// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2019, Intel Corporation. */

#include "ice_common.h"
#include "ice_flow.h"

/* Describe properties of a protocol header field */
struct ice_flow_field_info {
	enum ice_flow_seg_hdr hdr;
	s16 off;	/* Offset from start of a protocol header, in bits */
	u16 size;	/* Size of fields in bits */
};

#define ICE_FLOW_FLD_INFO(_hdr, _offset_bytes, _size_bytes) { \
	.hdr = _hdr, \
	.off = (_offset_bytes) * BITS_PER_BYTE, \
	.size = (_size_bytes) * BITS_PER_BYTE, \
}

/* Table containing properties of supported protocol header fields */
static const
struct ice_flow_field_info ice_flds_info[ICE_FLOW_FIELD_IDX_MAX] = {
	/* IPv4 / IPv6 */
	/* ICE_FLOW_FIELD_IDX_IPV4_SA */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_IPV4, 12, sizeof(struct in_addr)),
	/* ICE_FLOW_FIELD_IDX_IPV4_DA */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_IPV4, 16, sizeof(struct in_addr)),
	/* ICE_FLOW_FIELD_IDX_IPV6_SA */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_IPV6, 8, sizeof(struct in6_addr)),
	/* ICE_FLOW_FIELD_IDX_IPV6_DA */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_IPV6, 24, sizeof(struct in6_addr)),
	/* Transport */
	/* ICE_FLOW_FIELD_IDX_TCP_SRC_PORT */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_TCP, 0, sizeof(__be16)),
	/* ICE_FLOW_FIELD_IDX_TCP_DST_PORT */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_TCP, 2, sizeof(__be16)),
	/* ICE_FLOW_FIELD_IDX_UDP_SRC_PORT */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_UDP, 0, sizeof(__be16)),
	/* ICE_FLOW_FIELD_IDX_UDP_DST_PORT */
	ICE_FLOW_FLD_INFO(ICE_FLOW_SEG_HDR_UDP, 2, sizeof(__be16)),
};

/**
 * ice_flow_set_fld_ext - specifies locations of field from entry's input buffer
 * @seg: packet segment the field being set belongs to
 * @fld: field to be set
 * @type: type of the field
 * @val_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of the value to match from
 *           entry's input buffer
 * @mask_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of mask value from entry's
 *            input buffer
 * @last_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of last/upper value from
 *            entry's input buffer
 *
 * This helper function stores information of a field being matched, including
 * the type of the field and the locations of the value to match, the mask, and
 * and the upper-bound value in the start of the input buffer for a flow entry.
 * This function should only be used for fixed-size data structures.
 *
 * This function also opportunistically determines the protocol headers to be
 * present based on the fields being set. Some fields cannot be used alone to
 * determine the protocol headers present. Sometimes, fields for particular
 * protocol headers are not matched. In those cases, the protocol headers
 * must be explicitly set.
 */
static void
ice_flow_set_fld_ext(struct ice_flow_seg_info *seg, enum ice_flow_field fld,
		     enum ice_flow_fld_match_type type, u16 val_loc,
		     u16 mask_loc, u16 last_loc)
{
	u64 bit = BIT_ULL(fld);

	seg->match |= bit;
	if (type == ICE_FLOW_FLD_TYPE_RANGE)
		seg->range |= bit;

	seg->fields[fld].type = type;
	seg->fields[fld].src.val = val_loc;
	seg->fields[fld].src.mask = mask_loc;
	seg->fields[fld].src.last = last_loc;

	ICE_FLOW_SET_HDRS(seg, ice_flds_info[fld].hdr);
}

/**
 * ice_flow_set_fld - specifies locations of field from entry's input buffer
 * @seg: packet segment the field being set belongs to
 * @fld: field to be set
 * @val_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of the value to match from
 *           entry's input buffer
 * @mask_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of mask value from entry's
 *            input buffer
 * @last_loc: if not ICE_FLOW_FLD_OFF_INVAL, location of last/upper value from
 *            entry's input buffer
 * @range: indicate if field being matched is to be in a range
 *
 * This function specifies the locations, in the form of byte offsets from the
 * start of the input buffer for a flow entry, from where the value to match,
 * the mask value, and upper value can be extracted. These locations are then
 * stored in the flow profile. When adding a flow entry associated with the
 * flow profile, these locations will be used to quickly extract the values and
 * create the content of a match entry. This function should only be used for
 * fixed-size data structures.
 */
static void
ice_flow_set_fld(struct ice_flow_seg_info *seg, enum ice_flow_field fld,
		 u16 val_loc, u16 mask_loc, u16 last_loc, bool range)
{
	enum ice_flow_fld_match_type t = range ?
		ICE_FLOW_FLD_TYPE_RANGE : ICE_FLOW_FLD_TYPE_REG;

	ice_flow_set_fld_ext(seg, fld, t, val_loc, mask_loc, last_loc);
}

#define ICE_FLOW_RSS_SEG_HDR_L3_MASKS \
	(ICE_FLOW_SEG_HDR_IPV4 | ICE_FLOW_SEG_HDR_IPV6)

