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tools: Sync uapi bpf.h header with latest changes 

Synchronize the header after all of the recent changes.

Signed-off-by: Joe Stringer <joe@cilium.io>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210302171947.2268128-16-joe@cilium.io
This commit is contained in:
Joe Stringer 2021-03-02 09:19:47 -08:00 committed by Alexei Starovoitov
parent 6197e5b7b1
commit 242029f426
1 changed files with 711 additions and 1 deletions
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712
tools/include/uapi/linux/bpf.h
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@ -93,7 +93,717 @@ union bpf_iter_link_info {
} map; } map;
}; };
/* BPF syscall commands, see bpf(2) man-page for details. */ /* BPF syscall commands, see bpf(2) man-page for more details. */
/**
* DOC: eBPF Syscall Preamble
*
* The operation to be performed by the **bpf**\ () system call is determined
* by the *cmd* argument. Each operation takes an accompanying argument,
* provided via *attr*, which is a pointer to a union of type *bpf_attr* (see
* below). The size argument is the size of the union pointed to by *attr*.
*/
/**
* DOC: eBPF Syscall Commands
*
* BPF_MAP_CREATE
* Description
* Create a map and return a file descriptor that refers to the
* map. The close-on-exec file descriptor flag (see **fcntl**\ (2))
* is automatically enabled for the new file descriptor.
*
* Applying **close**\ (2) to the file descriptor returned by
* **BPF_MAP_CREATE** will delete the map (but see NOTES).
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_MAP_LOOKUP_ELEM
* Description
* Look up an element with a given *key* in the map referred to
* by the file descriptor *map_fd*.
*
* The *flags* argument may be specified as one of the
* following:
*
* **BPF_F_LOCK**
* Look up the value of a spin-locked map without
* returning the lock. This must be specified if the
* elements contain a spinlock.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_MAP_UPDATE_ELEM
* Description
* Create or update an element (key/value pair) in a specified map.
*
* The *flags* argument should be specified as one of the
* following:
*
* **BPF_ANY**
* Create a new element or update an existing element.
* **BPF_NOEXIST**
* Create a new element only if it did not exist.
* **BPF_EXIST**
* Update an existing element.
* **BPF_F_LOCK**
* Update a spin_lock-ed map element.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* May set *errno* to **EINVAL**, **EPERM**, **ENOMEM**,
* **E2BIG**, **EEXIST**, or **ENOENT**.
*
* **E2BIG**
* The number of elements in the map reached the
* *max_entries* limit specified at map creation time.
* **EEXIST**
* If *flags* specifies **BPF_NOEXIST** and the element
* with *key* already exists in the map.
* **ENOENT**
* If *flags* specifies **BPF_EXIST** and the element with
* *key* does not exist in the map.
*
* BPF_MAP_DELETE_ELEM
* Description
* Look up and delete an element by key in a specified map.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_MAP_GET_NEXT_KEY
* Description
* Look up an element by key in a specified map and return the key
* of the next element. Can be used to iterate over all elements
* in the map.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* The following cases can be used to iterate over all elements of
* the map:
*
* * If *key* is not found, the operation returns zero and sets
* the *next_key* pointer to the key of the first element.
* * If *key* is found, the operation returns zero and sets the
* *next_key* pointer to the key of the next element.
* * If *key* is the last element, returns -1 and *errno* is set
* to **ENOENT**.
*
* May set *errno* to **ENOMEM**, **EFAULT**, **EPERM**, or
* **EINVAL** on error.
*
* BPF_PROG_LOAD
* Description
* Verify and load an eBPF program, returning a new file
* descriptor associated with the program.
*
* Applying **close**\ (2) to the file descriptor returned by
* **BPF_PROG_LOAD** will unload the eBPF program (but see NOTES).
*
* The close-on-exec file descriptor flag (see **fcntl**\ (2)) is
* automatically enabled for the new file descriptor.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_OBJ_PIN
* Description
* Pin an eBPF program or map referred by the specified *bpf_fd*
* to the provided *pathname* on the filesystem.
*
* The *pathname* argument must not contain a dot (".").
*
* On success, *pathname* retains a reference to the eBPF object,
* preventing deallocation of the object when the original
* *bpf_fd* is closed. This allow the eBPF object to live beyond
* **close**\ (\ *bpf_fd*\ ), and hence the lifetime of the parent
* process.
*
* Applying **unlink**\ (2) or similar calls to the *pathname*
* unpins the object from the filesystem, removing the reference.
