ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
void *buffer, size_t buffer_size)
{
ssize_t retval;
u64 attr_size;
struct p9_fid *attr_fid;
struct kvec kvec = {.iov_base = buffer, .iov_len = buffer_size};
struct iov_iter to;
int err;
iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buffer_size);
attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
if (IS_ERR(attr_fid)) {
retval = PTR_ERR(attr_fid);
p9_debug(P9_DEBUG_VFS, "p9_client_attrwalk failed %zd\n",
retval);
return retval;
}
if (attr_size > buffer_size) {
if (!buffer_size) /* request to get the attr_size */
retval = attr_size;
else
retval = -ERANGE;
} else {
iov_iter_truncate(&to, attr_size);
retval = p9_client_read(attr_fid, 0, &to, &err);
if (err)
retval = err;
}
p9_client_clunk(attr_fid);
return retval;
}
/**
* 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_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
u64 offset)
{
int n, total, size;
P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
n = 0;
total = 0;
size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
do {
n = p9_client_read(fid, data, udata, offset, count);
if (n <= 0)
break;
if (data)
data += n;
if (udata)
udata += n;
offset += n;
count -= n;
total += n;
} while (count > 0 && n == size);
if (n < 0)
total = n;
return total;
}
static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
{
bool over;
struct p9_wstat st;
int err = 0;
struct p9_fid *fid;
int buflen;
int reclen = 0;
struct p9_rdir *rdir;
struct kvec kvec;
p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
fid = file->private_data;
buflen = fid->clnt->msize - P9_IOHDRSZ;
rdir = v9fs_alloc_rdir_buf(file, buflen);
if (!rdir)
return -ENOMEM;
kvec.iov_base = rdir->buf;
kvec.iov_len = buflen;
while (1) {
if (rdir->tail == rdir->head) {
struct iov_iter to;
int n;
iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buflen);
n = p9_client_read(file->private_data, ctx->pos, &to,
&err);
if (err)
return err;
rdir->head = 0;
rdir->tail = n;
}
while (rdir->head < rdir->tail) {
p9stat_init(&st);
err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
rdir->tail - rdir->head, &st);
if (err) {
p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
p9stat_free(&st);
return -EIO;
}
reclen = st.size+2;
over = !dir_emit(ctx, st.name, strlen(st.name),
v9fs_qid2ino(&st.qid), dt_type(&st));
p9stat_free(&st);
if (over)
return 0;
rdir->head += reclen;
ctx->pos += reclen;
}
}
}
ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
void *buffer, size_t buffer_size)
{
ssize_t retval;
int msize, read_count;
u64 offset = 0, attr_size;
struct p9_fid *attr_fid;
attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
if (IS_ERR(attr_fid)) {
retval = PTR_ERR(attr_fid);
P9_DPRINTK(P9_DEBUG_VFS,
"p9_client_attrwalk failed %zd\n", retval);
attr_fid = NULL;
goto error;
}
if (!buffer_size) {
/* request to get the attr_size */
retval = attr_size;
goto error;
}
if (attr_size > buffer_size) {
retval = -ERANGE;
goto error;
}
msize = attr_fid->clnt->msize;
while (attr_size) {
if (attr_size > (msize - P9_IOHDRSZ))
read_count = msize - P9_IOHDRSZ;
else
read_count = attr_size;
read_count = p9_client_read(attr_fid, ((char *)buffer)+offset,
NULL, offset, read_count);
if (read_count < 0) {
/* error in xattr read */
retval = read_count;
goto error;
}
offset += read_count;
attr_size -= read_count;
}
/* Total read xattr bytes */
retval = offset;
error:
if (attr_fid)
p9_client_clunk(attr_fid);
return retval;
}
static ssize_t
v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
struct p9_fid *fid = iocb->ki_filp->private_data;
int ret, err = 0;
p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
iov_iter_count(to), iocb->ki_pos);
ret = p9_client_read(fid, iocb->ki_pos, to, &err);
if (!ret)
return err;
iocb->ki_pos += ret;
return ret;
}
static ssize_t
v9fs_file_read(struct file *filp, char __user *udata, size_t count,
loff_t * offset)
{
int ret;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
fid = filp->private_data;
if (count > (fid->clnt->msize - P9_IOHDRSZ))
ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
else
ret = p9_client_read(fid, NULL, udata, *offset, count);
if (ret > 0)
*offset += ret;
return ret;
}
int p9_client_readn(struct p9_fid *fid, char *data, u64 offset, u32 count)
{
int n, total;
P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
(long long unsigned) offset, count);
n = 0;
total = 0;
while (count) {
n = p9_client_read(fid, data, offset, count);
if (n <= 0)
break;
data += n;
offset += n;
count -= n;
total += n;
}
if (n < 0)
total = n;
return total;
}
