| Message ID | 1455721519-12049-1-git-send-email-paul.durrant@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Ping? > -----Original Message----- > From: Paul Durrant [mailto:paul.durrant@citrix.com] > Sent: 17 February 2016 15:05 > To: xen-devel@lists.xenproject.org > Cc: Paul Durrant; Ian Campbell; Ian Jackson; Jan Beulich; Keir (Xen.org); Tim > (Xen.org) > Subject: [PATCH v4] public/io/netif.h: make control ring hash protocol more > general > > This patch modified the control ring protocol (of which there is > not yet an implementation) to make it more general. Most of the > concepts are not limited to toeplitz hashing so it's best not to > make them unnecessarily specific. > > Apart from changing the names of various definitions and modifying > comments, this patch: > > - Adds a new control message type to select a hash algorithm. > - Adds a reference implementation of the toeplitz hash. > - Changes the 'toeplitz' extra info fragment into a 'hash' extra > info fragment and replaces the octet of padding with the index of > the algorithm that was used to create the hash value. > - Relaxes the restriction that the mapping table has to be > power-of-2 sized. > > The patch also fixes a few spelling typos noticed along the way. > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com> > Cc: Ian Campbell <ian.campbell@citrix.com> > Cc: Ian Jackson <ian.jackson@eu.citrix.com> > Cc: Jan Beulich <jbeulich@suse.com> > Cc: Keir Fraser <keir@xen.org> > Cc: Tim Deegan <tim@xen.org> > --- > > v2: > - Remove 'inline' from reference hash definition and make the > definition optional > > v3: > - Use XEN_NETIF_ prefix instead of NETIF_ > - Make hash mapping table optional > - Allow a hash mapping table that is not power-of-two sized > > v4: > - More NETIF -> XEN_NETIF substitution > - Also defined ctrl message structs with xen_ prefix and get rid > of typedefs > --- > xen/include/public/io/netif.h | 350 +++++++++++++++++++++++++++------- > -------- > 1 file changed, 226 insertions(+), 124 deletions(-) > > diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h > index 8816e0f..ca00614 100644 > --- a/xen/include/public/io/netif.h > +++ b/xen/include/public/io/netif.h > @@ -164,7 +164,7 @@ > * Control ring > * ============ > * > - * Some features, such as toeplitz hashing (detailed below), require a > + * Some features, such as hashing (detailed below), require a > * significant amount of out-of-band data to be passed from frontend to > * backend. Use of xenstore is not suitable for large quantities of data > * because of quota limitations and so a dedicated 'control ring' is used. > @@ -191,8 +191,8 @@ > */ > > /* > - * Toeplitz hash types > - * =================== > + * Hash types > + * ========== > * > * For the purposes of the definitions below, 'Packet[]' is an array of > * octets containing an IP packet without options, 'Array[X..Y]' means a > @@ -206,10 +206,11 @@ > * Buffer[0..8] = Packet[12..15] (source address) + > * Packet[16..19] (destination address) > * > - * Result = ToeplitzHash(Buffer, 8) > + * Result = Hash(Buffer, 8) > */ > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4 0 > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4 (1 << > _NETIF_CTRL_TOEPLITZ_HASH_IPV4) > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4 0 > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4 \ > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4) > > /* > * A hash calculated over an IP version 4 header and TCP header as > @@ -220,10 +221,11 @@ > * Packet[20..21] (source port) + > * Packet[22..23] (destination port) > * > - * Result = ToeplitzHash(Buffer, 12) > + * Result = Hash(Buffer, 12) > */ > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP 1 > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP (1 << > _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP 1 > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP \ > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP) > > /* > * A hash calculated over an IP version 6 header as follows: > @@ -231,10 +233,11 @@ > * Buffer[0..32] = Packet[8..23] (source address ) + > * Packet[24..39] (destination address) > * > - * Result = ToeplitzHash(Buffer, 32) > + * Result = Hash(Buffer, 32) > */ > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6 2 > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6 (1 << > _NETIF_CTRL_TOEPLITZ_HASH_IPV4) > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6 2 > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6 \ > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6) > > /* > * A hash calculated over an IP version 6 header and TCP header as > @@ -245,14 +248,84 @@ > * Packet[40..41] (source port) + > * Packet[42..43] (destination port) > * > - * Result = ToeplitzHash(Buffer, 36) > + * Result = Hash(Buffer, 36) > + */ > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP 3 > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP \ > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP) > + > +/* > + * Hash algorithms > + * =============== > + */ > + > +#define XEN_NETIF_CTRL_HASH_ALGORITHM_NONE 0 > + > +/* > + * Toeplitz hash: > + */ > + > +#define XEN_NETIF_CTRL_HASH_ALGORITHM_TOEPLITZ 1 > + > +/* > + * This algorithm uses a 'key' as well as the data buffer itself. > + * (Buffer[] and Key[] are treated as shift-registers where the MSB of > + * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] > + * is the 'right-most'). > + * > + * Value = 0 > + * For number of bits in Buffer[] > + * If (left-most bit of Buffer[] is 1) > + * Value ^= left-most 32 bits of Key[] > + * Key[] << 1 > + * Buffer[] << 1 > + * > + * The code below is provided for convenience where an operating system > + * does not already provide an implementation. > */ > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP 3 > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP (1 << > _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) > +#ifdef XEN_NETIF_DEFINE_TOEPLITZ > +static uint32_t xen_netif_toeplitz_hash(const uint8_t *key, > + unsigned int keylen, > + const uint8_t *buf, > + unsigned int buflen) > +{ > + unsigned int keyi, bufi; > + uint64_t prefix = 0; > + uint64_t hash = 0; > + > + /* Pre-load prefix with the first 8 bytes of the key */ > + for (keyi = 0; keyi < 8; keyi++) { > + prefix <<= 8; > + prefix |= (keyi < keylen) ? key[keyi] : 0; > + } > + > + for (bufi = 0; bufi < buflen; bufi++) { > + uint8_t byte = buf[bufi]; > + unsigned int bit; > + > + for (bit = 0; bit < 8; bit++) { > + if (byte & 0x80) > + hash ^= prefix; > + prefix <<= 1; > + byte <<=1; > + } > + > + /* > + * 'prefix' has now been left-shifted by 8, so > + * OR in the next byte. > + */ > + prefix |= (keyi < keylen) ? key[keyi] : 0; > + keyi++; > + } > + > + /* The valid part of the hash is in the upper 32 bits. */ > + return hash >> 32; > +} > +#endif /* XEN_NETIF_DEFINE_TOEPLITZ */ > > /* > - * Control requests (netif_ctrl_request_t) > - * ======================================= > + * Control requests (struct xen_netif_ctrl_request) > + * ================================================ > * > * All requests have the following format: > * > @@ -268,25 +341,25 @@ > * data[]: any data associated with the request (determined by type) > */ > > -struct netif_ctrl_request { > +struct xen_netif_ctrl_request { > uint16_t id; > uint16_t type; > > -#define NETIF_CTRL_TYPE_INVALID 0 > -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS 1 > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS 2 > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY 3 > -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER 4 > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER 5 > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING 6 > +#define XEN_NETIF_CTRL_TYPE_INVALID 0 > +#define XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS 1 > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS 2 > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_KEY 3 > +#define XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE 4 > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE 5 > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING 6 > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM 7 > > uint32_t data[3]; > }; > -typedef struct netif_ctrl_request netif_ctrl_request_t; > > /* > - * Control responses (netif_ctrl_response_t) > - * ========================================= > + * Control responses (struct xen_netif_ctrl_response) > + * ================================================== > * > * All responses have the following format: > * > @@ -304,48 +377,74 @@ typedef struct netif_ctrl_request > netif_ctrl_request_t; > * status) > */ > > -struct netif_ctrl_response { > +struct xen_netif_ctrl_response { > uint16_t id; > uint16_t type; > uint32_t status; > > -#define NETIF_CTRL_STATUS_SUCCESS 0 > -#define NETIF_CTRL_STATUS_NOT_SUPPORTED 1 > -#define NETIF_CTRL_STATUS_INVALID_PARAMETER 2 > -#define NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 > +#define XEN_NETIF_CTRL_STATUS_SUCCESS 0 > +#define XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED 1 > +#define XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER 2 > +#define XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 > > uint32_t data; > }; > -typedef struct netif_ctrl_response netif_ctrl_response_t; > > /* > * Control messages > * ================ > * > - * NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS > + * XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM > + * -------------------------------------- > + * > + * This is sent by the frontend to set the desired hash algorithm. > + * > + * Request: > + * > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM > + * data[0] = a XEN_NETIF_CTRL_HASH_ALGORITHM_* value > + * data[1] = 0 > + * data[2] = 0 > + * > + * Response: > + * > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > + * supported > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - The algorithm is > not > + * supported > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * > + * NOTE: Setting data[0] to XEN_NETIF_CTRL_HASH_ALGORITHM_NONE > disables > + * hashing and the backend is free to choose how it steers packets > + * to queues (which is the default behaviour). > + * > + * XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS > * ---------------------------------- > * > - * This is sent by the frontend to query the types of toeplitz > - * hash supported by the backend. > + * This is sent by the frontend to query the types of hash supported by > + * the backend. > * > * Request: > * > - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS > + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS > * data[0] = 0 > * data[1] = 0 > * data[2] = 0 > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > * data = supported hash types (if operation was successful) > * > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS > + * NOTE: A valid hash algorithm must be selected before this operation can > + * succeed. > + * > + * XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS > * ---------------------------------- > * > - * This is sent by the frontend to set the types of toeplitz hash that > - * the backend should calculate. (See above for hash type definitions). > + * This is sent by the frontend to set the types of hash that the backend > + * should calculate. (See above for hash type definitions). > * Note that the 'maximal' type of hash should always be chosen. For > * example, if the frontend sets both IPV4 and IPV4_TCP hash types then > * the latter hash type should be calculated for any TCP packet and the > @@ -353,45 +452,35 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * > * Request: > * > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS > - * data[0] = bitwise OR of NETIF_CTRL_TOEPLITZ_HASH_* values > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS > + * data[0] = bitwise OR of XEN_NETIF_CTRL_HASH_TYPE_* values > * data[1] = 0 > * data[2] = 0 > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag value > - * is invalid or > - * unsupported > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > + * supported > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag > + * value is invalid or > + * unsupported > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > * data = 0 > * > - * NOTE: Setting data[0] to zero disables toeplitz hashing and the backend > - * is free to choose how it steers packets to queues (which is the > - * default behaviour). > + * NOTE: A valid hash algorithm must be selected before this operation can > + * succeed. > + * Also, setting data[0] to zero disables hashing and the backend > + * is free to choose how it steers packets to queues. > * > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY > + * XEN_NETIF_CTRL_TYPE_SET_HASH_KEY > * -------------------------------- > * > - * This is sent by the frontend to set the key of the toeplitz hash that > - * the backend should calculate. The toeplitz algorithm is illustrated > - * by the following pseudo-code: > - * > - * (Buffer[] and Key[] are treated as shift-registers where the MSB of > - * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] > - * is the 'right-most'). > - * > - * Value = 0 > - * For number of bits in Buffer[] > - * If (left-most bit of Buffer[] is 1) > - * Value ^= left-most 32 bits of Key[] > - * Key[] << 1 > - * Buffer[] << 1 > + * This is sent by the frontend to set the key of the hash if the algorithm > + * requires it. (See hash algorithms above). > * > * Request: > * > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_KEY > * data[0] = grant reference of page containing the key (assumed to > * start at beginning of grant) > * data[1] = size of key in octets > @@ -399,11 +488,13 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid > - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger than > - * the backend supports > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > + * supported > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid > + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger > + * than the backend > + * supports > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > * data = 0 > * > * NOTE: Any key octets not specified are assumed to be zero (the key > @@ -411,67 +502,73 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * invalidates any previous key, hence specifying a key size of > * zero will clear the key (which ensures that the calculated hash > * will always be zero). > - * The maximum size of key is backend specific, but is also limited > - * by the single grant reference. > + * The maximum size of key is algorithm and backend specific, but > + * is also limited by the single grant reference. > * The grant reference may be read-only and must remain valid until > * the response has been processed. > * > - * NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER > - * ------------------------------------------ > + * XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE > + * ----------------------------------------- > * > - * This is sent by the frontend to query the maximum order of mapping > - * table supported by the backend. The order is specified in terms of > - * table entries i.e. the table may contain up to 2^order entries. > + * This is sent by the frontend to query the maximum size of mapping > + * table supported by the backend. The size is specified in terms of > + * table entries. > * > * Request: > * > - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER > + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE > * data[0] = 0 > * data[1] = 0 > * data[2] = 0 > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > - * data = maximum order of mapping table (if operation was successful) > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * data = maximum number of entries allowed in the mapping table > + * (if operation was successful) or zero if a mapping table is > + * not supported (i.e. hash mapping is done only by modular > + * arithmetic). > * > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER > - * ------------------------------------------ > + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > + * ------------------------------------- > * > - * This is sent by the frontend to set the actual order of the mapping > - * table to be used by the backend. The order is specified in terms of > - * table entries i.e. the table will contain to 2^order entries. > + * This is sent by the frontend to set the actual size of the mapping > + * table to be used by the backend. The size is specified in terms of > + * table entries. > * Any previous table is invalidated by this message and any new table > - * is assumed to be zero filled. The default order is zero and hence the > - * default table contains a single entry mapping all hashes to queue-0. > + * is assumed to be zero filled. > * > * Request: > * > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER > - * data[0] = order of mapping table > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > + * data[0] = number of entries in mapping table > * data[1] = 0 > * data[2] = 0 > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table order is invalid > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > + * supported > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size is > invalid > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > * data = 0 > * > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING > + * NOTE: Setting data[0] to 0 means that hash mapping should be done > + * using modular arithmetic. > + * > + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING > * ------------------------------------ > * > * This is sent by the frontend to set the content of the table mapping > - * toeplitz hash value to queue number. The backend