* If no other file descriptors or filesystem nodes refer to the
* same object, it will be deallocated (see NOTES).
*
* The filesystem type for the parent directory of *pathname* must
* be **BPF_FS_MAGIC**.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_OBJ_GET
* Description
* Open a file descriptor for the eBPF object pinned to the
* specified *pathname*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_PROG_ATTACH
* Description
* Attach an eBPF program to a *target_fd* at the specified
* *attach_type* hook.
*
* The *attach_type* specifies the eBPF attachment point to
* attach the program to, and must be one of *bpf_attach_type*
* (see below).
*
* The *attach_bpf_fd* must be a valid file descriptor for a
* loaded eBPF program of a cgroup, flow dissector, LIRC, sockmap
* or sock_ops type corresponding to the specified *attach_type*.
*
* The *target_fd* must be a valid file descriptor for a kernel
* object which depends on the attach type of *attach_bpf_fd*:
*
* **BPF_PROG_TYPE_CGROUP_DEVICE**,
* **BPF_PROG_TYPE_CGROUP_SKB**,
* **BPF_PROG_TYPE_CGROUP_SOCK**,
* **BPF_PROG_TYPE_CGROUP_SOCK_ADDR**,
* **BPF_PROG_TYPE_CGROUP_SOCKOPT**,
* **BPF_PROG_TYPE_CGROUP_SYSCTL**,
* **BPF_PROG_TYPE_SOCK_OPS**
*
* Control Group v2 hierarchy with the eBPF controller
* enabled. Requires the kernel to be compiled with
* **CONFIG_CGROUP_BPF**.
*
* **BPF_PROG_TYPE_FLOW_DISSECTOR**
*
* Network namespace (eg /proc/self/ns/net).
*
* **BPF_PROG_TYPE_LIRC_MODE2**
*
* LIRC device path (eg /dev/lircN). Requires the kernel
* to be compiled with **CONFIG_BPF_LIRC_MODE2**.
*
* **BPF_PROG_TYPE_SK_SKB**,
* **BPF_PROG_TYPE_SK_MSG**
*
* eBPF map of socket type (eg **BPF_MAP_TYPE_SOCKHASH**).
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_PROG_DETACH
* Description
* Detach the eBPF program associated with the *target_fd* at the
* hook specified by *attach_type*. The program must have been
* previously attached using **BPF_PROG_ATTACH**.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_PROG_TEST_RUN
* Description
* Run the eBPF program associated with the *prog_fd* a *repeat*
* number of times against a provided program context *ctx_in* and
* data *data_in*, and return the modified program context
* *ctx_out*, *data_out* (for example, packet data), result of the
* execution *retval*, and *duration* of the test run.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* **ENOSPC**
* Either *data_size_out* or *ctx_size_out* is too small.
* **ENOTSUPP**
* This command is not supported by the program type of
* the program referred to by *prog_fd*.
*
* BPF_PROG_GET_NEXT_ID
* Description
* Fetch the next eBPF program currently loaded into the kernel.
*
* Looks for the eBPF program with an id greater than *start_id*
* and updates *next_id* on success. If no other eBPF programs
* remain with ids higher than *start_id*, returns -1 and sets
* *errno* to **ENOENT**.
*
* Return
* Returns zero on success. On error, or when no id remains, -1
* is returned and *errno* is set appropriately.
*
* BPF_MAP_GET_NEXT_ID
* Description
* Fetch the next eBPF map currently loaded into the kernel.
*
* Looks for the eBPF map with an id greater than *start_id*
* and updates *next_id* on success. If no other eBPF maps
* remain with ids higher than *start_id*, returns -1 and sets
* *errno* to **ENOENT**.
*
* Return
* Returns zero on success. On error, or when no id remains, -1
* is returned and *errno* is set appropriately.
*
* BPF_PROG_GET_FD_BY_ID
* Description
* Open a file descriptor for the eBPF program corresponding to
* *prog_id*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_MAP_GET_FD_BY_ID
* Description
* Open a file descriptor for the eBPF map corresponding to
* *map_id*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_OBJ_GET_INFO_BY_FD
* Description
* Obtain information about the eBPF object corresponding to
* *bpf_fd*.
*
* Populates up to *info_len* bytes of *info*, which will be in
* one of the following formats depending on the eBPF object type
* of *bpf_fd*:
*
* * **struct bpf_prog_info**
* * **struct bpf_map_info**
* * **struct bpf_btf_info**
* * **struct bpf_link_info**
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_PROG_QUERY
* Description
* Obtain information about eBPF programs associated with the
* specified *attach_type* hook.
