diff options
| -rw-r--r-- | Documentation/networking/devlink/devlink-region.rst | 8 | ||||
| -rw-r--r-- | include/net/devlink.h | 6 | ||||
| -rw-r--r-- | net/core/devlink.c | 99 |
3 files changed, 113 insertions, 0 deletions
diff --git a/Documentation/networking/devlink/devlink-region.rst b/Documentation/networking/devlink/devlink-region.rst index 8b46e8591fe0..9d2d4c95a5c4 100644 --- a/Documentation/networking/devlink/devlink-region.rst +++ b/Documentation/networking/devlink/devlink-region.rst @@ -20,6 +20,11 @@ address regions that are otherwise inaccessible to the user. Regions may also be used to provide an additional way to debug complex error states, but see also :doc:`devlink-health` +Regions may optionally support capturing a snapshot on demand via the +``DEVLINK_CMD_REGION_NEW`` netlink message. A driver wishing to allow +requested snapshots must implement the ``.snapshot`` callback for the region +in its ``devlink_region_ops`` structure. + example usage ------------- @@ -40,6 +45,9 @@ example usage # Delete a snapshot using: $ devlink region del pci/0000:00:05.0/cr-space snapshot 1 + # Request an immediate snapshot, if supported by the region + $ devlink region new pci/0000:00:05.0/cr-space snapshot 5 + # Dump a snapshot: $ devlink region dump pci/0000:00:05.0/fw-health snapshot 1 0000000000000000 0014 95dc 0014 9514 0035 1670 0034 db30 diff --git a/include/net/devlink.h b/include/net/devlink.h index fb9154060e6e..a1a02cd5890b 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -501,10 +501,16 @@ struct devlink_info_req; * struct devlink_region_ops - Region operations * @name: region name * @destructor: callback used to free snapshot memory when deleting + * @snapshot: callback to request an immediate snapshot. On success, + * the data variable must be updated to point to the snapshot data. + * The function will be called while the devlink instance lock is + * held. */ struct devlink_region_ops { const char *name; void (*destructor)(const void *data); + int (*snapshot)(struct devlink *devlink, struct netlink_ext_ack *extack, + u8 **data); }; struct devlink_fmsg; diff --git a/net/core/devlink.c b/net/core/devlink.c index 76b22593d188..d20efdc8cc73 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -3846,6 +3846,33 @@ static void __devlink_snapshot_id_decrement(struct devlink *devlink, u32 id) } /** + * __devlink_snapshot_id_insert - Insert a specific snapshot ID + * @devlink: devlink instance + * @id: the snapshot id + * + * Mark the given snapshot id as used by inserting a zero value into the + * snapshot xarray. + * + * This must be called while holding the devlink instance lock. Unlike + * devlink_snapshot_id_get, the initial reference count is zero, not one. + * It is expected that the id will immediately be used before + * releasing the devlink instance lock. + * + * Returns zero on success, or an error code if the snapshot id could not + * be inserted. + */ +static int __devlink_snapshot_id_insert(struct devlink *devlink, u32 id) +{ + lockdep_assert_held(&devlink->lock); + + if (WARN_ON(xa_load(&devlink->snapshot_ids, id))) + return -EEXIST; + + return xa_err(xa_store(&devlink->snapshot_ids, id, xa_mk_value(0), + GFP_KERNEL)); +} + +/** * __devlink_region_snapshot_id_get - get snapshot ID * @devlink: devlink instance * @id: storage to return snapshot id @@ -4038,6 +4065,71 @@ static int devlink_nl_cmd_region_del(struct sk_buff *skb, return 0; } +static int +devlink_nl_cmd_region_new(struct sk_buff *skb, struct genl_info *info) +{ + struct devlink *devlink = info->user_ptr[0]; + struct devlink_region *region; + const char *region_name; + u32 snapshot_id; + u8 *data; + int err; + + if (!info->attrs[DEVLINK_ATTR_REGION_NAME]) { + NL_SET_ERR_MSG_MOD(info->extack, "No region name provided"); + return -EINVAL; + } + + if (!info->attrs[DEVLINK_ATTR_REGION_SNAPSHOT_ID]) { + NL_SET_ERR_MSG_MOD(info->extack, "No snapshot id provided"); + return -EINVAL; + } + + region_name = nla_data(info->attrs[DEVLINK_ATTR_REGION_NAME]); + region = devlink_region_get_by_name(devlink, region_name); + if (!region) { + NL_SET_ERR_MSG_MOD(info->extack, "The requested region does not exist"); + return -EINVAL; + } + + if (!region->ops->snapshot) { + NL_SET_ERR_MSG_MOD(info->extack, "The requested region does not support taking an immediate snapshot"); + return -EOPNOTSUPP; + } + + if (region->cur_snapshots == region->max_snapshots) { + NL_SET_ERR_MSG_MOD(info->extack, "The region has reached the maximum number of stored snapshots"); + return -ENOSPC; + } + + snapshot_id = nla_get_u32(info->attrs[DEVLINK_ATTR_REGION_SNAPSHOT_ID]); + + if (devlink_region_snapshot_get_by_id(region, snapshot_id)) { + NL_SET_ERR_MSG_MOD(info->extack, "The requested snapshot id is already in use"); + return -EEXIST; + } + + err = __devlink_snapshot_id_insert(devlink, snapshot_id); + if (err) + return err; + + err = region->ops->snapshot(devlink, info->extack, &data); + if (err) + goto err_snapshot_capture; + + err = __devlink_region_snapshot_create(region, data, snapshot_id); + if (err) + goto err_snapshot_create; + + return 0; + +err_snapshot_create: + region->ops->destructor(data); +err_snapshot_capture: + __devlink_snapshot_id_decrement(devlink, snapshot_id); + return err; +} + static int devlink_nl_cmd_region_read_chunk_fill(struct sk_buff *msg, struct devlink *devlink, u8 *chunk, u32 chunk_size, @@ -6447,6 +6539,13 @@ static const struct genl_ops devlink_nl_ops[] = { .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK, }, { + .cmd = DEVLINK_CMD_REGION_NEW, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = devlink_nl_cmd_region_new, + .flags = GENL_ADMIN_PERM, + .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK, + }, + { .cmd = DEVLINK_CMD_REGION_DEL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = devlink_nl_cmd_region_del, |