should calculate the > - * hash from the packet header, use it as an index into the table (modulo > - * the size of the table) and then steer the packet to the queue number > - * found at that index. > + * hash value to queue number. The backend should calculate the hash > from > + * the packet header, use it as an index into the table (modulo the size > + * of the table) and then steer the packet to the queue number found at > + * that index. > * > * Request: > * > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING > * data[0] = grant reference of page containing the mapping (sub-)table > * (assumed to start at beginning of grant) > * data[1] = size of (sub-)table in entries > @@ -479,12 +576,14 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * > * Response: > * > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > supported > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or content is > - * invalid > - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is larger than > - * the backend supports > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > + * supported > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or > content > + * is invalid > + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is > larger > + * than the backend > + * supports > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > * data = 0 > * > * NOTE: The overall table has the following format: > @@ -500,9 +599,8 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * | mapping[N-2] | mapping[N-1] | > * +-----+-----+-----+-----+-----+-----+-----+-----+ > * > - * where N == 2^order as specified by a > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER message and > each > - * mapping must specifies a queue between 0 and > + * where N is specified by a > XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > + * message and each mapping must specifies a queue between 0 and > * "multi-queue-num-queues" (see above). > * The backend may support a mapping table larger than can be > * mapped by a single grant reference. Thus sub-tables within a > @@ -513,7 +611,9 @@ typedef struct netif_ctrl_response > netif_ctrl_response_t; > * the response has been processed. > */ > > -DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct > netif_ctrl_response); > +DEFINE_RING_TYPES(xen_netif_ctrl, > + struct xen_netif_ctrl_request, > + struct xen_netif_ctrl_response); > > /* > * Guest transmit > @@ -531,7 +631,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > netif_ctrl_request, struct netif_ctrl_respo > * ... > * Fragment N: netif_tx_request_t - (only if fragment N-1 flags include > * NETTXF_more_data - flags on preceding > - * extras are not relevent here) > + * extras are not relevant here) > * flags = 0 > * size = fragment size > * > @@ -589,7 +689,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > netif_ctrl_request, struct netif_ctrl_respo > * ... > * Fragment N: netif_rx_request_t - (only if fragment N-1 flags include > * NETRXF_more_data - flags on preceding > - * extras are not relevent here) > + * extras are not relevant here) > * flags = 0 > * size = fragment size > * > @@ -631,7 +731,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > netif_ctrl_request, struct netif_ctrl_respo > * described below, extra info structures overlay the id field). > * Instead it assumes that responses always appear in the same ring > * slot as their corresponding request. Thus, to maintain > - * compatibilty, backends must make sure this is the case. > + * compatibility, backends must make sure this is the case. > * > * Extra Info > * ========== > @@ -696,21 +796,23 @@ DEFINE_RING_TYPES(netif_ctrl, struct > netif_ctrl_request, struct netif_ctrl_respo > * flags: XEN_NETIF_EXTRA_FLAG_* > * addr: address to add/remove > * > - * XEN_NETIF_EXTRA_TYPE_TOEPLITZ: > + * XEN_NETIF_EXTRA_TYPE_HASH: > * > * A backend that supports teoplitz hashing is assumed to accept > * this type of extra info in transmit packets. > - * A frontend that enables toeplitz hashing is assumed to accept > + * A frontend that enables hashing is assumed to accept > * this type of extra info in receive packets. > * > * 0 1 2 3 4 5 6 7 octet > * +-----+-----+-----+-----+-----+-----+-----+-----+ > - * |type |flags|htype| pad |LSB ---- value ---- MSB| > + * |type |flags|htype| alg |LSB ---- value ---- MSB| > * +-----+-----+-----+-----+-----+-----+-----+-----+ > * > - * type: Must be XEN_NETIF_EXTRA_TYPE_TOEPLITZ > + * type: Must be XEN_NETIF_EXTRA_TYPE_HASH > * flags: XEN_NETIF_EXTRA_FLAG_* > - * htype: Hash type (one of _NETIF_CTRL_TOEPLITZ_HASH_* - see above) > + * htype: Hash type (one of _XEN_NETIF_CTRL_HASH_TYPE_* - see above) > + * alg: The algorithm used to calculate the hash (one of > + * XEN_NETIF_CTRL_HASH_TYPE_ALGORITHM_* - see above) > * value: Hash value > */ > > @@ -745,7 +847,7 @@ typedef struct netif_tx_request netif_tx_request_t; > #define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */ > #define XEN_NETIF_EXTRA_TYPE_MCAST_ADD (2) /* u.mcast */ > #define XEN_NETIF_EXTRA_TYPE_MCAST_DEL (3) /* u.mcast */ > -#define XEN_NETIF_EXTRA_TYPE_TOEPLITZ (4) /* u.toeplitz */ > +#define XEN_NETIF_EXTRA_TYPE_HASH (4) /* u.hash */ > #define XEN_NETIF_EXTRA_TYPE_MAX (5) > > /* netif_extra_info_t flags. */ > @@ -776,9 +878,9 @@ struct netif_extra_info { > } mcast; > struct { > uint8_t type; > - uint8_t pad; > + uint8_t algorithm; > uint8_t value[4]; > - } toeplitz; > + } hash; > uint16_t pad[3]; > } u; > }; > -- > 2.1.4
Ping + 1? > -----Original Message----- > From: Paul Durrant > Sent: 22 February 2016 13:06 > To: Paul Durrant; xen-devel@lists.xenproject.org > Cc: Ian Campbell; Ian Jackson; Jan Beulich; Keir (Xen.org); Tim (Xen.org) > Subject: RE: [PATCH v4] public/io/netif.h: make control ring hash protocol > more general > > Ping? > > > -----Original Message----- > > From: Paul Durrant [mailto:paul.durrant@citrix.com] > > Sent: 17 February 2016 15:05 > > To: xen-devel@lists.xenproject.org > > Cc: Paul Durrant; Ian Campbell; Ian Jackson; Jan Beulich; Keir (Xen.org); Tim > > (Xen.org) > > Subject: [PATCH v4] public/io/netif.h: make control ring hash protocol more > > general > > > > This patch modified the control ring protocol (of which there is > > not yet an implementation) to make it more general. Most of the > > concepts are not limited to toeplitz hashing so it's best not to > > make them unnecessarily specific. > > > > Apart from changing the names of various definitions and modifying > > comments, this patch: > > > > - Adds a new control message type to select a hash algorithm. > > - Adds a reference implementation of the toeplitz hash. > > - Changes the 'toeplitz' extra info fragment into a 'hash' extra > > info fragment and replaces the octet of padding with the index of > > the algorithm that was used to create the hash value. > > - Relaxes the restriction that the mapping table has to be > > power-of-2 sized. > > > > The patch also fixes a few spelling typos noticed along the way. > > > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com> > > Cc: Ian Campbell <ian.campbell@citrix.com> > > Cc: Ian Jackson <ian.jackson@eu.citrix.com> > > Cc: Jan Beulich <jbeulich@suse.com> > > Cc: Keir Fraser <keir@xen.org> > > Cc: Tim Deegan <tim@xen.org> > > --- > > > > v2: > > - Remove 'inline' from reference hash definition and make the > > definition optional > > > > v3: > > - Use XEN_NETIF_ prefix instead of NETIF_ > > - Make hash mapping table optional > > - Allow a hash mapping table that is not power-of-two sized > > > > v4: > > - More NETIF -> XEN_NETIF substitution > > - Also defined ctrl message structs with xen_ prefix and get rid > > of typedefs > > --- > > xen/include/public/io/netif.h | 350 +++++++++++++++++++++++++++---- > --- > > -------- > > 1 file changed, 226 insertions(+), 124 deletions(-) > > > > diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h > > index 8816e0f..ca00614 100644 > > --- a/xen/include/public/io/netif.h > > +++ b/xen/include/public/io/netif.h > > @@ -164,7 +164,7 @@ > > * Control ring > > * ============ > > * > > - * Some features, such as toeplitz hashing (detailed below), require a > > + * Some features, such as hashing (detailed below), require a > > * significant amount of out-of-band data to be passed from frontend to > > * backend. Use of xenstore is not suitable for large quantities of data > > * because of quota limitations and so a dedicated 'control ring' is used. > > @@ -191,8 +191,8 @@ > > */ > > > > /* > > - * Toeplitz hash types > > - * =================== > > + * Hash types > > + * ========== > > * > > * For the purposes of the definitions below, 'Packet[]' is an array of > > * octets containing an IP packet without options, 'Array[X..Y]' means a > > @@ -206,10 +206,11 @@ > > * Buffer[0..8] = Packet[12..15] (source address) + > > * Packet[16..19] (destination address) > > * > > - * Result = ToeplitzHash(Buffer, 8) > > + * Result = Hash(Buffer, 8) > > */ > > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4 0 > > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4 (1 << > > _NETIF_CTRL_TOEPLITZ_HASH_IPV4) > > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4 0 > > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4 \ > > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4) > > > > /* > > * A hash calculated over an IP version 4 header and TCP header as > > @@ -220,10 +221,11 @@ > > * Packet[20..21] (source port) + > > * Packet[22..23] (destination port) > > * > > - * Result = ToeplitzHash(Buffer, 12) > > + * Result = Hash(Buffer, 12) > > */ > > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP 1 > > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP (1 << > > _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) > > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP 1 > > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP \ > > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP) > > > > /* > > * A hash calculated over an IP version 6 header as follows: > > @@ -231,10 +233,11 @@ > > * Buffer[0..32] = Packet[8..23] (source address ) + > > * Packet[24..39] (destination address) > > * > > - * Result = ToeplitzHash(Buffer, 32) > > + * Result = Hash(Buffer, 32) > > */ > > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6 2 > > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6 (1 << > > _NETIF_CTRL_TOEPLITZ_HASH_IPV4) > > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6 2 > > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6 \ > > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6) > > > > /* > > * A hash calculated over an IP version 6 header and TCP header as > > @@ -245,14 +248,84 @@ > > * Packet[40..41] (source port) + > > * Packet[42..43] (destination port) > > * > > - * Result = ToeplitzHash(Buffer, 36) > > + * Result = Hash(Buffer, 36) > > + */ > > +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP 3 > > +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP \ > > + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP) > > + > > +/* > > + * Hash algorithms > > + * =============== > > + */ > > + > > +#define XEN_NETIF_CTRL_HASH_ALGORITHM_NONE 0 > > + > > +/* > > + * Toeplitz hash: > > + */ > > + > > +#define XEN_NETIF_CTRL_HASH_ALGORITHM_TOEPLITZ 1 > > + > > +/* > > + * This algorithm uses a 'key' as well as the data buffer itself. > > + * (Buffer[] and Key[] are treated as shift-registers where the MSB of > > + * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] > > + * is the 'right-most'). > > + * > > + * Value = 0 > > + * For number of bits in Buffer[] > > + * If (left-most bit of Buffer[] is 1) > > + * Value ^= left-most 32 bits of Key[] > > + * Key[] << 1 > > + * Buffer[] << 1 > > + * > > + * The code below is provided for convenience where an operating > system > > + * does not already provide an implementation. > > */ > > -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP 3 > > -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP (1 << > > _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) > > +#ifdef XEN_NETIF_DEFINE_TOEPLITZ > > +static uint32_t xen_netif_toeplitz_hash(const uint8_t *key, > > + unsigned int keylen, > > + const uint8_t *buf, > > + unsigned int buflen) > > +{ > > + unsigned int keyi, bufi; > > + uint64_t prefix = 0; > > + uint64_t hash = 0; > > + > > + /* Pre-load prefix with the first 8 bytes of the key */ > > + for (keyi = 0; keyi < 8; keyi++) { > > + prefix <<= 8; > > + prefix |= (keyi < keylen) ? key[keyi] : 0; > > + } > > + > > + for (bufi = 0; bufi < buflen; bufi++) { > > + uint8_t byte = buf[bufi]; > > + unsigned int bit; > > + > > + for (bit = 0; bit < 8; bit++) { > > + if (byte & 0x80) > > + hash ^= prefix; > > + prefix <<= 1; > > + byte <<=1; > > + } > > + > > + /* > > + * 'prefix' has now been left-shifted by 8, so > > + * OR in the next byte. > > + */ > > + prefix |= (keyi < keylen) ? key[keyi] : 0; > > + keyi++; > > + } > > + > > + /* The valid part of the hash is in the upper 32 bits. */ > > + return hash >> 32; > > +} > > +#endif /* XEN_NETIF_DEFINE_TOEPLITZ */ > > > > /* > > - * Control requests (netif_ctrl_request_t) > > - * ======================================= > > + * Control requests (struct xen_netif_ctrl_request) > > + * ================================================ > > * > > * All requests have the following format: > > * > > @@ -268,25 +341,25 @@ > > * data[]: any data associated with the request (determined by type) > > */ > > > > -struct netif_ctrl_request { > > +struct xen_netif_ctrl_request { > > uint16_t id; > > uint16_t type; > > > > -#define NETIF_CTRL_TYPE_INVALID 0 > > -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS 1 > > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS 2 > > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY 3 > > -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER 4 > > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER 5 > > -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING 6 > > +#define XEN_NETIF_CTRL_TYPE_INVALID 0 > > +#define XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS 1 > > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS 2 > > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_KEY 3 > > +#define XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE 4 > > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE 5 > > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING 6 > > +#define XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM 7 > > > > uint32_t data[3]; > > }; > > -typedef struct netif_ctrl_request netif_ctrl_request_t; > > > > /* > > - * Control responses (netif_ctrl_response_t) > > - * ========================================= > > + * Control responses (struct xen_netif_ctrl_response) > > + * ================================================== > > * > > * All responses have the following format: > > * > > @@ -304,48 +377,74 @@ typedef struct netif_ctrl_request > > netif_ctrl_request_t; > > * status) > > */ > > > > -struct netif_ctrl_response { > > +struct xen_netif_ctrl_response { > > uint16_t id; > > uint16_t type; > > uint32_t status; > > > > -#define NETIF_CTRL_STATUS_SUCCESS 0 > > -#define NETIF_CTRL_STATUS_NOT_SUPPORTED 1 > > -#define NETIF_CTRL_STATUS_INVALID_PARAMETER 2 > > -#define NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 > > +#define XEN_NETIF_CTRL_STATUS_SUCCESS 0 > > +#define XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED 1 > > +#define XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER 2 > > +#define XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 > > > > uint32_t data; > > }; > > -typedef struct netif_ctrl_response netif_ctrl_response_t; > > > > /* > > * Control messages > > * ================ > > * > > - * NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS > > + * XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM > > + * -------------------------------------- > > + * > > + * This is sent by the frontend to set the desired hash algorithm. > > + * > > + * Request: > > + * > > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM > > + * data[0] = a XEN_NETIF_CTRL_HASH_ALGORITHM_* value > > + * data[1] = 0 > > + * data[2] = 0 > > + * > > + * Response: > > + * > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - The algorithm > is > > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * > > + * NOTE: Setting data[0] to XEN_NETIF_CTRL_HASH_ALGORITHM_NONE > > disables > > + * hashing and the backend is free to choose how it steers packets > > + * to queues (which is the default behaviour). > > + * > > + * XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS > > * ---------------------------------- > > * > > - * This is sent by the frontend to query the types of toeplitz > > - * hash supported by the backend. > > + * This is sent by the frontend to query the types of hash supported by > > + * the backend. > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS > > + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS > > * data[0] = 0 > > * data[1] = 0 > > * data[2] = 0 > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > * data = supported hash types (if operation was successful) > > * > > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS > > + * NOTE: A valid hash algorithm must be selected before this operation > can > > + * succeed. > > + * > > + * XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS > > * ---------------------------------- > > * > > - * This is sent by the frontend to set the types of toeplitz hash that > > - * the backend should calculate. (See above for hash type definitions). > > + * This is sent by the frontend to set the types of hash that the backend > > + * should calculate. (See above for hash type definitions). > > * Note that the 'maximal' type of hash should always be chosen. For > > * example, if the frontend sets both IPV4 and IPV4_TCP