diff options
Diffstat (limited to 'net/devlink/region.c')
| -rw-r--r-- | net/devlink/region.c | 1260 |
1 files changed, 1260 insertions, 0 deletions
diff --git a/net/devlink/region.c b/net/devlink/region.c new file mode 100644 index 0000000000..d197cdb662 --- /dev/null +++ b/net/devlink/region.c @@ -0,0 +1,1260 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2016 Mellanox Technologies. All rights reserved. + * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com> + */ + +#include "devl_internal.h" + +struct devlink_region { + struct devlink *devlink; + struct devlink_port *port; + struct list_head list; + union { + const struct devlink_region_ops *ops; + const struct devlink_port_region_ops *port_ops; + }; + struct mutex snapshot_lock; /* protects snapshot_list, + * max_snapshots and cur_snapshots + * consistency. + */ + struct list_head snapshot_list; + u32 max_snapshots; + u32 cur_snapshots; + u64 size; +}; + +struct devlink_snapshot { + struct list_head list; + struct devlink_region *region; + u8 *data; + u32 id; +}; + +static struct devlink_region * +devlink_region_get_by_name(struct devlink *devlink, const char *region_name) +{ + struct devlink_region *region; + + list_for_each_entry(region, &devlink->region_list, list) + if (!strcmp(region->ops->name, region_name)) + return region; + + return NULL; +} + +static struct devlink_region * +devlink_port_region_get_by_name(struct devlink_port *port, + const char *region_name) +{ + struct devlink_region *region; + + list_for_each_entry(region, &port->region_list, list) + if (!strcmp(region->ops->name, region_name)) + return region; + + return NULL; +} + +static struct devlink_snapshot * +devlink_region_snapshot_get_by_id(struct devlink_region *region, u32 id) +{ + struct devlink_snapshot *snapshot; + + list_for_each_entry(snapshot, ®ion->snapshot_list, list) + if (snapshot->id == id) + return snapshot; + + return NULL; +} + +static int devlink_nl_region_snapshot_id_put(struct sk_buff *msg, + struct devlink *devlink, + struct devlink_snapshot *snapshot) +{ + struct nlattr *snap_attr; + int err; + + snap_attr = nla_nest_start_noflag(msg, DEVLINK_ATTR_REGION_SNAPSHOT); + if (!snap_attr) + return -EINVAL; + + err = nla_put_u32(msg, DEVLINK_ATTR_REGION_SNAPSHOT_ID, snapshot->id); + if (err) + goto nla_put_failure; + + nla_nest_end(msg, snap_attr); + return 0; + +nla_put_failure: + nla_nest_cancel(msg, snap_attr); + return err; +} + +static int devlink_nl_region_snapshots_id_put(struct sk_buff *msg, + struct devlink *devlink, + struct devlink_region *region) +{ + struct devlink_snapshot *snapshot; + struct nlattr *snapshots_attr; + int err; + + snapshots_attr = nla_nest_start_noflag(msg, + DEVLINK_ATTR_REGION_SNAPSHOTS); + if (!snapshots_attr) + return -EINVAL; + + list_for_each_entry(snapshot, ®ion->snapshot_list, list) { + err = devlink_nl_region_snapshot_id_put(msg, devlink, snapshot); + if (err) + goto nla_put_failure; + } + + nla_nest_end(msg, snapshots_attr); + return 0; + +nla_put_failure: + nla_nest_cancel(msg, snapshots_attr); + return err; +} + +static int devlink_nl_region_fill(struct sk_buff *msg, struct devlink *devlink, + enum devlink_command cmd, u32 portid, + u32 seq, int flags, + struct devlink_region *region) +{ + void *hdr; + int err; + + hdr = genlmsg_put(msg, portid, seq, &devlink_nl_family, flags, cmd); + if (!hdr) + return -EMSGSIZE; + + err = devlink_nl_put_handle(msg, devlink); + if (err) + goto nla_put_failure; + + if (region->port) { + err = nla_put_u32(msg, DEVLINK_ATTR_PORT_INDEX, + region->port->index); + if (err) + goto nla_put_failure; + } + + err = nla_put_string(msg, DEVLINK_ATTR_REGION_NAME, region->ops->name); + if (err) + goto nla_put_failure; + + err = nla_put_u64_64bit(msg, DEVLINK_ATTR_REGION_SIZE, + region->size, + DEVLINK_ATTR_PAD); + if (err) + goto nla_put_failure; + + err = nla_put_u32(msg, DEVLINK_ATTR_REGION_MAX_SNAPSHOTS, + region->max_snapshots); + if (err) + goto nla_put_failure; + + err = devlink_nl_region_snapshots_id_put(msg, devlink, region); + if (err) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return err; +} + +static struct sk_buff * +devlink_nl_region_notify_build(struct devlink_region *region, + struct devlink_snapshot *snapshot, + enum devlink_command cmd, u32 portid, u32 seq) +{ + struct devlink *devlink = region->devlink; + struct sk_buff *msg; + void *hdr; + int err; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return ERR_PTR(-ENOMEM); + + hdr = genlmsg_put(msg, portid, seq, &devlink_nl_family, 0, cmd); + if (!hdr) { + err = -EMSGSIZE; + goto out_free_msg; + } + + err = devlink_nl_put_handle(msg, devlink); + if (err) + goto out_cancel_msg; + + if (region->port) { + err = nla_put_u32(msg, DEVLINK_ATTR_PORT_INDEX, + region->port->index); + if (err) + goto out_cancel_msg; + } + + err = nla_put_string(msg, DEVLINK_ATTR_REGION_NAME, + region->ops->name); + if (err) + goto out_cancel_msg; + + if (snapshot) { + err = nla_put_u32(msg, DEVLINK_ATTR_REGION_SNAPSHOT_ID, + snapshot->id); + if (err) + goto out_cancel_msg; + } else { + err = nla_put_u64_64bit(msg, DEVLINK_ATTR_REGION_SIZE, + region->size, DEVLINK_ATTR_PAD); + if (err) + goto out_cancel_msg; + } + genlmsg_end(msg, hdr); + + return msg; + +out_cancel_msg: + genlmsg_cancel(msg, hdr); +out_free_msg: + nlmsg_free(msg); + return ERR_PTR(err); +} + +static void devlink_nl_region_notify(struct devlink_region *region, + struct devlink_snapshot *snapshot, + enum devlink_command cmd) +{ + struct devlink *devlink = region->devlink; + struct sk_buff *msg; + + WARN_ON(cmd != DEVLINK_CMD_REGION_NEW && cmd != DEVLINK_CMD_REGION_DEL); + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED)) + return; + + msg = devlink_nl_region_notify_build(region, snapshot, cmd, 0, 0); + if (IS_ERR(msg)) + return; + + genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg, + 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL); +} + +void devlink_regions_notify_register(struct devlink *devlink) +{ + struct devlink_region *region; + + list_for_each_entry(region, &devlink->region_list, list) + devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_NEW); +} + +void devlink_regions_notify_unregister(struct devlink *devlink) +{ + struct devlink_region *region; + + list_for_each_entry_reverse(region, &devlink->region_list, list) + devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_DEL); +} + +/** + * __devlink_snapshot_id_increment - Increment number of snapshots using an id + * @devlink: devlink instance + * @id: the snapshot id + * + * Track when a new snapshot begins using an id. Load the count for the + * given id from the snapshot xarray, increment it, and store it back. + * + * Called when a new snapshot is created with the given id. + * + * The id *must* have been previously allocated by + * devlink_region_snapshot_id_get(). + * + * Returns 0 on success, or an error on failure. + */ +static int __devlink_snapshot_id_increment(struct devlink *devlink, u32 id) +{ + unsigned long count; + void *p; + int err; + + xa_lock(&devlink->snapshot_ids); + p = xa_load(&devlink->snapshot_ids, id); + if (WARN_ON(!p)) { + err = -EINVAL; + goto unlock; + } + + if (WARN_ON(!xa_is_value(p))) { + err = -EINVAL; + goto unlock; + } + + count = xa_to_value(p); + count++; + + err = xa_err(__xa_store(&devlink->snapshot_ids, id, xa_mk_value(count), + GFP_ATOMIC)); +unlock: + xa_unlock(&devlink->snapshot_ids); + return err; +} + +/** + * __devlink_snapshot_id_decrement - Decrease number of snapshots using an id + * @devlink: devlink instance + * @id: the snapshot id + * + * Track when a snapshot is deleted and stops using an id. Load the count + * for the given id from the snapshot xarray, decrement it, and store it + * back. + * + * If the count reaches zero, erase this id from the xarray, freeing it + * up for future re-use by devlink_region_snapshot_id_get(). + * + * Called when a snapshot using the given id is deleted, and when the + * initial allocator of the id is finished using it. + */ +static void __devlink_snapshot_id_decrement(struct