*
* The *target_fd* must be a valid file descriptor for a kernel
* object which depends on the attach type of *attach_bpf_fd*:
*
* **BPF_PROG_TYPE_CGROUP_DEVICE**,
* **BPF_PROG_TYPE_CGROUP_SKB**,
* **BPF_PROG_TYPE_CGROUP_SOCK**,
* **BPF_PROG_TYPE_CGROUP_SOCK_ADDR**,
* **BPF_PROG_TYPE_CGROUP_SOCKOPT**,
* **BPF_PROG_TYPE_CGROUP_SYSCTL**,
* **BPF_PROG_TYPE_SOCK_OPS**
*
* Control Group v2 hierarchy with the eBPF controller
* enabled. Requires the kernel to be compiled with
* **CONFIG_CGROUP_BPF**.
*
* **BPF_PROG_TYPE_FLOW_DISSECTOR**
*
* Network namespace (eg /proc/self/ns/net).
*
* **BPF_PROG_TYPE_LIRC_MODE2**
*
* LIRC device path (eg /dev/lircN). Requires the kernel
* to be compiled with **CONFIG_BPF_LIRC_MODE2**.
*
* **BPF_PROG_QUERY** always fetches the number of programs
* attached and the *attach_flags* which were used to attach those
* programs. Additionally, if *prog_ids* is nonzero and the number
* of attached programs is less than *prog_cnt*, populates
* *prog_ids* with the eBPF program ids of the programs attached
* at *target_fd*.
*
* The following flags may alter the result:
*
* **BPF_F_QUERY_EFFECTIVE**
* Only return information regarding programs which are
* currently effective at the specified *target_fd*.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_RAW_TRACEPOINT_OPEN
* Description
* Attach an eBPF program to a tracepoint *name* to access kernel
* internal arguments of the tracepoint in their raw form.
*
* The *prog_fd* must be a valid file descriptor associated with
* a loaded eBPF program of type **BPF_PROG_TYPE_RAW_TRACEPOINT**.
*
* No ABI guarantees are made about the content of tracepoint
* arguments exposed to the corresponding eBPF program.
*
* Applying **close**\ (2) to the file descriptor returned by
* **BPF_RAW_TRACEPOINT_OPEN** will delete the map (but see NOTES).
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_BTF_LOAD
* Description
* Verify and load BPF Type Format (BTF) metadata into the kernel,
* returning a new file descriptor associated with the metadata.
* BTF is described in more detail at
* https://www.kernel.org/doc/html/latest/bpf/btf.html.
*
* The *btf* parameter must point to valid memory providing
* *btf_size* bytes of BTF binary metadata.
*
* The returned file descriptor can be passed to other **bpf**\ ()
* subcommands such as **BPF_PROG_LOAD** or **BPF_MAP_CREATE** to
* associate the BTF with those objects.
*
* Similar to **BPF_PROG_LOAD**, **BPF_BTF_LOAD** has optional
* parameters to specify a *btf_log_buf*, *btf_log_size* and
* *btf_log_level* which allow the kernel to return freeform log
* output regarding the BTF verification process.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_BTF_GET_FD_BY_ID
* Description
* Open a file descriptor for the BPF Type Format (BTF)
* corresponding to *btf_id*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_TASK_FD_QUERY
* Description
* Obtain information about eBPF programs associated with the
* target process identified by *pid* and *fd*.
*
* If the *pid* and *fd* are associated with a tracepoint, kprobe
* or uprobe perf event, then the *prog_id* and *fd_type* will
* be populated with the eBPF program id and file descriptor type
* of type **bpf_task_fd_type**. If associated with a kprobe or
* uprobe, the *probe_offset* and *probe_addr* will also be
* populated. Optionally, if *buf* is provided, then up to
* *buf_len* bytes of *buf* will be populated with the name of
* the tracepoint, kprobe or uprobe.
*
* The resulting *prog_id* may be introspected in deeper detail
* using **BPF_PROG_GET_FD_BY_ID** and **BPF_OBJ_GET_INFO_BY_FD**.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_MAP_LOOKUP_AND_DELETE_ELEM
* Description
* Look up an element with the given *key* in the map referred to
* by the file descriptor *fd*, and if found, delete the element.
*
* The **BPF_MAP_TYPE_QUEUE** and **BPF_MAP_TYPE_STACK** map types
* implement this command as a "pop" operation, deleting the top
* element rather than one corresponding to *key*.