hash types then > > * the latter hash type should be calculated for any TCP packet and the > > @@ -353,45 +452,35 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS > > - * data[0] = bitwise OR of NETIF_CTRL_TOEPLITZ_HASH_* values > > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS > > + * data[0] = bitwise OR of XEN_NETIF_CTRL_HASH_TYPE_* values > > * data[1] = 0 > > * data[2] = 0 > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag > value > > - * is invalid or > > - * unsupported > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more > flag > > + * value is invalid or > > + * unsupported > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > * data = 0 > > * > > - * NOTE: Setting data[0] to zero disables toeplitz hashing and the backend > > - * is free to choose how it steers packets to queues (which is the > > - * default behaviour). > > + * NOTE: A valid hash algorithm must be selected before this operation > can > > + * succeed. > > + * Also, setting data[0] to zero disables hashing and the backend > > + * is free to choose how it steers packets to queues. > > * > > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY > > + * XEN_NETIF_CTRL_TYPE_SET_HASH_KEY > > * -------------------------------- > > * > > - * This is sent by the frontend to set the key of the toeplitz hash that > > - * the backend should calculate. The toeplitz algorithm is illustrated > > - * by the following pseudo-code: > > - * > > - * (Buffer[] and Key[] are treated as shift-registers where the MSB of > > - * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] > > - * is the 'right-most'). > > - * > > - * Value = 0 > > - * For number of bits in Buffer[] > > - * If (left-most bit of Buffer[] is 1) > > - * Value ^= left-most 32 bits of Key[] > > - * Key[] << 1 > > - * Buffer[] << 1 > > + * This is sent by the frontend to set the key of the hash if the algorithm > > + * requires it. (See hash algorithms above). > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY > > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_KEY > > * data[0] = grant reference of page containing the key (assumed to > > * start at beginning of grant) > > * data[1] = size of key in octets > > @@ -399,11 +488,13 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid > > - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger than > > - * the backend supports > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is > invalid > > + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is > larger > > + * than the backend > > + * supports > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > * data = 0 > > * > > * NOTE: Any key octets not specified are assumed to be zero (the key > > @@ -411,67 +502,73 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * invalidates any previous key, hence specifying a key size of > > * zero will clear the key (which ensures that the calculated hash > > * will always be zero). > > - * The maximum size of key is backend specific, but is also limited > > - * by the single grant reference. > > + * The maximum size of key is algorithm and backend specific, but > > + * is also limited by the single grant reference. > > * The grant reference may be read-only and must remain valid until > > * the response has been processed. > > * > > - * NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER > > - * ------------------------------------------ > > + * XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE > > + * ----------------------------------------- > > * > > - * This is sent by the frontend to query the maximum order of mapping > > - * table supported by the backend. The order is specified in terms of > > - * table entries i.e. the table may contain up to 2^order entries. > > + * This is sent by the frontend to query the maximum size of mapping > > + * table supported by the backend. The size is specified in terms of > > + * table entries. > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER > > + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE > > * data[0] = 0 > > * data[1] = 0 > > * data[2] = 0 > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > - * data = maximum order of mapping table (if operation was successful) > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * data = maximum number of entries allowed in the mapping table > > + * (if operation was successful) or zero if a mapping table is > > + * not supported (i.e. hash mapping is done only by modular > > + * arithmetic). > > * > > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER > > - * ------------------------------------------ > > + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > > + * ------------------------------------- > > * > > - * This is sent by the frontend to set the actual order of the mapping > > - * table to be used by the backend. The order is specified in terms of > > - * table entries i.e. the table will contain to 2^order entries. > > + * This is sent by the frontend to set the actual size of the mapping > > + * table to be used by the backend. The size is specified in terms of > > + * table entries. > > * Any previous table is invalidated by this message and any new table > > - * is assumed to be zero filled. The default order is zero and hence the > > - * default table contains a single entry mapping all hashes to queue-0. > > + * is assumed to be zero filled. > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER > > - * data[0] = order of mapping table > > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > > + * data[0] = number of entries in mapping table > > * data[1] = 0 > > * data[2] = 0 > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table order is invalid > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size is > > invalid > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > * data = 0 > > * > > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING > > + * NOTE: Setting data[0] to 0 means that hash mapping should be done > > + * using modular arithmetic. > > + * > > + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING > > * ------------------------------------ > > * > > * This is sent by the frontend to set the content of the table mapping > > - * toeplitz hash value to queue number. The backend should calculate the > > - * hash from the packet header, use it as an index into the table (modulo > > - * the size of the table) and then steer the packet to the queue number > > - * found at that index. > > + * hash value to queue number. The backend should calculate the hash > > from > > + * the packet header, use it as an index into the table (modulo the size > > + * of the table) and then steer the packet to the queue number found at > > + * that index. > > * > > * Request: > > * > > - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING > > + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING > > * data[0] = grant reference of page containing the mapping (sub-)table > > * (assumed to start at beginning of grant) > > * data[1] = size of (sub-)table in entries > > @@ -479,12 +576,14 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * > > * Response: > > * > > - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not > > supported > > - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or content > is > > - * invalid > > - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is larger > than > > - * the backend supports > > - * NETIF_CTRL_STATUS_SUCCESS - Operation successful > > + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation > not > > + * supported > > + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or > > content > > + * is invalid > > + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is > > larger > > + * than the backend > > + * supports > > + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful > > * data = 0 > > * > > * NOTE: The overall table has the following format: > > @@ -500,9 +599,8 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * | mapping[N-2] | mapping[N-1] | > > * +-----+-----+-----+-----+-----+-----+-----+-----+ > > * > > - * where N == 2^order as specified by a > > - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER message and > > each > > - * mapping must specifies a queue between 0 and > > + * where N is specified by a > > XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE > > + * message and each mapping must specifies a queue between 0 and > > * "multi-queue-num-queues" (see above). > > * The backend may support a mapping table larger than can be > > * mapped by a single grant reference. Thus sub-tables within a > > @@ -513,7 +611,9 @@ typedef struct netif_ctrl_response > > netif_ctrl_response_t; > > * the response has been processed. > > */ > > > > -DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct > > netif_ctrl_response); > > +DEFINE_RING_TYPES(xen_netif_ctrl, > > + struct xen_netif_ctrl_request, > > + struct