devlink *devlink, u32 id) +{ + unsigned long count; + void *p; + + xa_lock(&devlink->snapshot_ids); + p = xa_load(&devlink->snapshot_ids, id); + if (WARN_ON(!p)) + goto unlock; + + if (WARN_ON(!xa_is_value(p))) + goto unlock; + + count = xa_to_value(p); + + if (count > 1) { + count--; + __xa_store(&devlink->snapshot_ids, id, xa_mk_value(count), + GFP_ATOMIC); + } else { + /* If this was the last user, we can erase this id */ + __xa_erase(&devlink->snapshot_ids, id); + } +unlock: + xa_unlock(&devlink->snapshot_ids); +} + +/** + * __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) +{ + int err; + + xa_lock(&devlink->snapshot_ids); + if (xa_load(&devlink->snapshot_ids, id)) { + xa_unlock(&devlink->snapshot_ids); + return -EEXIST; + } + err = xa_err(__xa_store(&devlink->snapshot_ids, id, xa_mk_value(0), + GFP_ATOMIC)); + xa_unlock(&devlink->snapshot_ids); + return err; +} + +/** + * __devlink_region_snapshot_id_get - get snapshot ID + * @devlink: devlink instance + * @id: storage to return snapshot id + * + * Allocates a new snapshot id. Returns zero on success, or a negative + * error on failure. Must be called while holding the devlink instance + * lock. + * + * Snapshot IDs are tracked using an xarray which stores the number of + * users of the snapshot id. + * + * Note that the caller of this function counts as a 'user', in order to + * avoid race conditions. The caller must release its hold on the + * snapshot by using devlink_region_snapshot_id_put. + */ +static int __devlink_region_snapshot_id_get(struct devlink *devlink, u32 *id) +{ + return xa_alloc(&devlink->snapshot_ids, id, xa_mk_value(1), + xa_limit_32b, GFP_KERNEL); +} + +/** + * __devlink_region_snapshot_create - create a new snapshot + * This will add a new snapshot of a region. The snapshot + * will be stored on the region struct and can be accessed + * from devlink. This is useful for future analyses of snapshots. + * Multiple snapshots can be created on a region. + * The @snapshot_id should be obtained using the getter function. + * + * Must be called only while holding the region snapshot lock. + * + * @region: devlink region of the snapshot + * @data: snapshot data + * @snapshot_id: snapshot id to be created + */ +static int +__devlink_region_snapshot_create(struct devlink_region *region, + u8 *data, u32 snapshot_id) +{ + struct devlink *devlink = region->devlink; + struct devlink_snapshot *snapshot; + int err; + + lockdep_assert_held(®ion->snapshot_lock); + + /* check if region can hold one more snapshot */ + if (region->cur_snapshots == region->max_snapshots) + return -ENOSPC; + + if (devlink_region_snapshot_get_by_id(region, snapshot_id)) + return -EEXIST; + + snapshot = kzalloc(sizeof(*snapshot), GFP_KERNEL); + if (!snapshot) + return -ENOMEM; + + err = __devlink_snapshot_id_increment(devlink, snapshot_id); + if (err) + goto err_snapshot_id_increment; + + snapshot->id = snapshot_id; + snapshot->region = region; + snapshot->data = data; + + list_add_tail(&snapshot->list, ®ion->snapshot_list); + + region->cur_snapshots++; + + devlink_nl_region_notify(region, snapshot, DEVLINK_CMD_REGION_NEW); + return 0; + +err_snapshot_id_increment: + kfree(snapshot); + return err; +} + +static void devlink_region_snapshot_del(struct devlink_region *region, + struct devlink_snapshot *snapshot) +{ + struct devlink *devlink = region->devlink; + + lockdep_assert_held(®ion->snapshot_lock); + + devlink_nl_region_notify(region, snapshot, DEVLINK_CMD_REGION_DEL); + region->cur_snapshots--; + list_del(&snapshot->list); + region->ops->destructor(snapshot->data); + __devlink_snapshot_id_decrement(devlink, snapshot->id); + kfree(snapshot); +} + +int devlink_nl_region_get_doit(struct sk_buff *skb, struct genl_info *info) +{ + struct devlink *devlink = info->user_ptr[0]; + struct devlink_port *port = NULL; + struct devlink_region *region; + const char *region_name; + struct sk_buff *msg; + unsigned int index; + int err; + + if (GENL_REQ_ATTR_CHECK(info, DEVLINK_ATTR_REGION_NAME)) + return -EINVAL; + + if (info->attrs[DEVLINK_ATTR_PORT_INDEX]) { + index = nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_INDEX]); + + port = devlink_port_get_by_index(devlink, index); + if (!port) + return -ENODEV; + } + + region_name = nla_data(info->attrs[DEVLINK_ATTR_REGION_NAME]); + if (port) + region = devlink_port_region_get_by_name(port, region_name); + else + region = devlink_region_get_by_name(devlink, region_name); + + if (!region) + return -EINVAL; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + err = devlink_nl_region_fill(msg, devlink, DEVLINK_CMD_REGION_GET, + info->snd_portid, info->snd_seq, 0, + region); + if (err) { + nlmsg_free(msg); + return err; + } + + return genlmsg_reply(msg, info); +} + +static int devlink_nl_cmd_region_get_port_dumpit(struct sk_buff *msg, + struct netlink_callback *cb, + struct devlink_port *port, + int *idx, int start, int flags) +{ + struct devlink_region *region; + int err = 0; + + list_for_each_entry(region, &port->region_list, list) { + if (*idx < start) { + (*idx)++; + continue; + } + err = devlink_nl_region_fill(msg, port->devlink, + DEVLINK_CMD_REGION_GET, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, + flags, region); + if (err) + goto out; + (*idx)++; + } + +out: + return err; +} + +static int devlink_nl_region_get_dump_one(struct sk_buff *msg, + struct devlink *devlink, + struct netlink_callback *cb, + int flags) +{ + struct devlink_nl_dump_state *state = devlink_dump_state(cb); + struct devlink_region *region; + struct devlink_port *port; + unsigned long port_index; + int idx = 0; + int err; + + list_for_each_entry(region, &devlink->region_list, list) { + if (idx < state->idx) { + idx++; + continue; + } + err = devlink_nl_region_fill(msg, devlink, + DEVLINK_CMD_REGION_GET, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, flags, + region); + if (err) { + state->idx = idx; + return err; + } + idx++; + } + + xa_for_each(&devlink->ports, port_index, port) { + err = devlink_nl_cmd_region_get_port_dumpit(msg, cb, port, &idx, + state->idx, flags); + if (err) { + state->idx = idx; + return err; + } + } + + return 0; +} + +int devlink_nl_region_get_dumpit(struct sk_buff *skb, + struct netlink_callback *cb) +{ + return devlink_nl_dumpit(skb, cb, devlink_nl_region_get_dump_one); +} + +int devlink_nl_cmd_region_del(struct sk_buff *skb, struct genl_info *info) +{ + struct devlink *devlink = info->user_ptr[0]; + struct devlink_snapshot *snapshot; + struct devlink_port *port = NULL; + struct devlink_region *region; + const char *region_name; + unsigned int index; + u32 snapshot_id; + + if (GENL_REQ_ATTR_CHECK(info, DEVLINK_ATTR_REGION_NAME) || + GENL_REQ_ATTR_CHECK(info, DEVLINK_ATTR_REGION_SNAPSHOT_ID)) + return -EINVAL; + + region_name = nla_data(info->attrs[DEVLINK_ATTR_REGION_NAME]); + snapshot_id = nla_get_u32(info->attrs[DEVLINK_ATTR_REGION_SNAPSHOT_ID]); + + if (info->attrs[DEVLINK_ATTR_PORT_INDEX]) { + index = nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_INDEX]); + + port = devlink_port_get_by_index(devlink, index); + if (!port) + return -ENODEV; + } + + if (port) + region = devlink_port_region_get_by_name(port, region_name); + else + region = devlink_region_get_by_name(devlink, region_name); + + if (!region) + return -EINVAL; + + mutex_lock(®ion->snapshot_lock); + snapshot = devlink_region_snapshot_get_by_id(region, snapshot_id); + if (!snapshot) { + mutex_unlock(®ion->snapshot_lock); + return -EINVAL; + } + + devlink_region_snapshot_del(region, snapshot); + mutex_unlock(®ion->snapshot_lock); + return 0; +} + +int devlink_nl_cmd_region_new(struct sk_buff *skb, struct genl_info *info) +{ + struct devlink *devlink = info->user_ptr[0]; + struct devlink_snapshot *snapshot; + struct devlink_port *port = NULL; + struct nlattr *snapshot_id_attr; + struct devlink_region *region; + const char *region_name; + unsigned int index; + u32 snapshot_id; + u8 *data; + int err; + + if (GENL_REQ_ATTR_CHECK(info, DEVLINK_ATTR_REGION_NAME)) { + NL_SET_ERR_MSG(info->extack, "No region