1 files changed, 295 insertions, 0 deletions
diff --git a/fs/nfsd/blocklayoutxdr.c b/fs/nfsd/blocklayoutxdr.c
new file mode 100644
index 000000000000..196ef4245604
--- /dev/null
+++ b/fs/nfsd/blocklayoutxdr.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2014-2016 Christoph Hellwig.
+ */
+#include <linux/sunrpc/svc.h>
+#include <linux/exportfs.h>
+#include <linux/iomap.h>
+#include <linux/nfs4.h>
+
+#include "nfsd.h"
+#include "blocklayoutxdr.h"
+#include "vfs.h"
+
+#define NFSDDBG_FACILITY	NFSDDBG_PNFS
+
+
+/**
+ * nfsd4_block_encode_layoutget - encode block/scsi layout extent array
+ * @xdr: stream for data encoding
+ * @lgp: layoutget content, actually an array of extents to encode
+ *
+ * Encode the opaque loc_body field in the layoutget response. Since the
+ * pnfs_block_layout4 and pnfs_scsi_layout4 structures on the wire are
+ * the same, this function is used by both layout drivers.
+ *
+ * Return values:
+ *   %nfs_ok: Success, all extents encoded into @xdr
+ *   %nfserr_toosmall: Not enough space in @xdr to encode all the data
+ */
+__be32
+nfsd4_block_encode_layoutget(struct xdr_stream *xdr,
+		const struct nfsd4_layoutget *lgp)
+{
+	const struct pnfs_block_layout *bl = lgp->lg_content;
+	u32 i, len = sizeof(__be32) + bl->nr_extents * PNFS_BLOCK_EXTENT_SIZE;
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, sizeof(__be32) + len);
+	if (!p)
+		return nfserr_toosmall;
+
+	*p++ = cpu_to_be32(len);
+	*p++ = cpu_to_be32(bl->nr_extents);
+
+	for (i = 0; i < bl->nr_extents; i++) {
+		const struct pnfs_block_extent *bex = bl->extents + i;
+
+		p = svcxdr_encode_deviceid4(p, &bex->vol_id);
+		p = xdr_encode_hyper(p, bex->foff);
+		p = xdr_encode_hyper(p, bex->len);
+		p = xdr_encode_hyper(p, bex->soff);
+		*p++ = cpu_to_be32(bex->es);
+	}
+
+	return nfs_ok;
+}
+
+static int
+nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
+{
+	__be32 *p;
+	int len;
+
+	switch (b->type) {
+	case PNFS_BLOCK_VOLUME_SIMPLE:
+		len = 4 + 4 + 8 + 4 + (XDR_QUADLEN(b->simple.sig_len) << 2);
+		p = xdr_reserve_space(xdr, len);
+		if (!p)
+			return -ETOOSMALL;
+
+		*p++ = cpu_to_be32(b->type);
+		*p++ = cpu_to_be32(1);	/* single signature */
+		p = xdr_encode_hyper(p, b->simple.offset);
+		p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
+		break;
+	case PNFS_BLOCK_VOLUME_SCSI:
+		len = 4 + 4 + 4 + 4 + (XDR_QUADLEN(b->scsi.designator_len) << 2) + 8;
+		p = xdr_reserve_space(xdr, len);
+		if (!p)
+			return -ETOOSMALL;
+
+		*p++ = cpu_to_be32(b->type);
+		*p++ = cpu_to_be32(b->scsi.code_set);
+		*p++ = cpu_to_be32(b->scsi.designator_type);
+		p = xdr_encode_opaque(p, b->scsi.designator, b->scsi.designator_len);
+		p = xdr_encode_hyper(p, b->scsi.pr_key);
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+
+	return len;
+}
+
+__be32
+nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
+		const struct nfsd4_getdeviceinfo *gdp)
+{
+	struct pnfs_block_deviceaddr *dev = gdp->gd_device;
+	int len = sizeof(__be32), ret, i;
+	__be32 *p;
+
+	/*
+	 * See paragraph 5 of RFC 8881 S18.40.3.
+	 */
+	if (!gdp->gd_maxcount) {
+		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
+			return nfserr_resource;
+		return nfs_ok;
+	}
+
+	p = xdr_reserve_space(xdr, len + sizeof(__be32));
+	if (!p)
+		return nfserr_resource;
+
+	for (i = 0; i < dev->nr_volumes; i++) {
+		ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
+		if (ret < 0)
+			return nfserrno(ret);
+		len += ret;
+	}
+
+	/*
+	 * Fill in the overall length and number of volumes at the beginning
+	 * of the layout.