* The *key* and *key_len* parameters should be zeroed when
* issuing this operation for these map types.
*
* This command is only valid for the following map types:
* * **BPF_MAP_TYPE_QUEUE**
* * **BPF_MAP_TYPE_STACK**
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_MAP_FREEZE
* Description
* Freeze the permissions of the specified map.
*
* Write permissions may be frozen by passing zero *flags*.
* Upon success, no future syscall invocations may alter the
* map state of *map_fd*. Write operations from eBPF programs
* are still possible for a frozen map.
*
* Not supported for maps of type **BPF_MAP_TYPE_STRUCT_OPS**.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_BTF_GET_NEXT_ID
* Description
* Fetch the next BPF Type Format (BTF) object currently loaded
* into the kernel.
*
* Looks for the BTF object with an id greater than *start_id*
* and updates *next_id* on success. If no other BTF objects
* remain with ids higher than *start_id*, returns -1 and sets
* *errno* to **ENOENT**.
*
* Return
* Returns zero on success. On error, or when no id remains, -1
* is returned and *errno* is set appropriately.
*
* BPF_MAP_LOOKUP_BATCH
* Description
* Iterate and fetch multiple elements in a map.
*
* Two opaque values are used to manage batch operations,
* *in_batch* and *out_batch*. Initially, *in_batch* must be set
* to NULL to begin the batched operation. After each subsequent
* **BPF_MAP_LOOKUP_BATCH**, the caller should pass the resultant
* *out_batch* as the *in_batch* for the next operation to
* continue iteration from the current point.
*
* The *keys* and *values* are output parameters which must point
* to memory large enough to hold *count* items based on the key
* and value size of the map *map_fd*. The *keys* buffer must be
* of *key_size* * *count*. The *values* buffer must be of
* *value_size* * *count*.
*
* The *elem_flags* argument may be specified as one of the
* following:
*
* **BPF_F_LOCK**
* Look up the value of a spin-locked map without
* returning the lock. This must be specified if the
* elements contain a spinlock.
*
* On success, *count* elements from the map are copied into the
* user buffer, with the keys copied into *keys* and the values
* copied into the corresponding indices in *values*.
*
* If an error is returned and *errno* is not **EFAULT**, *count*
* is set to the number of successfully processed elements.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* May set *errno* to **ENOSPC** to indicate that *keys* or
* *values* is too small to dump an entire bucket during
* iteration of a hash-based map type.
*
* BPF_MAP_LOOKUP_AND_DELETE_BATCH
* Description
* Iterate and delete all elements in a map.
*
* This operation has the same behavior as
* **BPF_MAP_LOOKUP_BATCH** with two exceptions:
*
* * Every element that is successfully returned is also deleted
* from the map. This is at least *count* elements. Note that
* *count* is both an input and an output parameter.
* * Upon returning with *errno* set to **EFAULT**, up to
* *count* elements may be deleted without returning the keys
* and values of the deleted elements.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_MAP_UPDATE_BATCH
* Description
* Update multiple elements in a map by *key*.
*
* The *keys* and *values* are input parameters which must point
* to memory large enough to hold *count* items based on the key
* and value size of the map *map_fd*. The *keys* buffer must be
* of *key_size* * *count*. The *values* buffer must be of
* *value_size* * *count*.
*
* Each element specified in *keys* is sequentially updated to the
* value in the corresponding index in *values*. The *in_batch*
* and *out_batch* parameters are ignored and should be zeroed.
*
* The *elem_flags* argument should be specified as one of the
* following:
*
* **BPF_ANY**
* Create new elements or update a existing elements.
* **BPF_NOEXIST**
* Create new elements only if they do not exist.
* **BPF_EXIST**
* Update existing elements.
* **BPF_F_LOCK**
* Update spin_lock-ed map elements. This must be
* specified if the map value contains a spinlock.
*
* On success, *count* elements from the map are updated.
*
* If an error is returned and *errno* is not **EFAULT**, *count*
* is set to the number of successfully processed elements.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* May set *errno* to **EINVAL**, **EPERM**, **ENOMEM**, or
* **E2BIG**. **E2BIG** indicates that the number of elements in
* the map reached the *max_entries* limit specified at map
* creation time.
*
* May set *errno* to one of the following error codes under
* specific circumstances:
*
* **EEXIST**
* If *flags* specifies **BPF_NOEXIST** and the element
* with *key* already exists in the map.
