diff options
Diffstat (limited to 'include/xen/interface/io')
-rw-r--r-- | include/xen/interface/io/blkif.h | 36 | ||||
-rw-r--r-- | include/xen/interface/io/netif.h | 19 | ||||
-rw-r--r-- | include/xen/interface/io/ring.h | 5 | ||||
-rw-r--r-- | include/xen/interface/io/xs_wire.h | 5 |
4 files changed, 64 insertions, 1 deletions
diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h index 3d5d6db..9324488 100644 --- a/include/xen/interface/io/blkif.h +++ b/include/xen/interface/io/blkif.h @@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t; * "feature-flush-cache" node! */ #define BLKIF_OP_FLUSH_DISKCACHE 3 + +/* + * Recognised only if "feature-discard" is present in backend xenbus info. + * The "feature-discard" node contains a boolean indicating whether trim + * (ATA) or unmap (SCSI) - conviently called discard requests are likely + * to succeed or fail. Either way, a discard request + * may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by + * the underlying block-device hardware. The boolean simply indicates whether + * or not it is worthwhile for the frontend to attempt discard requests. + * If a backend does not recognise BLKIF_OP_DISCARD, it should *not* + * create the "feature-discard" node! + * + * Discard operation is a request for the underlying block device to mark + * extents to be erased. However, discard does not guarantee that the blocks + * will be erased from the device - it is just a hint to the device + * controller that these blocks are no longer in use. What the device + * controller does with that information is left to the controller. + * Discard operations are passed with sector_number as the + * sector index to begin discard operations at and nr_sectors as the number of + * sectors to be discarded. The specified sectors should be discarded if the + * underlying block device supports trim (ATA) or unmap (SCSI) operations, + * or a BLKIF_RSP_EOPNOTSUPP should be returned. + * More information about trim/unmap operations at: + * http://t13.org/Documents/UploadedDocuments/docs2008/ + * e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc + * http://www.seagate.com/staticfiles/support/disc/manuals/ + * Interface%20manuals/100293068c.pdf + */ +#define BLKIF_OP_DISCARD 5 + /* * Maximum scatter/gather segments per request. * This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE. @@ -74,6 +104,11 @@ struct blkif_request_rw { } seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; }; +struct blkif_request_discard { + blkif_sector_t sector_number; + uint64_t nr_sectors; +}; + struct blkif_request { uint8_t operation; /* BLKIF_OP_??? */ uint8_t nr_segments; /* number of segments */ @@ -81,6 +116,7 @@ struct blkif_request { uint64_t id; /* private guest value, echoed in resp */ union { struct blkif_request_rw rw; + struct blkif_request_discard discard; } u; }; diff --git a/include/xen/interface/io/netif.h b/include/xen/interface/io/netif.h index cb94668..d4635cd 100644 --- a/include/xen/interface/io/netif.h +++ b/include/xen/interface/io/netif.h @@ -13,6 +13,24 @@ #include "../grant_table.h" /* + * Older implementation of Xen network frontend / backend has an + * implicit dependency on the MAX_SKB_FRAGS as the maximum number of + * ring slots a skb can use. Netfront / netback may not work as + * expected when frontend and backend have different MAX_SKB_FRAGS. + * + * A better approach is to add mechanism for netfront / netback to + * negotiate this value. However we cannot fix all possible + * frontends, so we need to define a value which states the minimum + * slots backend must support. + * + * The minimum value derives from older Linux kernel's MAX_SKB_FRAGS + * (18), which is proved to work with most frontends. Any new backend + * which doesn't negotiate with frontend should expect frontend to + * send a valid packet using slots up to this value. + */ +#define XEN_NETIF_NR_SLOTS_MIN 18 + +/* * Notifications after enqueuing any type of message should be conditional on * the appropriate req_event or rsp_event field in the shared ring. * If the client sends notification for rx requests then it should specify @@ -47,6 +65,7 @@ #define _XEN_NETTXF_extra_info (3) #define XEN_NETTXF_extra_info (1U<<_XEN_NETTXF_extra_info) +#define XEN_NETIF_MAX_TX_SIZE 0xFFFF struct xen_netif_tx_request { grant_ref_t gref; /* Reference to buffer page */ uint16_t offset; /* Offset within buffer page */ diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h index 75271b9..7d28aff 100644 --- a/include/xen/interface/io/ring.h +++ b/include/xen/interface/io/ring.h @@ -188,6 +188,11 @@ struct __name##_back_ring { \ #define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \ (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r)) +/* Ill-behaved frontend determination: Can there be this many requests? */ +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \ + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r)) + + #define RING_PUSH_REQUESTS(_r) do { \ wmb(); /* back sees requests /before/ updated producer index */ \ (_r)->sring->req_prod = (_r)->req_prod_pvt; \ diff --git a/include/xen/interface/io/xs_wire.h b/include/xen/interface/io/xs_wire.h index 454ee26..7cdfca2 100644 --- a/include/xen/interface/io/xs_wire.h +++ b/include/xen/interface/io/xs_wire.h @@ -26,7 +26,10 @@ enum xsd_sockmsg_type XS_SET_PERMS, XS_WATCH_EVENT, XS_ERROR, - XS_IS_DOMAIN_INTRODUCED + XS_IS_DOMAIN_INTRODUCED, + XS_RESUME, + XS_SET_TARGET, + XS_RESTRICT }; #define XS_WRITE_NONE "NONE" |