xen_netif_ctrl_response); > > > > /* > > * Guest transmit > > @@ -531,7 +631,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > > netif_ctrl_request, struct netif_ctrl_respo > > * ... > > * Fragment N: netif_tx_request_t - (only if fragment N-1 flags include > > * NETTXF_more_data - flags on preceding > > - * extras are not relevent here) > > + * extras are not relevant here) > > * flags = 0 > > * size = fragment size > > * > > @@ -589,7 +689,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > > netif_ctrl_request, struct netif_ctrl_respo > > * ... > > * Fragment N: netif_rx_request_t - (only if fragment N-1 flags include > > * NETRXF_more_data - flags on preceding > > - * extras are not relevent here) > > + * extras are not relevant here) > > * flags = 0 > > * size = fragment size > > * > > @@ -631,7 +731,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct > > netif_ctrl_request, struct netif_ctrl_respo > > * described below, extra info structures overlay the id field). > > * Instead it assumes that responses always appear in the same ring > > * slot as their corresponding request. Thus, to maintain > > - * compatibilty, backends must make sure this is the case. > > + * compatibility, backends must make sure this is the case. > > * > > * Extra Info > > * ========== > > @@ -696,21 +796,23 @@ DEFINE_RING_TYPES(netif_ctrl, struct > > netif_ctrl_request, struct netif_ctrl_respo > > * flags: XEN_NETIF_EXTRA_FLAG_* > > * addr: address to add/remove > > * > > - * XEN_NETIF_EXTRA_TYPE_TOEPLITZ: > > + * XEN_NETIF_EXTRA_TYPE_HASH: > > * > > * A backend that supports teoplitz hashing is assumed to accept > > * this type of extra info in transmit packets. > > - * A frontend that enables toeplitz hashing is assumed to accept > > + * A frontend that enables hashing is assumed to accept > > * this type of extra info in receive packets. > > * > > * 0 1 2 3 4 5 6 7 octet > > * +-----+-----+-----+-----+-----+-----+-----+-----+ > > - * |type |flags|htype| pad |LSB ---- value ---- MSB| > > + * |type |flags|htype| alg |LSB ---- value ---- MSB| > > * +-----+-----+-----+-----+-----+-----+-----+-----+ > > * > > - * type: Must be XEN_NETIF_EXTRA_TYPE_TOEPLITZ > > + * type: Must be XEN_NETIF_EXTRA_TYPE_HASH > > * flags: XEN_NETIF_EXTRA_FLAG_* > > - * htype: Hash type (one of _NETIF_CTRL_TOEPLITZ_HASH_* - see above) > > + * htype: Hash type (one of _XEN_NETIF_CTRL_HASH_TYPE_* - see > above) > > + * alg: The algorithm used to calculate the hash (one of > > + * XEN_NETIF_CTRL_HASH_TYPE_ALGORITHM_* - see above) > > * value: Hash value > > */ > > > > @@ -745,7 +847,7 @@ typedef struct netif_tx_request > netif_tx_request_t; > > #define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */ > > #define XEN_NETIF_EXTRA_TYPE_MCAST_ADD (2) /* u.mcast */ > > #define XEN_NETIF_EXTRA_TYPE_MCAST_DEL (3) /* u.mcast */ > > -#define XEN_NETIF_EXTRA_TYPE_TOEPLITZ (4) /* u.toeplitz */ > > +#define XEN_NETIF_EXTRA_TYPE_HASH (4) /* u.hash */ > > #define XEN_NETIF_EXTRA_TYPE_MAX (5) > > > > /* netif_extra_info_t flags. */ > > @@ -776,9 +878,9 @@ struct netif_extra_info { > > } mcast; > > struct { > > uint8_t type; > > - uint8_t pad; > > + uint8_t algorithm; > > uint8_t value[4]; > > - } toeplitz; > > + } hash; > > uint16_t pad[3]; > > } u; > > }; > > -- > > 2.1.4
>>> On 26.02.16 at 14:48, <Paul.Durrant@citrix.com> wrote: > Ping + 1? Paul, I guess the primary problem here is that with Ian now unlikely to respond, no-one on the Cc list is likely to jump in. Probably you should resend with the Cc-s extended to the Linux and *BSD netback/netfront maintainers, as they're the most likely ones to have comments here. At least afaic, I'd make an ack dependent on positive feedback from at least one of them. Jan
> -----Original Message----- > From: Jan Beulich [mailto:JBeulich@suse.com] > Sent: 26 February 2016 16:34 > To: Paul Durrant > Cc: Ian Campbell; Ian Jackson; xen-devel@lists.xenproject.org; Keir > (Xen.org); Tim (Xen.org) > Subject: RE: [PATCH v4] public/io/netif.h: make control ring hash protocol > more general > > >>> On 26.02.16 at 14:48, <Paul.Durrant@citrix.com> wrote: > > Ping + 1? > > Paul, > > I guess the primary problem here is that with Ian now unlikely to > respond, no-one on the Cc list is likely to jump in. Probably you > should resend with the Cc-s extended to the Linux and *BSD > netback/netfront maintainers, as they're the most likely ones to > have comments here. At least afaic, I'd make an ack dependent > on positive feedback from at least one of them. > Jan, That's my recollection. I think Wei and David V. would be best placed to give feedback; I'll add them as cc-s. Thanks, Paul > Jan
diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h index 8816e0f..ca00614 100644 --- a/xen/include/public/io/netif.h +++ b/xen/include/public/io/netif.h @@ -164,7 +164,7 @@ * Control ring * ============ * - * Some features, such as toeplitz hashing (detailed below), require a + * Some features, such as hashing (detailed below), require a * significant amount of out-of-band data to be passed from frontend to * backend. Use of xenstore is not suitable for large quantities of data * because of quota limitations and so a dedicated 'control ring' is used. @@ -191,8 +191,8 @@ */ /* - * Toeplitz hash types - * =================== + * Hash types + * ========== * * For the purposes of the definitions below, 'Packet[]' is an array of * octets containing an IP packet without options, 'Array[X..Y]' means a @@ -206,10 +206,11 @@ * Buffer[0..8] = Packet[12..15] (source address) + * Packet[16..19] (destination address) * - * Result = ToeplitzHash(Buffer, 8) + * Result = Hash(Buffer, 8) */ -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4 0 -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4 (1 << _NETIF_CTRL_TOEPLITZ_HASH_IPV4) +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4 0 +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4 \ + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4) /* * A hash calculated over an IP version 4 header and TCP header as @@ -220,10 +221,11 @@ * Packet[20..21] (source port) + * Packet[22..23] (destination port) * - * Result = ToeplitzHash(Buffer, 12) + * Result = Hash(Buffer, 12) */ -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP 1 -#define NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP (1 << _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP 1 +#define XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP \ + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP) /* * A hash calculated over an IP version 6 header as follows: @@ -231,10 +233,11 @@ * Buffer[0..32] = Packet[8..23] (source address ) + * Packet[24..39] (destination address) * - * Result = ToeplitzHash(Buffer, 32) + * Result = Hash(Buffer, 32) */ -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6 2 -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6 (1 << _NETIF_CTRL_TOEPLITZ_HASH_IPV4) +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6 2 +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6 \ + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6) /* * A hash calculated over an IP version 6 header and TCP header as @@ -245,14 +248,84 @@ * Packet[40..41] (source port) + * Packet[42..43] (destination port) * - * Result = ToeplitzHash(Buffer, 36) + * Result = Hash(Buffer, 36) + */ +#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP 3 +#define XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP \ + (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP) + +/* + * Hash algorithms + * =============== + */ + +#define XEN_NETIF_CTRL_HASH_ALGORITHM_NONE 0 + +/* + * Toeplitz hash: + */ + +#define XEN_NETIF_CTRL_HASH_ALGORITHM_TOEPLITZ 1 + +/* + * This algorithm uses a 'key' as well as the data buffer itself. + * (Buffer[] and Key[] are treated as shift-registers where the MSB of + * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] + * is the 'right-most'). + * + * Value = 0 + * For number of bits in Buffer[] + * If (left-most bit of Buffer[] is 1) + * Value ^= left-most 32 bits of Key[] + * Key[] << 1 + * Buffer[] << 1 + * + * The code below is provided for convenience where an operating system + * does not already provide an implementation. */ -#define _NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP 3 -#define NETIF_CTRL_TOEPLITZ_HASH_IPV6_TCP (1 << _NETIF_CTRL_TOEPLITZ_HASH_IPV4_TCP) +#ifdef XEN_NETIF_DEFINE_TOEPLITZ +static uint32_t xen_netif_toeplitz_hash(const uint8_t *key, + unsigned int keylen, + const uint8_t *buf, + unsigned int buflen) +{ + unsigned int keyi, bufi; + uint64_t prefix = 0; + uint64_t hash = 0; + + /* Pre-load prefix with the first 8 bytes of the key */ + for (keyi = 0; keyi < 8; keyi++) { + prefix <<= 8; + prefix |= (keyi < keylen) ? key[keyi] : 0; + } + + for (bufi = 0; bufi < buflen; bufi++) { + uint8_t byte = buf[bufi]; + unsigned int bit; + + for (bit = 0; bit < 8; bit++) { + if (byte & 