fs/9p: Add read write helper function

We add read write helper function here which will
be used later by the mmap patch

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index e4d5540cbb7050347b35da277d08b52c389bedb3..c44aaa8bd2a3e421a6476ed7d8a32d25f444267f 100644 (file)
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -64,8 +64,10 @@ void v9fs_inode2stat(struct inode *inode, struct p9_wstat *stat);
 int v9fs_uflags2omode(int uflags, int extended);
 
 ssize_t v9fs_file_readn(struct file *, char *, char __user *, u32, u64);
+ssize_t v9fs_fid_readn(struct p9_fid *, char *, char __user *, u32, u64);
 void v9fs_blank_wstat(struct p9_wstat *wstat);
 int v9fs_vfs_setattr_dotl(struct dentry *, struct iattr *);
 int v9fs_file_fsync_dotl(struct file *filp, int datasync);
-
+ssize_t v9fs_file_write_internal(struct inode *, struct p9_fid *,
+                                const char __user *, size_t, loff_t *, int);
 #define P9_LOCK_TIMEOUT (30*HZ)

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index ce1eae48a127d63f180a8cfac9da2d6d90d37c4b..6e1e8f43edaceea3a7436b230c6307c90d7f16b1 100644 (file)
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -323,25 +323,22 @@ out_err:
 }
 
 /**
- * v9fs_file_readn - read from a file
- * @filp: file pointer to read
+ * v9fs_fid_readn - read from a fid
+ * @fid: fid to read
  * @data: data buffer to read data into
  * @udata: user data buffer to read data into
  * @count: size of buffer
  * @offset: offset at which to read data
  *
  */
-
 ssize_t
-v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
+v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
               u64 offset)
 {
        int n, total, size;
-       struct p9_fid *fid = filp->private_data;
 
        P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
-                                       (long long unsigned) offset, count);
-
+                  (long long unsigned) offset, count);
        n = 0;
        total = 0;
        size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
@@ -366,6 +363,22 @@ v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
        return total;
 }
 
+/**
+ * v9fs_file_readn - read from a file
+ * @filp: file pointer to read
+ * @data: data buffer to read data into
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+ssize_t
+v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
+              u64 offset)
+{
+       return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
+}
+
 /**
  * v9fs_file_read - read from a file
  * @filp: file pointer to read
@@ -398,45 +411,21 @@ v9fs_file_read(struct file *filp, char __user *udata, size_t count,
        return ret;
 }
 
-/**
- * v9fs_file_write - write to a file
- * @filp: file pointer to write
- * @data: data buffer to write data from
- * @count: size of buffer
- * @offset: offset at which to write data
- *
- */
-
-static ssize_t
-v9fs_file_write(struct file *filp, const char __user * data,
-               size_t count, loff_t * offset)
+ssize_t
+v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
+                        const char __user *data, size_t count,
+                        loff_t *offset, int invalidate)
 {
-       ssize_t retval;
-       size_t total = 0;
        int n;
-       struct p9_fid *fid;
+       size_t total = 0;
        struct p9_client *clnt;
-       struct inode *inode = filp->f_path.dentry->d_inode;
        loff_t origin = *offset;
        unsigned long pg_start, pg_end;
 
        P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
                (int)count, (int)*offset);
 
-       fid = filp->private_data;
        clnt = fid->clnt;
-
-       retval = generic_write_checks(filp, &origin, &count, 0);
-       if (retval)
-               goto out;
-
-       retval = -EINVAL;
-       if ((ssize_t) count < 0)
-               goto out;
-       retval = 0;
-       if (!count)
-               goto out;
-
        do {
                n = p9_client_write(fid, NULL, data+total, origin+total, count);
                if (n <= 0)
@@ -445,7 +434,7 @@ v9fs_file_write(struct file *filp, const char __user * data,
                total += n;
        } while (count > 0);
 
-       if (total > 0) {
+       if (invalidate && (total > 0)) {
                pg_start = origin >> PAGE_CACHE_SHIFT;
                pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
                if (inode->i_mapping && inode->i_mapping->nrpages)
@@ -455,11 +444,42 @@ v9fs_file_write(struct file *filp, const char __user * data,
                i_size_write(inode, i_size_read(inode) + total);
                inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
        }
-
        if (n < 0)
-               retval = n;
-       else
-               retval = total;
+               return n;
+
+       return total;
+}
+
+/**
+ * v9fs_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+static ssize_t
+v9fs_file_write(struct file *filp, const char __user * data,
+               size_t count, loff_t *offset)
+{
+       ssize_t retval = 0;
+       loff_t origin = *offset;
+
+
+       retval = generic_write_checks(filp, &origin, &count, 0);
+       if (retval)
+               goto out;
+
+       retval = -EINVAL;
+       if ((ssize_t) count < 0)
+               goto out;
+       retval = 0;
+       if (!count)
+               goto out;
+
+       return v9fs_file_write_internal(filp->f_path.dentry->d_inode,
+                                       filp->private_data,
+                                       data, count, offset, 1);
 out:
        return retval;
 }