client.c

linux 内核源代码

		}

		err = p9_conn_rpc(clnt->conn, tc, &rc);
		if (err)
			goto error;

		n = rc->params.rread.count;
		if (n > count)
			n = count;

		memmove(data, rc->params.rread.data, n);
		count -= n;
		data += n;
		offset += n;
		total += n;
		kfree(tc);
		tc = NULL;
		kfree(rc);
		rc = NULL;
	} while (count > 0 && n == rsize);

	return total;

error:
	kfree(tc);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(p9_client_read);

int p9_client_write(struct p9_fid *fid, char *data, u64 offset, u32 count)
{
	int err, n, rsize, total;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
					(long long unsigned) offset, count);
	err = 0;
	tc = NULL;
	rc = NULL;
	clnt = fid->clnt;
	total = 0;

	rsize = fid->iounit;
	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
		rsize = clnt->msize - P9_IOHDRSZ;

	do {
		if (count < rsize)
			rsize = count;

		tc = p9_create_twrite(fid->fid, offset, rsize, data);
		if (IS_ERR(tc)) {
			err = PTR_ERR(tc);
			tc = NULL;
			goto error;
		}

		err = p9_conn_rpc(clnt->conn, tc, &rc);
		if (err)
			goto error;

		n = rc->params.rread.count;
		count -= n;
		data += n;
		offset += n;
		total += n;
		kfree(tc);
		tc = NULL;
		kfree(rc);
		rc = NULL;
	} while (count > 0);

	return total;

error:
	kfree(tc);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(p9_client_write);

int
p9_client_uread(struct p9_fid *fid, char __user *data, u64 offset, u32 count)
{
	int err, n, rsize, total;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
					(long long unsigned) offset, count);
	err = 0;
	tc = NULL;
	rc = NULL;
	clnt = fid->clnt;
	total = 0;

	rsize = fid->iounit;
	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
		rsize = clnt->msize - P9_IOHDRSZ;

	do {
		if (count < rsize)
			rsize = count;

		tc = p9_create_tread(fid->fid, offset, rsize);
		if (IS_ERR(tc)) {
			err = PTR_ERR(tc);
			tc = NULL;
			goto error;
		}

		err = p9_conn_rpc(clnt->conn, tc, &rc);
		if (err)
			goto error;

		n = rc->params.rread.count;
		if (n > count)
			n = count;

		err = copy_to_user(data, rc->params.rread.data, n);
		if (err) {
			err = -EFAULT;
			goto error;
		}

		count -= n;
		data += n;
		offset += n;
		total += n;
		kfree(tc);
		tc = NULL;
		kfree(rc);
		rc = NULL;
	} while (count > 0 && n == rsize);

	return total;

error:
	kfree(tc);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(p9_client_uread);

int
p9_client_uwrite(struct p9_fid *fid, const char __user *data, u64 offset,
								   u32 count)
{
	int err, n, rsize, total;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu count %d\n", fid->fid,
					(long long unsigned) offset, count);
	err = 0;
	tc = NULL;
	rc = NULL;
	clnt = fid->clnt;
	total = 0;

	rsize = fid->iounit;
	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
		rsize = clnt->msize - P9_IOHDRSZ;

	do {
		if (count < rsize)
			rsize = count;

		tc = p9_create_twrite_u(fid->fid, offset, rsize, data);
		if (IS_ERR(tc)) {
			err = PTR_ERR(tc);
			tc = NULL;
			goto error;
		}

		err = p9_conn_rpc(clnt->conn, tc, &rc);
		if (err)
			goto error;

		n = rc->params.rread.count;
		count -= n;
		data += n;
		offset += n;
		total += n;
		kfree(tc);
		tc = NULL;
		kfree(rc);
		rc = NULL;
	} while (count > 0);

	return total;

error:
	kfree(tc);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(p9_client_uwrite);

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;
}
EXPORT_SYMBOL(p9_client_readn);

struct p9_stat *p9_client_stat(struct p9_fid *fid)
{
	int err;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;
	struct p9_stat *ret;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
	err = 0;
	tc = NULL;
	rc = NULL;
	ret = NULL;
	clnt = fid->clnt;

	tc = p9_create_tstat(fid->fid);
	if (IS_ERR(tc)) {
		err = PTR_ERR(tc);
		tc = NULL;
		goto error;
	}

	err = p9_conn_rpc(clnt->conn, tc, &rc);
	if (err)
		goto error;

	ret = p9_clone_stat(&rc->params.rstat.stat, clnt->dotu);
	if (IS_ERR(ret)) {
		err = PTR_ERR(ret);
		ret = NULL;
		goto error;
	}

	kfree(tc);
	kfree(rc);
	return ret;

error:
	kfree(tc);
	kfree(rc);
	kfree(ret);
	return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_stat);

int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
{
	int err;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
	err = 0;
	tc = NULL;
	rc = NULL;
	clnt = fid->clnt;

	tc = p9_create_twstat(fid->fid, wst, clnt->dotu);
	if (IS_ERR(tc)) {
		err = PTR_ERR(tc);
		tc = NULL;
		goto done;
	}

	err = p9_conn_rpc(clnt->conn, tc, &rc);

done:
	kfree(tc);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(p9_client_wstat);

struct p9_stat *p9_client_dirread(struct p9_fid *fid, u64 offset)
{
	int err, n, m;
	struct p9_fcall *tc, *rc;
	struct p9_client *clnt;
	struct p9_stat st, *ret;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d offset %llu\n", fid->fid,
						(long long unsigned) offset);
	err = 0;
	tc = NULL;
	rc = NULL;
	ret = NULL;
	clnt = fid->clnt;

