9p: switch p9_client_read() to passing struct iov_iter *

... and make it loop

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2015-04-01 23:42:28 -04:00
parent 9565a54452
commit e1200fe68f
7 changed files with 110 additions and 185 deletions

View File

@@ -364,63 +364,6 @@ out_err:
return ret;
}
/**
* 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_debug(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;
}
/**
* 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
@@ -434,22 +377,20 @@ static ssize_t
v9fs_file_read(struct file *filp, char __user *udata, size_t count,
loff_t * offset)
{
int ret;
struct p9_fid *fid;
size_t size;
struct p9_fid *fid = filp->private_data;
struct iovec iov = {.iov_base = udata, .iov_len = count};
struct iov_iter to;
int ret, err;
iov_iter_init(&to, READ, &iov, 1, count);
p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
fid = filp->private_data;
size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
if (count > size)
ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
else
ret = p9_client_read(fid, NULL, udata, *offset, count);
if (ret > 0)
*offset += ret;
ret = p9_client_read(fid, *offset, &to, &err);
if (!ret)
return err;
*offset += ret;
return ret;
}