+	 */
+	*p++ = cpu_to_be32(len);
+	*p++ = cpu_to_be32(dev->nr_volumes);
+	return 0;
+}
+
+/**
+ * nfsd4_block_decode_layoutupdate - decode the block layout extent array
+ * @xdr: subbuf set to the encoded array
+ * @iomapp: pointer to store the decoded extent array
+ * @nr_iomapsp: pointer to store the number of extents
+ * @block_size: alignment of extent offset and length
+ *
+ * This function decodes the opaque field of the layoutupdate4 structure
+ * in a layoutcommit request for the block layout driver. The field is
+ * actually an array of extents sent by the client. It also checks that
+ * the file offset, storage offset and length of each extent are aligned
+ * by @block_size.
+ *
+ * Return values:
+ *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
+ *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
+ *   %nfserr_inval: An unaligned extent found
+ *   %nfserr_delay: Failed to allocate memory for @iomapp
+ */
+__be32
+nfsd4_block_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
+		int *nr_iomapsp, u32 block_size)
+{
+	struct iomap *iomaps;
+	u32 nr_iomaps, expected, len, i;
+	__be32 nfserr;
+
+	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
+		return nfserr_bad_xdr;
+
+	len = sizeof(__be32) + xdr_stream_remaining(xdr);
+	expected = sizeof(__be32) + nr_iomaps * PNFS_BLOCK_EXTENT_SIZE;
+	if (len != expected)
+		return nfserr_bad_xdr;
+
+	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
+	if (!iomaps)
+		return nfserr_delay;
+
+	for (i = 0; i < nr_iomaps; i++) {
+		struct pnfs_block_extent bex;
+
+		if (nfsd4_decode_deviceid4(xdr, &bex.vol_id)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+
+		if (xdr_stream_decode_u64(xdr, &bex.foff)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (bex.foff & (block_size - 1)) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+
+		if (xdr_stream_decode_u64(xdr, &bex.len)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (bex.len & (block_size - 1)) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+
+		if (xdr_stream_decode_u64(xdr, &bex.soff)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (bex.soff & (block_size - 1)) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+
+		if (xdr_stream_decode_u32(xdr, &bex.es)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+
+		iomaps[i].offset = bex.foff;
+		iomaps[i].length = bex.len;
+	}
+
+	*iomapp = iomaps;
+	*nr_iomapsp = nr_iomaps;
+	return nfs_ok;
+fail:
+	kfree(iomaps);
+	return nfserr;
+}
+
+/**
+ * nfsd4_scsi_decode_layoutupdate - decode the scsi layout extent array
+ * @xdr: subbuf set to the encoded array
+ * @iomapp: pointer to store the decoded extent array
+ * @nr_iomapsp: pointer to store the number of extents
+ * @block_size: alignment of extent offset and length
+ *
+ * This function decodes the opaque field of the layoutupdate4 structure
+ * in a layoutcommit request for the scsi layout driver. The field is
+ * actually an array of extents sent by the client. It also checks that
+ * the offset and length of each extent are aligned by @block_size.
+ *
+ * Return values:
+ *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
+ *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
+ *   %nfserr_inval: An unaligned extent found
+ *   %nfserr_delay: Failed to allocate memory for @iomapp
+ */
+__be32
+nfsd4_scsi_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
+		int *nr_iomapsp, u32 block_size)
+{
+	struct iomap *iomaps;
+	u32 nr_iomaps, expected, len, i;
+	__be32 nfserr;
+
+	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
+		return nfserr_bad_xdr;
+
+	len = sizeof(__be32) + xdr_stream_remaining(xdr);
+	expected = sizeof(__be32) + nr_iomaps * PNFS_SCSI_RANGE_SIZE;
+	if (len != expected)
+		return nfserr_bad_xdr;
+
+	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
+	if (!iomaps)
+		return nfserr_delay;
+
+	for (i = 0; i < nr_iomaps; i++) {
+		u64 val;
+
+		if (xdr_stream_decode_u64(xdr, &val)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (val & (block_size - 1)) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+		iomaps[i].offset = val;
+
+		if (xdr_stream_decode_u64(xdr, &val)) {
+			nfserr = nfserr_bad_xdr;
+			goto fail;
+		}
+		if (val & (block_size - 1)) {
+			nfserr = nfserr_inval;
+			goto fail;
+		}
+		iomaps[i].length = val;
+	}
+
+	*iomapp = iomaps;
+	*nr_iomapsp = nr_iomaps;
+	return nfs_ok;
+fail:
+	kfree(iomaps);
+	return nfserr;
+}