	/* if the offset is below or above the current response, free it */
	if (offset < fid->rdir_fpos || (fid->rdir_fcall &&
		offset >= fid->rdir_fpos+fid->rdir_fcall->params.rread.count)) {
		fid->rdir_pos = 0;
		if (fid->rdir_fcall)
			fid->rdir_fpos += fid->rdir_fcall->params.rread.count;

		kfree(fid->rdir_fcall);
		fid->rdir_fcall = NULL;
		if (offset < fid->rdir_fpos)
			fid->rdir_fpos = 0;
	}

	if (!fid->rdir_fcall) {
		n = fid->iounit;
		if (!n || n > clnt->msize-P9_IOHDRSZ)
			n = clnt->msize - P9_IOHDRSZ;

		while (1) {
			if (fid->rdir_fcall) {
				fid->rdir_fpos +=
					fid->rdir_fcall->params.rread.count;
				kfree(fid->rdir_fcall);
				fid->rdir_fcall = NULL;
			}

			tc = p9_create_tread(fid->fid, fid->rdir_fpos, n);
			if (IS_ERR(tc)) {
				err = PTR_ERR(tc);
				tc = NULL;
				goto error;
			}

			err = p9_conn_rpc(clnt->conn, tc, &rc);
			if (err)
				goto error;

			n = rc->params.rread.count;
			if (n == 0)
				goto done;

			fid->rdir_fcall = rc;
			rc = NULL;
			if (offset >= fid->rdir_fpos &&
						offset < fid->rdir_fpos+n)
				break;
		}

		fid->rdir_pos = 0;
	}

	m = offset - fid->rdir_fpos;
	if (m < 0)
		goto done;

	n = p9_deserialize_stat(fid->rdir_fcall->params.rread.data + m,
		fid->rdir_fcall->params.rread.count - m, &st, clnt->dotu);

	if (!n) {
		err = -EIO;
		goto error;
	}

	fid->rdir_pos += n;
	st.size = n;
	ret = p9_clone_stat(&st, clnt->dotu);
	if (IS_ERR(ret)) {
		err = PTR_ERR(ret);
		ret = NULL;
		goto error;
	}

done:
	kfree(tc);
	kfree(rc);
	return ret;

error:
	kfree(tc);
	kfree(rc);
	kfree(ret);
	return ERR_PTR(err);
}
EXPORT_SYMBOL(p9_client_dirread);

static struct p9_stat *p9_clone_stat(struct p9_stat *st, int dotu)
{
	int n;
	char *p;
	struct p9_stat *ret;

	n = sizeof(struct p9_stat) + st->name.len + st->uid.len + st->gid.len +
		st->muid.len;

	if (dotu)
		n += st->extension.len;

	ret = kmalloc(n, GFP_KERNEL);
	if (!ret)
		return ERR_PTR(-ENOMEM);

	memmove(ret, st, sizeof(struct p9_stat));
	p = ((char *) ret) + sizeof(struct p9_stat);
	memmove(p, st->name.str, st->name.len);
	p += st->name.len;
	memmove(p, st->uid.str, st->uid.len);
	p += st->uid.len;
	memmove(p, st->gid.str, st->gid.len);
	p += st->gid.len;
	memmove(p, st->muid.str, st->muid.len);
	p += st->muid.len;

	if (dotu) {
		memmove(p, st->extension.str, st->extension.len);
		p += st->extension.len;
	}

	return ret;
}

static struct p9_fid *p9_fid_create(struct p9_client *clnt)
{
	int err;
	struct p9_fid *fid;

	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
	if (!fid)
		return ERR_PTR(-ENOMEM);

	fid->fid = p9_idpool_get(clnt->fidpool);
	if (fid->fid < 0) {
		err = -ENOSPC;
		goto error;
	}

	memset(&fid->qid, 0, sizeof(struct p9_qid));
	fid->mode = -1;
	fid->rdir_fpos = 0;
	fid->rdir_pos = 0;
	fid->rdir_fcall = NULL;
	fid->uid = current->fsuid;
	fid->clnt = clnt;
	fid->aux = NULL;

	spin_lock(&clnt->lock);
	list_add(&fid->flist, &clnt->fidlist);
	spin_unlock(&clnt->lock);

	return fid;

error:
	kfree(fid);
	return ERR_PTR(err);
}

static void p9_fid_destroy(struct p9_fid *fid)
{
	struct p9_client *clnt;

	P9_DPRINTK(P9_DEBUG_9P, "fid %d\n", fid->fid);
	clnt = fid->clnt;
	p9_idpool_put(fid->fid, clnt->fidpool);
	spin_lock(&clnt->lock);
	list_del(&fid->flist);
	spin_unlock(&clnt->lock);
	kfree(fid->rdir_fcall);
	kfree(fid);
}