* **ENOENT**
* If *flags* specifies **BPF_EXIST** and the element with
* *key* does not exist in the map.
*
* BPF_MAP_DELETE_BATCH
* Description
* Delete multiple elements in a map by *key*.
*
* The *keys* parameter is an input parameter which must point
* to memory large enough to hold *count* items based on the key
* size of the map *map_fd*, that is, *key_size* * *count*.
*
* Each element specified in *keys* is sequentially deleted. The
* *in_batch*, *out_batch*, and *values* parameters are ignored
* and should be zeroed.
*
* The *elem_flags* argument may be specified as one of the
* following:
*
* **BPF_F_LOCK**
* Look up the value of a spin-locked map without
* returning the lock. This must be specified if the
* elements contain a spinlock.
*
* On success, *count* elements from the map are updated.
*
* If an error is returned and *errno* is not **EFAULT**, *count*
* is set to the number of successfully processed elements. If
* *errno* is **EFAULT**, up to *count* elements may be been
* deleted.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_LINK_CREATE
* Description
* Attach an eBPF program to a *target_fd* at the specified
* *attach_type* hook and return a file descriptor handle for
* managing the link.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_LINK_UPDATE
* Description
* Update the eBPF program in the specified *link_fd* to
* *new_prog_fd*.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_LINK_GET_FD_BY_ID
* Description
* Open a file descriptor for the eBPF Link corresponding to
* *link_id*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_LINK_GET_NEXT_ID
* Description
* Fetch the next eBPF link currently loaded into the kernel.
*
* Looks for the eBPF link with an id greater than *start_id*
* and updates *next_id* on success. If no other eBPF links
* remain with ids higher than *start_id*, returns -1 and sets
* *errno* to **ENOENT**.
*
* Return
* Returns zero on success. On error, or when no id remains, -1
* is returned and *errno* is set appropriately.
*
* BPF_ENABLE_STATS
* Description
* Enable eBPF runtime statistics gathering.
*
* Runtime statistics gathering for the eBPF runtime is disabled
* by default to minimize the corresponding performance overhead.
* This command enables statistics globally.
*
* Multiple programs may independently enable statistics.
* After gathering the desired statistics, eBPF runtime statistics
* may be disabled again by calling **close**\ (2) for the file
* descriptor returned by this function. Statistics will only be
* disabled system-wide when all outstanding file descriptors
* returned by prior calls for this subcommand are closed.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_ITER_CREATE
* Description
* Create an iterator on top of the specified *link_fd* (as
* previously created using **BPF_LINK_CREATE**) and return a
* file descriptor that can be used to trigger the iteration.
*
* If the resulting file descriptor is pinned to the filesystem
* using **BPF_OBJ_PIN**, then subsequent **read**\ (2) syscalls
* for that path will trigger the iterator to read kernel state
* using the eBPF program attached to *link_fd*.
*
* Return
* A new file descriptor (a nonnegative integer), or -1 if an
* error occurred (in which case, *errno* is set appropriately).
*
* BPF_LINK_DETACH
* Description
* Forcefully detach the specified *link_fd* from its
* corresponding attachment point.
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* BPF_PROG_BIND_MAP
* Description
* Bind a map to the lifetime of an eBPF program.
*
* The map identified by *map_fd* is bound to the program
* identified by *prog_fd* and only released when *prog_fd* is
* released. This may be used in cases where metadata should be
* associated with a program which otherwise does not contain any
* references to the map (for example, embedded in the eBPF
* program instructions).
*
* Return
* Returns zero on success. On error, -1 is returned and *errno*
* is set appropriately.
*
* NOTES
* eBPF objects (maps and programs) can be shared between processes.
*
* * After **fork**\ (2), the child inherits file descriptors
* referring to the same eBPF objects.
* * File descriptors referring to eBPF objects can be transferred over
* **unix**\ (7) domain sockets.
* * File descriptors referring to eBPF objects can be duplicated in the
* usual way, using **dup**\ (2) and similar calls.
* * File descriptors referring to eBPF objects can be pinned to the
* filesystem using the **BPF_OBJ_PIN** command of **bpf**\ (2).
*
* An eBPF object is deallocated only after all file descriptors referring
* to the object have been closed and no references remain pinned to the
* filesystem or attached (for example, bound to a program or device).
*/
enum bpf_cmd { enum bpf_cmd {
BPF_MAP_CREATE, BPF_MAP_CREATE,
BPF_MAP_LOOKUP_ELEM, BPF_MAP_LOOKUP_ELEM,