#define ICE_FLOW_RSS_SEG_HDR_L4_MASKS \
	(ICE_FLOW_SEG_HDR_TCP | ICE_FLOW_SEG_HDR_UDP | ICE_FLOW_SEG_HDR_SCTP)

#define ICE_FLOW_RSS_SEG_HDR_VAL_MASKS \
	(ICE_FLOW_RSS_SEG_HDR_L3_MASKS | \
	 ICE_FLOW_RSS_SEG_HDR_L4_MASKS)

/**
 * ice_flow_set_rss_seg_info - setup packet segments for RSS
 * @segs: pointer to the flow field segment(s)
 * @hash_fields: fields to be hashed on for the segment(s)
 * @flow_hdr: protocol header fields within a packet segment
 *
 * Helper function to extract fields from hash bitmap and use flow
 * header value to set flow field segment for further use in flow
 * profile entry or removal.
 */
static enum ice_status
ice_flow_set_rss_seg_info(struct ice_flow_seg_info *segs, u64 hash_fields,
			  u32 flow_hdr)
{
	u64 val;
	u8 i;

	for_each_set_bit(i, (unsigned long *)&hash_fields,
			 ICE_FLOW_FIELD_IDX_MAX)
		ice_flow_set_fld(segs, (enum ice_flow_field)i,
				 ICE_FLOW_FLD_OFF_INVAL, ICE_FLOW_FLD_OFF_INVAL,
				 ICE_FLOW_FLD_OFF_INVAL, false);

	ICE_FLOW_SET_HDRS(segs, flow_hdr);

	if (segs->hdrs & ~ICE_FLOW_RSS_SEG_HDR_VAL_MASKS)
		return ICE_ERR_PARAM;

	val = (u64)(segs->hdrs & ICE_FLOW_RSS_SEG_HDR_L3_MASKS);
	if (val && !is_power_of_2(val))
		return ICE_ERR_CFG;

	val = (u64)(segs->hdrs & ICE_FLOW_RSS_SEG_HDR_L4_MASKS);
	if (val && !is_power_of_2(val))
		return ICE_ERR_CFG;

	return 0;
}

#define ICE_RSS_OUTER_HEADERS	1

/**
 * ice_add_rss_cfg_sync - add an RSS configuration
 * @hashed_flds: hash bit fields (ICE_FLOW_HASH_*) to configure
 * @addl_hdrs: protocol header fields
 * @segs_cnt: packet segment count
 *
 * Assumption: lock has already been acquired for RSS list
 */
static enum ice_status
ice_add_rss_cfg_sync(u64 hashed_flds, u32 addl_hdrs, u8 segs_cnt)
{
	struct ice_flow_seg_info *segs;
	enum ice_status status;

	if (!segs_cnt || segs_cnt > ICE_FLOW_SEG_MAX)
		return ICE_ERR_PARAM;

	segs = kcalloc(segs_cnt, sizeof(*segs), GFP_KERNEL);
	if (!segs)
		return ICE_ERR_NO_MEMORY;

	/* Construct the packet segment info from the hashed fields */
	status = ice_flow_set_rss_seg_info(&segs[segs_cnt - 1], hashed_flds,
					   addl_hdrs);

	kfree(segs);
	return status;
}

/**
 * ice_add_rss_cfg - add an RSS configuration with specified hashed fields
 * @hw: pointer to the hardware structure
 * @vsi_handle: software VSI handle
 * @hashed_flds: hash bit fields (ICE_FLOW_HASH_*) to configure
 * @addl_hdrs: protocol header fields
 *
 * This function will generate a flow profile based on fields associated with
 * the input fields to hash on, the flow type and use the VSI number to add
 * a flow entry to the profile.
 */
enum ice_status
ice_add_rss_cfg(struct ice_hw *hw, u16 vsi_handle, u64 hashed_flds,
		u32 addl_hdrs)
{
	enum ice_status status;

	if (hashed_flds == ICE_HASH_INVALID ||
	    !ice_is_vsi_valid(hw, vsi_handle))
		return ICE_ERR_PARAM;

	mutex_lock(&hw->rss_locks);
	status = ice_add_rss_cfg_sync(hashed_flds, addl_hdrs,
				      ICE_RSS_OUTER_HEADERS);
	mutex_unlock(&hw->rss_locks);

	return status;
}

/**
 * ice_replay_rss_cfg - replay RSS configurations associated with VSI
 * @hw: pointer to the hardware structure
 * @vsi_handle: software VSI handle
 */
enum ice_status ice_replay_rss_cfg(struct ice_hw *hw, u16 vsi_handle)
{
	enum ice_status status = 0;
	struct ice_rss_cfg *r;

	if (!ice_is_vsi_valid(hw, vsi_handle))
		return ICE_ERR_PARAM;

	mutex_lock(&hw->rss_locks);
	list_for_each_entry(r, &hw->rss_list_head, l_entry) {
		if (test_bit(vsi_handle, r->vsis)) {
			status = ice_add_rss_cfg_sync(r->hashed_flds,
						      r->packet_hdr,
						      ICE_RSS_OUTER_HEADERS);
			if (status)
				break;
		}
	}
	mutex_unlock(&hw->rss_locks);

	return status;
}