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>
This commit is contained in:
Aneesh Kumar K.V 2011-02-28 17:03:56 +05:30 committed by Eric Van Hensbergen
parent 2efda7998b
commit 17311779ac
2 changed files with 67 additions and 45 deletions

View File

@ -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)

View File

@ -323,25 +323,22 @@ static int v9fs_file_flock_dotl(struct file *filp, int cmd,
}
/**
* 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
@ -398,6 +411,45 @@ v9fs_file_read(struct file *filp, char __user *udata, size_t count,
return ret;
}
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)
{
int n;
size_t total = 0;
struct p9_client *clnt;
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);
clnt = fid->clnt;
do {
n = p9_client_write(fid, NULL, data+total, origin+total, count);
if (n <= 0)
break;
count -= n;
total += n;
} while (count > 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)
invalidate_inode_pages2_range(inode->i_mapping,
pg_start, pg_end);
*offset += total;
i_size_write(inode, i_size_read(inode) + total);
inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
}
if (n < 0)
return n;
return total;
}
/**
* v9fs_file_write - write to a file
* @filp: file pointer to write
@ -406,25 +458,13 @@ v9fs_file_read(struct file *filp, char __user *udata, size_t count,
* @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)
size_t count, loff_t *offset)
{
ssize_t retval;
size_t total = 0;
int n;
struct p9_fid *fid;
struct p9_client *clnt;
struct inode *inode = filp->f_path.dentry->d_inode;
ssize_t retval = 0;
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)
@ -437,29 +477,9 @@ v9fs_file_write(struct file *filp, const char __user * data,
if (!count)
goto out;
do {
n = p9_client_write(fid, NULL, data+total, origin+total, count);
if (n <= 0)
break;
count -= n;
total += n;
} while (count > 0);
if (total > 0) {
pg_start = origin >> PAGE_CACHE_SHIFT;
pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
if (inode->i_mapping && inode->i_mapping->nrpages)
invalidate_inode_pages2_range(inode->i_mapping,
pg_start, pg_end);
*offset += total;
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 v9fs_file_write_internal(filp->f_path.dentry->d_inode,
filp->private_data,
data, count, offset, 1);
out:
return retval;
}