1 files changed, 99 insertions, 43 deletions

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index afcab007a22b..5e8d82f6666b 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -263,17 +263,19 @@ static const struct rpc_call_ops nfs_read_direct_ops = {
  * handled automatically by nfs_direct_read_result().  Otherwise, if
  * no requests have been sent, just return an error.
  */
-static ssize_t nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos)
+static ssize_t nfs_direct_read_schedule_segment(struct nfs_direct_req *dreq,
+                                                const struct iovec *iov,
+                                                loff_t pos)
 {
         struct nfs_open_context *ctx = dreq->ctx;
         struct inode *inode = ctx->path.dentry->d_inode;
+        unsigned long user_addr = (unsigned long)iov->iov_base;
+        size_t count = iov->iov_len;
         size_t rsize = NFS_SERVER(inode)->rsize;
         unsigned int pgbase;
         int result;
         ssize_t started = 0;
 
-        get_dreq(dreq);
-
         do {
                 struct nfs_read_data *data;
                 size_t bytes;
@@ -347,15 +349,46 @@ static ssize_t nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned lo
                 count -= bytes;
         } while (count != 0);
 
+        if (started)
+                return started;
+        return result < 0 ? (ssize_t) result : -EFAULT;
+}
+
+static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
+                                              const struct iovec *iov,
+                                              unsigned long nr_segs,
+                                              loff_t pos)
+{
+        ssize_t result = -EINVAL;
+        size_t requested_bytes = 0;
+        unsigned long seg;
+
+        get_dreq(dreq);
+
+        for (seg = 0; seg < nr_segs; seg++) {
+                const struct iovec *vec = &iov[seg];
+                result = nfs_direct_read_schedule_segment(dreq, vec, pos);
+                if (result < 0)
+                        break;
+                requested_bytes += result;
+                if ((size_t)result < vec->iov_len)
+                        break;
+                pos += vec->iov_len;
+        }
+
         if (put_dreq(dreq))
                 nfs_direct_complete(dreq);
 
-        if (started)
+        if (requested_bytes != 0)
                 return 0;
-        return result < 0 ? (ssize_t) result : -EFAULT;
+
+        if (result < 0)
+                return result;
+        return -EIO;
 }
 
-static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos)
+static ssize_t nfs_direct_read(struct kiocb *iocb, const struct iovec *iov,
+                               unsigned long nr_segs, loff_t pos)
 {
         ssize_t result = 0;
         sigset_t oldset;
@@ -372,9 +405,8 @@ static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size
         if (!is_sync_kiocb(iocb))
                 dreq->iocb = iocb;
 
-        nfs_add_stats(inode, NFSIOS_DIRECTREADBYTES, count);
         rpc_clnt_sigmask(clnt, &oldset);
-        result = nfs_direct_read_schedule(dreq, user_addr, count, pos);
+        result = nfs_direct_read_schedule_iovec(dreq, iov, nr_segs, pos);
         if (!result)
                 result = nfs_direct_wait(dreq);
         rpc_clnt_sigunmask(clnt, &oldset);
@@ -601,17 +633,19 @@ static const struct rpc_call_ops nfs_write_direct_ops = {
  * handled automatically by nfs_direct_write_result().  Otherwise, if
  * no requests have been sent, just return an error.
  */
-static ssize_t nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos, int sync)
+static ssize_t nfs_direct_write_schedule_segment(struct nfs_direct_req *dreq,
+                                                 const struct iovec *iov,
+                                                 loff_t pos, int sync)
 {
         struct nfs_open_context *ctx = dreq->ctx;
         struct inode *inode = ctx->path.dentry->d_inode;
+        unsigned long user_addr = (unsigned long)iov->iov_base;
+        size_t count = iov->iov_len;
         size_t wsize = NFS_SERVER(inode)->wsize;
         unsigned int pgbase;
         int result;
         ssize_t started = 0;
 
-        get_dreq(dreq);
-
         do {
                 struct nfs_write_data *data;
                 size_t bytes;
@@ -689,15 +723,48 @@ static ssize_t nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned l
                 count -= bytes;
         } while (count != 0);
 