0x80) + hash ^= prefix; + prefix <<= 1; + byte <<=1; + } + + /* + * 'prefix' has now been left-shifted by 8, so + * OR in the next byte. + */ + prefix |= (keyi < keylen) ? key[keyi] : 0; + keyi++; + } + + /* The valid part of the hash is in the upper 32 bits. */ + return hash >> 32; +} +#endif /* XEN_NETIF_DEFINE_TOEPLITZ */ /* - * Control requests (netif_ctrl_request_t) - * ======================================= + * Control requests (struct xen_netif_ctrl_request) + * ================================================ * * All requests have the following format: * @@ -268,25 +341,25 @@ * data[]: any data associated with the request (determined by type) */ -struct netif_ctrl_request { +struct xen_netif_ctrl_request { uint16_t id; uint16_t type; -#define NETIF_CTRL_TYPE_INVALID 0 -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS 1 -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS 2 -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY 3 -#define NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER 4 -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER 5 -#define NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING 6 +#define XEN_NETIF_CTRL_TYPE_INVALID 0 +#define XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS 1 +#define XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS 2 +#define XEN_NETIF_CTRL_TYPE_SET_HASH_KEY 3 +#define XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE 4 +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE 5 +#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING 6 +#define XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM 7 uint32_t data[3]; }; -typedef struct netif_ctrl_request netif_ctrl_request_t; /* - * Control responses (netif_ctrl_response_t) - * ========================================= + * Control responses (struct xen_netif_ctrl_response) + * ================================================== * * All responses have the following format: * @@ -304,48 +377,74 @@ typedef struct netif_ctrl_request netif_ctrl_request_t; * status) */ -struct netif_ctrl_response { +struct xen_netif_ctrl_response { uint16_t id; uint16_t type; uint32_t status; -#define NETIF_CTRL_STATUS_SUCCESS 0 -#define NETIF_CTRL_STATUS_NOT_SUPPORTED 1 -#define NETIF_CTRL_STATUS_INVALID_PARAMETER 2 -#define NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 +#define XEN_NETIF_CTRL_STATUS_SUCCESS 0 +#define XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED 1 +#define XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER 2 +#define XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3 uint32_t data; }; -typedef struct netif_ctrl_response netif_ctrl_response_t; /* * Control messages * ================ * - * NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS + * XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM + * -------------------------------------- + * + * This is sent by the frontend to set the desired hash algorithm. + * + * Request: + * + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM + * data[0] = a XEN_NETIF_CTRL_HASH_ALGORITHM_* value + * data[1] = 0 + * data[2] = 0 + * + * Response: + * + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not + * supported + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - The algorithm is not + * supported + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful + * + * NOTE: Setting data[0] to XEN_NETIF_CTRL_HASH_ALGORITHM_NONE disables + * hashing and the backend is free to choose how it steers packets + * to queues (which is the default behaviour). + * + * XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS * ---------------------------------- * - * This is sent by the frontend to query the types of toeplitz - * hash supported by the backend. + * This is sent by the frontend to query the types of hash supported by + * the backend. * * Request: * - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_FLAGS + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS * data[0] = 0 * data[1] = 0 * data[2] = 0 * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_SUCCESS - Operation successful + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful * data = supported hash types (if operation was successful) * - * NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS + * NOTE: A valid hash algorithm must be selected before this operation can + * succeed. + * + * XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS * ---------------------------------- * - * This is sent by the frontend to set the types of toeplitz hash that - * the backend should calculate. (See above for hash type definitions). + * This is sent by the frontend to set the types of hash that the backend + * should calculate. (See above for hash type definitions). * Note that the 'maximal' type of hash should always be chosen. For * example, if the frontend sets both IPV4 and IPV4_TCP hash types then * the latter hash type should be calculated for any TCP packet and the @@ -353,45 +452,35 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * * Request: * - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_FLAGS - * data[0] = bitwise OR of NETIF_CTRL_TOEPLITZ_HASH_* values + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS + * data[0] = bitwise OR of XEN_NETIF_CTRL_HASH_TYPE_* values * data[1] = 0 * data[2] = 0 * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag value - * is invalid or - * unsupported - * NETIF_CTRL_STATUS_SUCCESS - Operation successful + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not + * supported + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag + * value is invalid or + * unsupported + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful * data = 0 * - * NOTE: Setting data[0] to zero disables toeplitz hashing and the backend - * is free to choose how it steers packets to queues (which is the - * default behaviour). + * NOTE: A valid hash algorithm must be selected before this operation can + * succeed. + * Also, setting data[0] to zero disables hashing and the backend + * is free to choose how it steers packets to queues. * - * NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY + * XEN_NETIF_CTRL_TYPE_SET_HASH_KEY * -------------------------------- * - * This is sent by the frontend to set the key of the toeplitz hash that - * the backend should calculate. The toeplitz algorithm is illustrated - * by the following pseudo-code: - * - * (Buffer[] and Key[] are treated as shift-registers where the MSB of - * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1] - * is the 'right-most'). - * - * Value = 0 - * For number of bits in Buffer[] - * If (left-most bit of Buffer[] is 1) - * Value ^= left-most 32 bits of Key[] - * Key[] << 1 - * Buffer[] << 1 + * This is sent by the frontend to set the key of the hash if the algorithm + * requires it. (See hash algorithms above). * * Request: * - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_KEY + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_KEY * data[0] = grant reference of page containing the key (assumed to * start at beginning of grant) * data[1] = size of key in octets @@ -399,11 +488,13 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger than - * the backend supports - * NETIF_CTRL_STATUS_SUCCESS - Operation successful + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not + * supported + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger + * than the backend + * supports + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful * data = 0 * * NOTE: Any key octets not specified are assumed to be zero (the key @@ -411,67 +502,73 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * invalidates any previous key, hence specifying a key size of * zero will clear the key (which ensures that the calculated hash * will always be zero). - * The maximum size of key is backend specific, but is also limited - * by the single grant reference. + * The maximum size of key is algorithm and backend specific, but + * is also limited by the single grant reference. * The grant reference may be read-only and must remain valid until * the response has been processed. * - * NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER - * ------------------------------------------ + * XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE + * ----------------------------------------- * - * This is sent by the frontend to query the maximum order of mapping - * table supported by the backend. The order is specified in terms of - * table entries i.e. the table may contain up to 2^order entries. + * This is sent by the frontend to query the maximum size of mapping + * table supported by the backend. The size is specified in terms of + * table entries. * * Request: * - * type = NETIF_CTRL_TYPE_GET_TOEPLITZ_MAPPING_ORDER + * type = XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE * data[0] = 0 * data[1] = 0 * data[2] = 0 * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_SUCCESS - Operation successful - * data = maximum order of mapping table (if operation was successful) + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful + * data = maximum number of entries allowed in the mapping table + * (if operation was successful) or zero if a mapping table is + * not supported (i.e. hash mapping is done only by modular + * arithmetic). * - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER - * ------------------------------------------ + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE + * ------------------------------------- * - * This is sent by the frontend to set the actual order of the mapping - * table to be used by the backend. The order is specified in terms of - * table entries i.e. the table will contain to 2^order entries. + * This is sent by the frontend to set the actual size of the mapping + * table to be used by the backend. The size is specified in terms of + * table entries. * Any previous table is invalidated by this message and any new table - * is assumed to be zero filled. The default order is zero and hence the - * default table contains a single entry mapping all hashes to queue-0. + * is assumed to be zero filled. * * Request: * - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER - * data[0] = order of mapping table + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE + * data[0] = number of entries in mapping table * data[1] = 0 * data[2] = 0 * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table order is invalid - * NETIF_CTRL_STATUS_SUCCESS - Operation successful + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not + * supported + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size is invalid + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful * data = 0 * - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING + * NOTE: Setting data[0] to 0 means that hash mapping should be done + * using modular arithmetic. + * + * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING * ------------------------------------ * * This is sent by the frontend to set the content of the table mapping - * toeplitz hash value to queue number. The backend should calculate the - * hash from the packet header, use it as an index into the table (modulo - * the size of the table) and then steer the packet to the queue number - * found at that index. + * hash value to queue number. The backend should calculate the hash from + * the packet header, use it as an index into the table (modulo the size + * of the table) and then steer the packet to the queue number found at + * that index. * * Request: * - * type = NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING + * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING * data[0] = grant reference of page containing the mapping (sub-)table * (assumed to start at beginning of grant) * data[1] = size of (sub-)table in entries @@ -479,12 +576,14 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * * Response: * - * status = NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported - * NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or content is - * invalid - * NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is larger than - * the backend supports - * NETIF_CTRL_STATUS_SUCCESS - Operation successful + * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not + * supported + * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or content + * is invalid + * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is larger + * than the backend + * supports + * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful * data = 0 * * NOTE: The overall table has the following format: @@ -500,9 +599,8 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * | mapping[N-2] | mapping[N-1] | * +-----+-----+-----+-----+-----+-----+-----+-----+ * - * where N == 2^order as specified by a - * NETIF_CTRL_TYPE_SET_TOEPLITZ_MAPPING_ORDER message and each - * mapping must specifies a queue between 0 and + * where N is specified by a XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE + * message and each mapping must specifies a queue between 0 and * "multi-queue-num-queues" (see above). * The backend may support a mapping table larger than can be * mapped by a single grant reference. Thus sub-tables within a @@ -513,7 +611,9 @@ typedef struct netif_ctrl_response netif_ctrl_response_t; * the response has been processed. */ -DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct netif_ctrl_response); +DEFINE_RING_TYPES(xen_netif_ctrl, + struct xen_netif_ctrl_request, + struct xen_netif_ctrl_response); /* * Guest transmit @@ -531,7 +631,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct netif_ctrl_respo * ... * Fragment N: netif_tx_request_t - (only if fragment N-1 flags include * NETTXF_more_data - flags on preceding - * extras are not relevent here) + * extras are not relevant here) * flags = 0 * size = fragment size * @@ -589,7 +689,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct netif_ctrl_respo * ... * Fragment N: netif_rx_request_t - (only if fragment N-1 flags include * NETRXF_more_data - flags on preceding - * extras are not relevent here) + * extras are not relevant here) * flags = 0 * size = fragment size * @@ -631,7 +731,7 @@ DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct netif_ctrl_respo * described below, extra info structures overlay the id field). * Instead it assumes that responses always appear in the same ring * slot as their corresponding request. Thus, to maintain - * compatibilty, backends must make sure this is the case. + * compatibility, backends must make sure this is the case. * * Extra Info * ========== @@ -696,21 +796,23 @@ DEFINE_RING_TYPES(netif_ctrl, struct netif_ctrl_request, struct netif_ctrl_respo * flags: XEN_NETIF_EXTRA_FLAG_* * addr: address to add/remove * - * XEN_NETIF_EXTRA_TYPE_TOEPLITZ: + * XEN_NETIF_EXTRA_TYPE_HASH: * * A backend that supports teoplitz hashing is assumed to accept * this type of extra info in transmit packets. - * A frontend that enables toeplitz hashing is assumed to accept + * A frontend that enables hashing is assumed to accept * this type of extra info in receive packets. * * 0 1 2 3 4 5 6 7 octet * +-----+-----+-----+-----+-----+-----+-----+-----+ - * |type |flags|htype| pad |LSB ---- value ---- MSB| + * |type |flags|htype| alg |LSB ---- value ---- MSB| * +-----+-----+-----+-----+-----+-----+-----+-----+ * - * type: Must be XEN_NETIF_EXTRA_TYPE_TOEPLITZ + * type: Must be XEN_NETIF_EXTRA_TYPE_HASH * flags: XEN_NETIF_EXTRA_FLAG_* - * htype: Hash type (one of _NETIF_CTRL_TOEPLITZ_HASH_* - see above) + * htype: Hash type (one of _XEN_NETIF_CTRL_HASH_TYPE_* - see above) + * alg: The algorithm used to calculate the hash (one of + * XEN_NETIF_CTRL_HASH_TYPE_ALGORITHM_* - see above) * value: Hash value */ @@ -745,7 +847,7 @@ typedef struct netif_tx_request netif_tx_request_t; #define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */ #define XEN_NETIF_EXTRA_TYPE_MCAST_ADD (2) /* u.mcast */ #define XEN_NETIF_EXTRA_TYPE_MCAST_DEL (3) /* u.mcast */ -#define XEN_NETIF_EXTRA_TYPE_TOEPLITZ (4) /* u.toeplitz */ +#define XEN_NETIF_EXTRA_TYPE_HASH (4) /* u.hash */ #define XEN_NETIF_EXTRA_TYPE_MAX (5) /* netif_extra_info_t flags. */ @@ -776,9 +878,9 @@ struct netif_extra_info { } mcast; struct { uint8_t type; - uint8_t pad; + uint8_t algorithm; uint8_t value[4]; - } toeplitz; + } hash; uint16_t pad[3]; } u; };
This patch modified the control ring protocol (of which there is not yet an implementation) to make it more general. Most of the concepts are not limited to toeplitz hashing so it's best not to make them unnecessarily specific. Apart from changing the names of various definitions and modifying comments, this patch: - Adds a new control message type to select a hash algorithm. - Adds a reference implementation of the toeplitz hash. - Changes the 'toeplitz' extra info fragment into a 'hash' extra info fragment and replaces the octet of padding with the index of the algorithm that was used to create the hash value. - Relaxes the restriction that the mapping table has to be power-of-2 sized. The patch also fixes a few spelling typos noticed along the way. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Ian Jackson <ian.jackson@eu.citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Keir Fraser <keir@xen.org> Cc: Tim Deegan <tim@xen.org> --- v2: - Remove 'inline' from reference hash definition and make the definition optional v3: - Use XEN_NETIF_ prefix instead of NETIF_ - Make hash mapping table optional - Allow a hash mapping table that is not power-of-two sized v4: - More NETIF -> XEN_NETIF substitution - Also defined ctrl message structs with xen_ prefix and get rid of typedefs --- xen/include/public/io/netif.h | 350 +++++++++++++++++++++++++++--------------- 1 file changed, 226 insertions(+), 124 deletions(-)