mapping = file->f_mapping;
         struct inode *inode = mapping->host;
         ssize_t ret;
-        struct iovec local_iov = { .iov_base = (void __user *)buf,
-                                   .iov_len = count };
 
         BUG_ON(iocb->ki_pos != pos);
 
         mutex_lock(&inode->i_mutex);
-        ret = ntfs_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
+        ret = ntfs_file_aio_write_nolock(iocb, iov, nr_segs, &iocb->ki_pos);
         mutex_unlock(&inode->i_mutex);
         if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
                 int err = sync_page_range(inode, mapping, pos, ret);
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 2bbfa17090cf..d9ba0a931a03 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -961,25 +961,23 @@ static inline int ocfs2_write_should_remove_suid(struct inode *inode)
 }
 
 static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
-                                    const char __user *buf,
-                                    size_t count,
+                                    const struct iovec *iov,
+                                    unsigned long nr_segs,
                                     loff_t pos)
 {
-        struct iovec local_iov = { .iov_base = (void __user *)buf,
-                                   .iov_len = count };
         int ret, rw_level = -1, meta_level = -1, have_alloc_sem = 0;
         u32 clusters;
         struct file *filp = iocb->ki_filp;
         struct inode *inode = filp->f_dentry->d_inode;
         loff_t newsize, saved_pos;
 
-        mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
-                   (unsigned int)count,
+        mlog_entry("(0x%p, %u, '%.*s')\n", filp,
+                   (unsigned int)nr_segs,
                    filp->f_dentry->d_name.len,
                    filp->f_dentry->d_name.name);
 
         /* happy write of zero bytes */
-        if (count == 0)
+        if (iocb->ki_left == 0)
                 return 0;
 
         if (!inode) {
@@ -1048,7 +1046,7 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
                 } else {
                         saved_pos = iocb->ki_pos;
                 }
-                newsize = count + saved_pos;
+                newsize = iocb->ki_left + saved_pos;
 
                 mlog(0, "pos=%lld newsize=%lld cursize=%lld\n",
                      (long long) saved_pos, (long long) newsize,
@@ -1081,7 +1079,7 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
                 if (!clusters)
                         break;
 
-                ret = ocfs2_extend_file(inode, NULL, newsize, count);
+                ret = ocfs2_extend_file(inode, NULL, newsize, iocb->ki_left);
                 if (ret < 0) {
                         if (ret != -ENOSPC)
                                 mlog_errno(ret);
@@ -1098,7 +1096,7 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
         /* communicate with ocfs2_dio_end_io */
         ocfs2_iocb_set_rw_locked(iocb);
 
-        ret = generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
+        ret = generic_file_aio_write_nolock(iocb, iov, nr_segs, iocb->ki_pos);
 
         /* buffered aio wouldn't have proper lock coverage today */
         BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
@@ -1132,16 +1130,16 @@ out:
 }
 
 static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
-                                   char __user *buf,
-                                   size_t count,
+                                   const struct iovec *iov,
+                                   unsigned long nr_segs,
                                    loff_t pos)
 {
         int ret = 0, rw_level = -1, have_alloc_sem = 0;
         struct file *filp = iocb->ki_filp;
         struct inode *inode = filp->f_dentry->d_inode;
 
-        mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
-                   (unsigned int)count,
+        mlog_entry("(0x%p, %u, '%.*s')\n", filp,
+                   (unsigned int)nr_segs,
                    filp->f_dentry->d_name.len,
                    filp->f_dentry->d_name.name);
 
@@ -1185,7 +1183,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
         }
         ocfs2_meta_unlock(inode, 0);
 
-        ret = generic_file_aio_read(iocb, buf, count, iocb->ki_pos);
+        ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
         if (ret == -EINVAL)
                 mlog(ML_ERROR, "generic_file_aio_read returned -EINVAL\n");
 
diff --git a/fs/read_write.c b/fs/read_write.c
index d4cb3183c99c..679dd535380f 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -227,14 +227,20 @@ static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
 
 ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
 {
+        struct iovec iov = { .iov_base = buf, .iov_len = len };
         struct kiocb kiocb;
         ssize_t ret;
 
         init_sync_kiocb(&kiocb, filp);
         kiocb.ki_pos = *ppos;
-        while (-EIOCBRETRY ==
-                (ret = filp->f_op->aio_read(&kiocb, buf, len, kiocb.ki_pos)))
+        kiocb.ki_left = len;
+
+        for (;;) {
+                ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
+                if (ret != -EIOCBRETRY)
+                        break;
                 wait_on_retry_sync_kiocb(&kiocb);
+        }
 
         if (-EIOCBQUEUED == ret)
                 ret = wait_on_sync_kiocb(&kiocb);
@@ -279,14 +285,20 @@ EXPORT_SYMBOL(vfs_read);
 
 ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
 {
+        struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
         struct kiocb kiocb;
         ssize_t ret;
 
         init_sync_kiocb(&kiocb, filp);
         kiocb.ki_pos = *ppos;
-        while (-EIOCBRETRY ==
-               (ret = filp->f_op->aio_write(&kiocb, buf, len, kiocb.ki_pos)))
+        kiocb.ki_left = len;
+
+        for (;;) {
+                ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
+                if (ret != -EIOCBRETRY)
+                        break;
                 wait_on_retry_sync_kiocb(&kiocb);
+        }
 
         if (-EIOCBQUEUED == ret)
                 ret = wait_on_sync_kiocb(&kiocb);
diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c
index c11f6118c9ca..41f24369e47a 100644
--- a/fs/reiserfs/file.c
+++ b/fs/reiserfs/file.c
@@ -1334,7 +1334,7 @@ static ssize_t reiserfs_file_write(struct file *file,	/* the file we are going t
                         if (err)
                                 return err;
                 }
-                result = generic_file_write(file, buf, count, ppos);
+                result = do_sync_write(file, buf, count, ppos);
 
                 if (after_file_end) {   /* Now update i_size and remove the savelink */
                         struct reiserfs_transaction_handle th;
@@ -1566,7 +1566,7 @@ static ssize_t reiserfs_file_write(struct file *file,	/* the file we are going t
 }
 
 const struct file_operations reiserfs_file_operations = {
-        .read = generic_file_read,
+        .read = do_sync_read,
         .write = reiserfs_file_write,
         .ioctl = reiserfs_ioctl,
 #ifdef CONFIG_COMPAT
diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 41cfcba7ce49..4737971c6a39 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -49,50 +49,49 @@ static struct vm_operations_struct xfs_dmapi_file_vm_ops;
 STATIC inline ssize_t
 __xfs_file_read(
         struct kiocb            *iocb,
-        char                    __user *buf,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
         int                     ioflags,
-        size_t                  count,
         loff_t                  pos)
 {
-        struct iovec            iov = {buf, count};
         struct file             *file = iocb->ki_filp;
         bhv_vnode_t             *vp = vn_from_inode(file->f_dentry->d_inode);
 
         BUG_ON(iocb->ki_pos != pos);
         if (unlikely(file->f_flags & O_DIRECT))
                 ioflags |= IO_ISDIRECT;
-        return bhv_vop_read(vp, iocb, &iov, 1, &iocb->ki_pos, ioflags, NULL);
+        return bhv_vop_read(vp, iocb, iov, nr_segs, &iocb->ki_pos,
+                                ioflags, NULL);
 }
 
 STATIC ssize_t
 xfs_file_aio_read(
         struct kiocb            *iocb,
-        char                    __user *buf,
-        size_t                  count,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
         loff_t                  pos)
 {
-        return __xfs_file_read(iocb, buf, IO_ISAIO, count, pos);
+        return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO, pos);
 }
 
 STATIC ssize_t
 xfs_file_aio_read_invis(
         struct kiocb            *iocb,
-        char                    __user *buf,
-        size_t                  count,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
         loff_t                  pos)
 {
-        return __xfs_file_read(iocb, buf, IO_ISAIO|IO_INVIS, count, pos);
+        return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
 }
 
 STATIC inline ssize_t
 __xfs_file_write(
-        struct kiocb    *iocb,
-        const char      __user *buf,
-        int             ioflags,
-        size_t          count,
-        loff_t          pos)
+        struct kiocb            *iocb,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
+        int                     ioflags,
+        loff_t                  pos)
 {
-        struct iovec    iov = {(void __user *)buf, count};
         struct file     *file = iocb->ki_filp;
         struct inode    *inode = file->f_mapping->host;
         bhv_vnode_t     *vp = vn_from_inode(inode);
@@ -100,27 +99,28 @@ __xfs_file_write(
         BUG_ON(iocb->ki_pos != pos);
         if (unlikely(file->f_flags & O_DIRECT))
                 ioflags |= IO_ISDIRECT;
-        return bhv_vop_write(vp, iocb, &iov, 1, &iocb->ki_pos, ioflags, NULL);
+        return bhv_vop_write(vp, iocb, iov, nr_segs, &iocb->ki_pos,
+                                ioflags, NULL);
 }
 
 STATIC ssize_t
 xfs_file_aio_write(
         struct kiocb            *iocb,
-        const char              __user *buf,
-        size_t                  count,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
         loff_t                  pos)
 {
-        return __xfs_file_write(iocb, buf, IO_ISAIO, count, pos);
+        return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO, pos);
 }
 
 STATIC ssize_t
 xfs_file_aio_write_invis(
         struct kiocb            *iocb,
-        const char              __user *buf,
-        size_t                  count,
+        const struct iovec      *iov,
+        unsigned long           nr_segs,
         loff_t                  pos)
 {
-        return __xfs_file_write(iocb, buf, IO_ISAIO|IO_INVIS, count, pos);
+        return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
 }
 
 STATIC inline ssize_t