[RFC PATCH -V1 5/7] fs/9p: Add read write helper function

Aneesh Kumar K.V
2011-01-29T19:27:31Z

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>
---
fs/9p/v9fs_vfs.h | 4 ++-
fs/9p/vfs_file.c | 100 ++++++++++++++++++++++++++++++++---------------------
2 files changed, 63 insertions(+), 41 deletions(-)

diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index e4d5540..276ad44 100644
--- 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 *, char *,
+ 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 ce1eae4..ecdd512 100644
--- 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;
@@ -367,6 +364,22 @@ v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
}

/**
+ * 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
* @udata: user data buffer to read data into
@@ -398,45 +411,20 @@ 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, char *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 +433,7 @@ 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)
@@ -457,9 +445,41 @@ v9fs_file_write(struct file *filp, const char __user * data,
}

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,
+ (char *)data, count, offset, 1);
out:
return retval;
}
--
1.7.1