+        if (started)
+                return started;
+        return result < 0 ? (ssize_t) result : -EFAULT;
+}
+
+static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
+                                               const struct iovec *iov,
+                                               unsigned long nr_segs,
+                                               loff_t pos, int sync)
+{
+        ssize_t result = 0;
+        size_t requested_bytes = 0;
+        unsigned long seg;
+
+        get_dreq(dreq);
+
+        for (seg = 0; seg < nr_segs; seg++) {
+                const struct iovec *vec = &iov[seg];
+                result = nfs_direct_write_schedule_segment(dreq, vec,
+                                                           pos, sync);
+                if (result < 0)
+                        break;
+                requested_bytes += result;
+                if ((size_t)result < vec->iov_len)
+                        break;
+                pos += vec->iov_len;
+        }
+
         if (put_dreq(dreq))
-                nfs_direct_write_complete(dreq, inode);
+                nfs_direct_write_complete(dreq, dreq->inode);
 
-        if (started)
+        if (requested_bytes != 0)
                 return 0;
-        return result < 0 ? (ssize_t) result : -EFAULT;
+
+        if (result < 0)
+                return result;
+        return -EIO;
 }
 
-static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos)
+static ssize_t nfs_direct_write(struct kiocb *iocb, const struct iovec *iov,
+                                unsigned long nr_segs, loff_t pos,
+                                size_t count)
 {
         ssize_t result = 0;
         sigset_t oldset;
@@ -720,10 +787,8 @@ static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, siz
         if (!is_sync_kiocb(iocb))
                 dreq->iocb = iocb;
 
-        nfs_add_stats(inode, NFSIOS_DIRECTWRITTENBYTES, count);
-
         rpc_clnt_sigmask(clnt, &oldset);
-        result = nfs_direct_write_schedule(dreq, user_addr, count, pos, sync);
+        result = nfs_direct_write_schedule_iovec(dreq, iov, nr_segs, pos, sync);
         if (!result)
                 result = nfs_direct_wait(dreq);
         rpc_clnt_sigunmask(clnt, &oldset);
@@ -759,21 +824,16 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, const struct iovec *iov,
         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;
+        size_t count;
+
+        count = iov_length(iov, nr_segs);
+        nfs_add_stats(mapping->host, NFSIOS_DIRECTREADBYTES, count);
 
-        dprintk("nfs: direct read(%s/%s, %lu@%Ld)\n",
+        dprintk("nfs: direct read(%s/%s, %zd@%Ld)\n",
                 file->f_path.dentry->d_parent->d_name.name,
                 file->f_path.dentry->d_name.name,
-                (unsigned long) count, (long long) pos);
-
-        if (nr_segs != 1)
-                goto out;
+                count, (long long) pos);
 
-        retval = -EFAULT;
-        if (!access_ok(VERIFY_WRITE, buf, count))
-                goto out;
         retval = 0;
         if (!count)
                 goto out;
@@ -782,7 +842,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, const struct iovec *iov,
         if (retval)
                 goto out;
 
-        retval = nfs_direct_read(iocb, (unsigned long) buf, count, pos);
+        retval = nfs_direct_read(iocb, iov, nr_segs, pos);
         if (retval > 0)
                 iocb->ki_pos = pos + retval;
 
@@ -821,21 +881,21 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
         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;
+        size_t count;
+
+        count = iov_length(iov, nr_segs);
+        nfs_add_stats(mapping->host, NFSIOS_DIRECTWRITTENBYTES, count);
 
-        dprintk("nfs: direct write(%s/%s, %lu@%Ld)\n",
+        dfprintk(VFS, "nfs: direct write(%s/%s, %zd@%Ld)\n",
                 file->f_path.dentry->d_parent->d_name.name,
                 file->f_path.dentry->d_name.name,
-                (unsigned long) count, (long long) pos);
-
-        if (nr_segs != 1)
-                goto out;
+                count, (long long) pos);
 
         retval = generic_write_checks(file, &pos, &count, 0);
         if (retval)
                 goto out;
+        if (!count)
+                goto out;       /* return 0 */
 
         retval = -EINVAL;
         if ((ssize_t) count < 0)
@@ -844,15 +904,11 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
         if (!count)
                 goto out;
 
-        retval = -EFAULT;
-        if (!access_ok(VERIFY_READ, buf, count))
-                goto out;
-
         retval = nfs_sync_mapping(mapping);
         if (retval)
                 goto out;
 
-        retval = nfs_direct_write(iocb, (unsigned long) buf, count, pos);
+        retval = nfs_direct_write(iocb, iov, nr_segs, pos, count);
 
         if (retval > 0)
                 iocb->ki_pos = pos + retval;