name provided"); + return -EINVAL; + } + + region_name = nla_data(info->attrs[DEVLINK_ATTR_REGION_NAME]); + + if (info->attrs[DEVLINK_ATTR_PORT_INDEX]) { + index = nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_INDEX]); + + port = devlink_port_get_by_index(devlink, index); + if (!port) + return -ENODEV; + } + + if (port) + region = devlink_port_region_get_by_name(port, region_name); + else + region = devlink_region_get_by_name(devlink, region_name); + + if (!region) { + NL_SET_ERR_MSG(info->extack, "The requested region does not exist"); + return -EINVAL; + } + + if (!region->ops->snapshot) { + NL_SET_ERR_MSG(info->extack, "The requested region does not support taking an immediate snapshot"); + return -EOPNOTSUPP; + } + + mutex_lock(®ion->snapshot_lock); + + if (region->cur_snapshots == region->max_snapshots) { + NL_SET_ERR_MSG(info->extack, "The region has reached the maximum number of stored snapshots"); + err = -ENOSPC; + goto unlock; + } + + snapshot_id_attr = info->attrs[DEVLINK_ATTR_REGION_SNAPSHOT_ID]; + if (snapshot_id_attr) { + snapshot_id = nla_get_u32(snapshot_id_attr); + + if (devlink_region_snapshot_get_by_id(region, snapshot_id)) { + NL_SET_ERR_MSG(info->extack, "The requested snapshot id is already in use"); + err = -EEXIST; + goto unlock; + } + + err = __devlink_snapshot_id_insert(devlink, snapshot_id); + if (err) + goto unlock; + } else { + err = __devlink_region_snapshot_id_get(devlink, &snapshot_id); + if (err) { + NL_SET_ERR_MSG(info->extack, "Failed to allocate a new snapshot id"); + goto unlock; + } + } + + if (port) + err = region->port_ops->snapshot(port, region->port_ops, + info->extack, &data); + else + err = region->ops->snapshot(devlink, region->ops, + info->extack, &data); + if (err) + goto err_snapshot_capture; + + err = __devlink_region_snapshot_create(region, data, snapshot_id); + if (err) + goto err_snapshot_create; + + if (!snapshot_id_attr) { + struct sk_buff *msg; + + snapshot = devlink_region_snapshot_get_by_id(region, + snapshot_id); + if (WARN_ON(!snapshot)) { + err = -EINVAL; + goto unlock; + } + + msg = devlink_nl_region_notify_build(region, snapshot, + DEVLINK_CMD_REGION_NEW, + info->snd_portid, + info->snd_seq); + err = PTR_ERR_OR_ZERO(msg); + if (err) + goto err_notify; + + err = genlmsg_reply(msg, info); + if (err) + goto err_notify; + } + + mutex_unlock(®ion->snapshot_lock); + return 0; + +err_snapshot_create: + region->ops->destructor(data); +err_snapshot_capture: + __devlink_snapshot_id_decrement(devlink, snapshot_id); + mutex_unlock(®ion->snapshot_lock); + return err; + +err_notify: + devlink_region_snapshot_del(region, snapshot); +unlock: + mutex_unlock(®ion->snapshot_lock); + return err; +} + +static int devlink_nl_cmd_region_read_chunk_fill(struct sk_buff *msg, + u8 *chunk, u32 chunk_size, + u64 addr) +{ + struct nlattr *chunk_attr; + int err; + + chunk_attr = nla_nest_start_noflag(msg, DEVLINK_ATTR_REGION_CHUNK); + if (!chunk_attr) + return -EINVAL; + + err = nla_put(msg, DEVLINK_ATTR_REGION_CHUNK_DATA, chunk_size, chunk); + if (err) + goto nla_put_failure; + + err = nla_put_u64_64bit(msg, DEVLINK_ATTR_REGION_CHUNK_ADDR, addr, + DEVLINK_ATTR_PAD); + if (err) + goto nla_put_failure; + + nla_nest_end(msg, chunk_attr); + return 0; + +nla_put_failure: + nla_nest_cancel(msg, chunk_attr); + return err; +} + +#define DEVLINK_REGION_READ_CHUNK_SIZE 256 + +typedef int devlink_chunk_fill_t(void *cb_priv, u8 *chunk, u32 chunk_size, + u64 curr_offset, + struct netlink_ext_ack *extack); + +static int +devlink_nl_region_read_fill(struct sk_buff *skb, devlink_chunk_fill_t *cb, + void *cb_priv, u64 start_offset, u64 end_offset, + u64 *new_offset, struct netlink_ext_ack *extack) +{ + u64 curr_offset = start_offset; + int err = 0; + u8 *data; + + /* Allocate and re-use a single buffer */ + data = kmalloc(DEVLINK_REGION_READ_CHUNK_SIZE, GFP_KERNEL); + if (!data) + return -ENOMEM; + + *new_offset = start_offset; + + while (curr_offset < end_offset) { + u32 data_size; + + data_size = min_t(u32, end_offset - curr_offset, + DEVLINK_REGION_READ_CHUNK_SIZE); + + err = cb(cb_priv, data, data_size, curr_offset, extack); + if (err) + break; + + err = devlink_nl_cmd_region_read_chunk_fill(skb, data, data_size, curr_offset); + if (err) + break; + + curr_offset += data_size; + } + *new_offset = curr_offset; + + kfree(data); + + return err; +} + +static int +devlink_region_snapshot_fill(void *cb_priv, u8 *chunk, u32 chunk_size, + u64 curr_offset, + struct netlink_ext_ack __always_unused *extack) +{ + struct devlink_snapshot *snapshot = cb_priv; + + memcpy(chunk, &snapshot->data[curr_offset], chunk_size); + + return 0; +} + +static int +devlink_region_port_direct_fill(void *cb_priv, u8 *chunk, u32 chunk_size, + u64 curr_offset, struct netlink_ext_ack *extack) +{ + struct devlink_region *region = cb_priv; + + return region->port_ops->read(region->port, region->port_ops, extack, + curr_offset, chunk_size, chunk); +} + +static int +devlink_region_direct_fill(void *cb_priv, u8 *chunk, u32 chunk_size, + u64 curr_offset, struct netlink_ext_ack *extack) +{ + struct devlink_region *region = cb_priv; + + return region->ops->read(region->devlink, region->ops, extack, + curr_offset, chunk_size, chunk); +} + +int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb, + struct netlink_callback *cb) +{ + const struct genl_dumpit_info *info = genl_dumpit_info(cb); + struct devlink_nl_dump_state *state = devlink_dump_state(cb); + struct nlattr *chunks_attr, *region_attr, *snapshot_attr; + u64 ret_offset, start_offset, end_offset = U64_MAX; + struct nlattr **attrs = info->info.attrs; + struct devlink_port *port = NULL; + devlink_chunk_fill_t *region_cb; + struct devlink_region *region; + const char *region_name; + struct devlink *devlink; + unsigned int index; + void *region_cb_priv; + void *hdr; + int err; + + start_offset = state->start_offset; + + devlink = devlink_get_from_attrs_lock(sock_net(cb->skb->sk), attrs); + if (IS_ERR(devlink)) + return PTR_ERR(devlink); + + if (!attrs[DEVLINK_ATTR_REGION_NAME]) { + NL_SET_ERR_MSG(cb->extack, "No region name provided"); + err = -EINVAL; + goto out_unlock; + } + + if (attrs[DEVLINK_ATTR_PORT_INDEX]) { + index = nla_get_u32(attrs[DEVLINK_ATTR_PORT_INDEX]); + + port = devlink_port_get_by_index(devlink, index); + if (!port) { + err = -ENODEV; + goto out_unlock; + } + } + + region_attr = attrs[DEVLINK_ATTR_REGION_NAME]; + region_name = nla_data(region_attr); + + if (port) + region = devlink_port_region_get_by_name(port, region_name); + else + region = devlink_region_get_by_name(devlink, region_name); + + if (!region) { + NL_SET_ERR_MSG_ATTR(cb->extack, region_attr, "Requested region does not exist"); + err = -EINVAL; + goto out_unlock; + } + + snapshot_attr = attrs[DEVLINK_ATTR_REGION_SNAPSHOT_ID]; + if (!snapshot_attr) { + if (!nla_get_flag(attrs[DEVLINK_ATTR_REGION_DIRECT])) { + NL_SET_ERR_MSG(cb->extack, "No snapshot id provided"); + err = -EINVAL; + goto out_unlock; + } + + if (!region->ops->read) { + NL_SET_ERR_MSG(cb->extack, "Requested region does not support direct read"); + err = -EOPNOTSUPP; + goto out_unlock; + } + + if (port) + region_cb = &devlink_region_port_direct_fill; + else + region_cb = &devlink_region_direct_fill; + region_cb_priv = region; + } else { + struct devlink_snapshot *snapshot; + u32 snapshot_id; + + if (nla_get_flag(attrs[DEVLINK_ATTR_REGION_DIRECT])) { + NL_SET_ERR_MSG_ATTR(cb->extack, snapshot_attr, "Direct region read does not use snapshot"); + err = -EINVAL; + goto out_unlock; + } + + snapshot_id = nla_get_u32(snapshot_attr); + snapshot = devlink_region_snapshot_get_by_id(region, snapshot_id); + if (!snapshot) { + NL_SET_ERR_MSG_ATTR(cb->extack, snapshot_attr, "Requested snapshot does not exist"); + err = -EINVAL; + goto out_unlock; + } + region_cb = &devlink_region_snapshot_fill; + region_cb_priv = snapshot; + } + + if (attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR] && + attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]) { + if (!start_offset) + start_offset = + nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]); + + end_offset = nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_ADDR]); + end_offset += nla_get_u64(attrs[DEVLINK_ATTR_REGION_CHUNK_LEN]); + } + + if (end_offset > region->size) + end_offset = region->size; + + /* return 0 if there is no further data to read */ + if (start_offset == end_offset) { + err = 0; + goto out_unlock; + } + + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &devlink_nl_family, NLM_F_ACK | NLM_F_MULTI, + DEVLINK_CMD_REGION_READ); + if (!hdr) { + err = -EMSGSIZE; + goto out_unlock; + } + + err = devlink_nl_put_handle(skb, devlink); + if (err) + goto nla_put_failure; + + if (region->port) { + err = nla_put_u32(skb, DEVLINK_ATTR_PORT_INDEX, + region->port->index); + if (err) + goto nla_put_failure; + } + + err = nla_put_string(skb, DEVLINK_ATTR_REGION_NAME, region_name); + if (err) + goto nla_put_failure; + + chunks_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_REGION_CHUNKS); + if (!chunks_attr) { + err = -EMSGSIZE; + goto nla_put_failure; + } + + err = devlink_nl_region_read_fill(skb, region_cb, region_cb_priv, + start_offset, end_offset, &ret_offset, + cb->extack); + + if (err && err != -EMSGSIZE) + goto nla_put_failure; + + /* Check if there was any progress done to prevent infinite loop */ + if (ret_offset == start_offset) { + err = -EINVAL; + goto nla_put_failure; + } + + state->start_offset = ret_offset; + + nla_nest_end(skb, chunks_attr); + genlmsg_end(skb, hdr); + devl_unlock(devlink); + devlink_put(devlink); + return skb->len; + +nla_put_failure: + genlmsg_cancel(skb, hdr); +out_unlock: + devl_unlock(devlink); + devlink_put(devlink); + return err; +} + +/** + * devl_region_create - create a new address region + * + * @devlink: devlink + * @ops: region operations and name + * @region_max_snapshots: Maximum supported number of snapshots for region + * @region_size: size of region + */ +struct devlink_region *devl_region_create(struct devlink *devlink, + const struct devlink_region_ops *ops, + u32 region_max_snapshots, + u64 region_size) +{ + struct devlink_region *region; + + devl_assert_locked(devlink); + + if (WARN_ON(!ops) || WARN_ON(!ops->destructor)) + return ERR_PTR(-EINVAL); + + if (devlink_region_get_by_name(devlink, ops->name)) + return ERR_PTR(-EEXIST); + + region = kzalloc(sizeof(*region), GFP_KERNEL); + if (!region) + return ERR_PTR(-ENOMEM); + + region->devlink = devlink; + region->max_snapshots = region_max_snapshots; + region->ops = ops; + region->size = region_size; + INIT_LIST_HEAD(®ion->snapshot_list); + mutex_init(®ion->snapshot_lock); + list_add_tail(®ion->list, &devlink->region_list); + devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_NEW); + + return region; +} +EXPORT_SYMBOL_GPL(devl_region_create); + +/** + * devlink_region_create - create a new address region + * + * @devlink: devlink + * @ops: region operations and name + * @region_max_snapshots: Maximum supported number of snapshots for region + * @region_size: size of region + * + * Context: Takes and release devlink->lock <mutex>. + */ +struct devlink_region * +devlink_region_create(struct devlink *devlink, + const struct devlink_region_ops *ops, + u32 region_max_snapshots, u64 region_size) +{ + struct devlink_region *region; + + devl_lock(devlink); + region = devl_region_create(devlink, ops, region_max_snapshots, + region_size); + devl_unlock(devlink); + return region; +} +EXPORT_SYMBOL_GPL(devlink_region_create); + +/** + * devlink_port_region_create - create a new address region for a port + * + * @port: devlink port + * @ops: region operations and name + * @region_max_snapshots: Maximum supported number of snapshots for region + * @region_size: size of region + * + * Context: Takes and release devlink->lock <mutex>. + */ +struct devlink_region * +devlink_port_region_create(struct devlink_port *port, + const struct devlink_port_region_ops *ops, + u32 region_max_snapshots, u64 region_size) +{ + struct devlink *devlink = port->devlink; + struct devlink_region *region; + int err = 0; + + ASSERT_DEVLINK_PORT_INITIALIZED(port); + + if (WARN_ON(!ops) || WARN_ON(!ops->destructor)) + return ERR_PTR(-EINVAL); + + devl_lock(devlink); + + if (devlink_port_region_get_by_name(port, ops->name)) { + err = -EEXIST; + goto unlock; + } + + region = kzalloc(sizeof(*region), GFP_KERNEL); + if (!region) { + err = -ENOMEM; + goto unlock; + } + + region->devlink = devlink; + region->port = port; + region->max_snapshots = region_max_snapshots; + region->port_ops = ops; + region->size = region_size; + INIT_LIST_HEAD(®ion->snapshot_list); + mutex_init(®ion->snapshot_lock); + list_add_tail(®ion->list, &port->region_list); + devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_NEW); + + devl_unlock(devlink); + return region; + +unlock: + devl_unlock(devlink); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(devlink_port_region_create); + +/** + * devl_region_destroy - destroy address region + * + * @region: devlink region to destroy + */ +void devl_region_destroy(struct devlink_region *region) +{ + struct devlink *devlink = region->devlink; + struct devlink_snapshot *snapshot, *ts; + + devl_assert_locked(devlink); + + /* Free all snapshots of region */ + mutex_lock(®ion->snapshot_lock); + list_for_each_entry_safe(snapshot, ts, ®ion->snapshot_list, list) + devlink_region_snapshot_del(region, snapshot); + mutex_unlock(®ion->snapshot_lock); + + list_del(®ion->list); + mutex_destroy(®ion->snapshot_lock); + + devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_DEL); + kfree(region); +} +EXPORT_SYMBOL_GPL(devl_region_destroy); + +/** + * devlink_region_destroy - destroy address region + * + * @region: devlink region to destroy + * + * Context: Takes and release devlink->lock <mutex>. + */ +void devlink_region_destroy(struct devlink_region *region) +{ + struct devlink *devlink = region->devlink; + + devl_lock(devlink); + devl_region_destroy(region); + devl_unlock(devlink); +} +EXPORT_SYMBOL_GPL(devlink_region_destroy); + +/** + * devlink_region_snapshot_id_get - get snapshot ID + * + * This callback should be called when adding a new snapshot, + * Driver should use the same id for multiple snapshots taken + * on multiple regions at the same time/by the same trigger. + * + * The caller of this function must use devlink_region_snapshot_id_put + * when finished creating regions using this id. + * + * Returns zero on success, or a negative error code on failure. + * + * @devlink: devlink + * @id: storage to return id + */ +int devlink_region_snapshot_id_get(struct devlink *devlink, u32 *id) +{ + return __devlink_region_snapshot_id_get(devlink, id); +} +EXPORT_SYMBOL_GPL(devlink_region_snapshot_id_get); + +/** + * devlink_region_snapshot_id_put - put snapshot ID reference + * + * This should be called by a driver after finishing creating snapshots + * with an id. Doing so ensures that the ID can later be released in the + * event that all snapshots using it have been destroyed. + * + * @devlink: devlink + * @id: id to release reference on + */ +void devlink_region_snapshot_id_put(struct devlink *devlink, u32 id) +{ + __devlink_snapshot_id_decrement(devlink, id); +} +EXPORT_SYMBOL_GPL(devlink_region_snapshot_id_put); + +/** + * devlink_region_snapshot_create - create a new snapshot + * This will add a new snapshot of a region. The snapshot + * will be stored on the region struct and can be accessed + * from devlink. This is useful for future analyses of snapshots. + * Multiple snapshots can be created on a region. + * The @snapshot_id should be obtained using the getter function. + * + * @region: devlink region of the snapshot + * @data: snapshot data + * @snapshot_id: snapshot id to be created + */ +int devlink_region_snapshot_create(struct devlink_region *region, + u8 *data, u32 snapshot_id) +{ + int err; + + mutex_lock(®ion->snapshot_lock); + err = __devlink_region_snapshot_create(region, data, snapshot_id); + mutex_unlock(®ion->snapshot_lock); + return err; +} +EXPORT_SYMBOL_GPL(devlink_region_snapshot_create); |