diff options
| -rw-r--r-- | Documentation/bpf/index.rst | 9 | ||||
| -rw-r--r-- | Documentation/userspace-api/ebpf/index.rst | 17 | ||||
| -rw-r--r-- | Documentation/userspace-api/ebpf/syscall.rst | 24 | ||||
| -rw-r--r-- | Documentation/userspace-api/index.rst | 1 | ||||
| -rw-r--r-- | MAINTAINERS | 2 | ||||
| -rw-r--r-- | include/uapi/linux/bpf.h | 714 | ||||
| -rwxr-xr-x | scripts/bpf_doc.py (renamed from scripts/bpf_helpers_doc.py) | 191 | ||||
| -rw-r--r-- | tools/bpf/Makefile.helpers | 60 | ||||
| -rw-r--r-- | tools/bpf/bpftool/.gitignore | 1 | ||||
| -rw-r--r-- | tools/bpf/bpftool/Documentation/Makefile | 11 | ||||
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 714 | ||||
| -rw-r--r-- | tools/lib/bpf/Makefile | 2 | ||||
| -rw-r--r-- | tools/perf/MANIFEST | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/.gitignore | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/Makefile | 20 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/Makefile.docs | 82 | ||||
| -rwxr-xr-x | tools/testing/selftests/bpf/test_bpftool_build.sh | 21 | ||||
| -rwxr-xr-x | tools/testing/selftests/bpf/test_doc_build.sh | 13 |
18 files changed, 1746 insertions, 140 deletions
diff --git a/Documentation/bpf/index.rst b/Documentation/bpf/index.rst index 4f2874b729c3..a702f67dd45f 100644 --- a/Documentation/bpf/index.rst +++ b/Documentation/bpf/index.rst @@ -12,9 +12,6 @@ BPF instruction-set. The Cilium project also maintains a `BPF and XDP Reference Guide`_ that goes into great technical depth about the BPF Architecture. -The primary info for the bpf syscall is available in the `man-pages`_ -for `bpf(2)`_. - BPF Type Format (BTF) ===================== @@ -35,6 +32,12 @@ Two sets of Questions and Answers (Q&A) are maintained. bpf_design_QA bpf_devel_QA +Syscall API +=========== + +The primary info for the bpf syscall is available in the `man-pages`_ +for `bpf(2)`_. For more information about the userspace API, see +Documentation/userspace-api/ebpf/index.rst. Helper functions ================ diff --git a/Documentation/userspace-api/ebpf/index.rst b/Documentation/userspace-api/ebpf/index.rst new file mode 100644 index 000000000000..473dfba78116 --- /dev/null +++ b/Documentation/userspace-api/ebpf/index.rst @@ -0,0 +1,17 @@ +.. SPDX-License-Identifier: GPL-2.0 + +eBPF Userspace API +================== + +eBPF is a kernel mechanism to provide a sandboxed runtime environment in the +Linux kernel for runtime extension and instrumentation without changing kernel +source code or loading kernel modules. eBPF programs can be attached to various +kernel subsystems, including networking, tracing and Linux security modules +(LSM). + +For internal kernel documentation on eBPF, see Documentation/bpf/index.rst. + +.. toctree:: + :maxdepth: 1 + + syscall diff --git a/Documentation/userspace-api/ebpf/syscall.rst b/Documentation/userspace-api/ebpf/syscall.rst new file mode 100644 index 000000000000..ea9918084221 --- /dev/null +++ b/Documentation/userspace-api/ebpf/syscall.rst @@ -0,0 +1,24 @@ +.. SPDX-License-Identifier: GPL-2.0 + +eBPF Syscall +------------ + +:Authors: - Alexei Starovoitov <[email protected]> + - Joe Stringer <[email protected]> + - Michael Kerrisk <[email protected]> + +The primary info for the bpf syscall is available in the `man-pages`_ +for `bpf(2)`_. + +bpf() subcommand reference +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. kernel-doc:: include/uapi/linux/bpf.h + :doc: eBPF Syscall Preamble + +.. kernel-doc:: include/uapi/linux/bpf.h + :doc: eBPF Syscall Commands + +.. Links: +.. _man-pages: https://www.kernel.org/doc/man-pages/ +.. _bpf(2): https://man7.org/linux/man-pages/man2/bpf.2.html diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst index d29b020e5622..1e2438b7afa0 100644 --- a/Documentation/userspace-api/index.rst +++ b/Documentation/userspace-api/index.rst @@ -21,6 +21,7 @@ place where this information is gathered. unshare spec_ctrl accelerators/ocxl + ebpf/index ioctl/index iommu media/index diff --git a/MAINTAINERS b/MAINTAINERS index a50a543e3c81..4446d1455354 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3209,6 +3209,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git T: git git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git F: Documentation/bpf/ F: Documentation/networking/filter.rst +F: Documentation/userspace-api/ebpf/ F: arch/*/net/* F: include/linux/bpf* F: include/linux/filter.h @@ -3223,6 +3224,7 @@ F: net/core/filter.c F: net/sched/act_bpf.c F: net/sched/cls_bpf.c F: samples/bpf/ +F: scripts/bpf_doc.py F: tools/bpf/ F: tools/lib/bpf/ F: tools/testing/selftests/bpf/ diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b89af20cfa19..63a56ed6a785 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -93,7 +93,717 @@ union bpf_iter_link_info { } 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 { BPF_MAP_CREATE, BPF_MAP_LOOKUP_ELEM, @@ -729,7 +1439,7 @@ union bpf_attr { * parsed and used to produce a manual page. The workflow is the following, * and requires the rst2man utility: * - * $ ./scripts/bpf_helpers_doc.py \ + * $ ./scripts/bpf_doc.py \ * --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst * $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7 * $ man /tmp/bpf-helpers.7 diff --git a/scripts/bpf_helpers_doc.py b/scripts/bpf_doc.py index 867ada23281c..2d94025b38e9 100755 --- a/scripts/bpf_helpers_doc.py +++ b/scripts/bpf_doc.py @@ -2,6 +2,7 @@ # SPDX-License-Identifier: GPL-2.0-only # # Copyright (C) 2018-2019 Netronome Systems, Inc. +# Copyright (C) 2021 Isovalent, Inc. # In case user attempts to run with Python 2. from __future__ import print_function @@ -13,6 +14,9 @@ import sys, os class NoHelperFound(BaseException): pass +class NoSyscallCommandFound(BaseException): + pass + class ParsingError(BaseException): def __init__(self, line='<line not provided>', reader=None): if reader: @@ -22,18 +26,27 @@ class ParsingError(BaseException): else: BaseException.__init__(self, 'Error parsing line: %s' % line) -class Helper(object): + +class APIElement(object): """ - An object representing the description of an eBPF helper function. - @proto: function prototype of the helper function - @desc: textual description of the helper function - @ret: description of the return value of the helper function + An object representing the description of an aspect of the eBPF API. + @proto: prototype of the API symbol + @desc: textual description of the symbol + @ret: (optional) description of any associated return value """ def __init__(self, proto='', desc='', ret=''): self.proto = proto self.desc = desc self.ret = ret + +class Helper(APIElement): + """ + An object representing the description of an eBPF helper function. + @proto: function prototype of the helper function + @desc: textual description of the helper function + @ret: description of the return value of the helper function + """ def proto_break_down(self): """ Break down helper function protocol into smaller chunks: return type, @@ -60,6 +73,7 @@ class Helper(object): return res + class HeaderParser(object): """ An object used to parse a file in order to extract the documentation of a @@ -72,6 +86,13 @@ class HeaderParser(object): self.reader = open(filename, 'r') self.line = '' self.helpers = [] + self.commands = [] + + def parse_element(self): + proto = self.parse_symbol() + desc = self.parse_desc() + ret = self.parse_ret() + return APIElement(proto=proto, desc=desc, ret=ret) def parse_helper(self): proto = self.parse_proto() @@ -79,6 +100,18 @@ class HeaderParser(object): ret = self.parse_ret() return Helper(proto=proto, desc=desc, ret=ret) + def parse_symbol(self): + p = re.compile(' \* ?(.+)$') + capture = p.match(self.line) + if not capture: + raise NoSyscallCommandFound + end_re = re.compile(' \* ?NOTES$') + end = end_re.match(self.line) + if end: + raise NoSyscallCommandFound + self.line = self.reader.readline() + return capture.group(1) + def parse_proto(self): # Argument can be of shape: # - "void" @@ -140,16 +173,29 @@ class HeaderParser(object): break return ret - def run(self): - # Advance to start of helper function descriptions. - offset = self.reader.read().find('* Start of BPF helper function descriptions:') + def seek_to(self, target, help_message): + self.reader.seek(0) + offset = self.reader.read().find(target) if offset == -1: - raise Exception('Could not find start of eBPF helper descriptions list') + raise Exception(help_message) self.reader.seek(offset) self.reader.readline() self.reader.readline() self.line = self.reader.readline() + def parse_syscall(self): + self.seek_to('* DOC: eBPF Syscall Commands', + 'Could not find start of eBPF syscall descriptions list') + while True: + try: + command = self.parse_element() + self.commands.append(command) + except NoSyscallCommandFound: + break + + def parse_helpers(self): + self.seek_to('* Start of BPF helper function descriptions:', + 'Could not find start of eBPF helper descriptions list') while True: try: helper = self.parse_helper() @@ -157,6 +203,9 @@ class HeaderParser(object): except NoHelperFound: break + def run(self): + self.parse_syscall() + self.parse_helpers() self.reader.close() ############################################################################### @@ -165,10 +214,11 @@ class Printer(object): """ A generic class for printers. Printers should be created with an array of Helper objects, and implement a way to print them in the desired fashion. - @helpers: array of Helper objects to print to standard output + @parser: A HeaderParser with objects to print to standard output """ - def __init__(self, helpers): - self.helpers = helpers + def __init__(self, parser): + self.parser = parser + self.elements = [] def print_header(self): pass @@ -181,19 +231,23 @@ class Printer(object): def print_all(self): self.print_header() - for helper in self.helpers: - self.print_one(helper) + for elem in self.elements: + self.print_one(elem) self.print_footer() + class PrinterRST(Printer): """ - A printer for dumping collected information about helpers as a ReStructured - Text page compatible with the rst2man program, which can be used to - generate a manual page for the helpers. - @helpers: array of Helper objects to print to standard output + A generic class for printers that print ReStructured Text. Printers should + be created with a HeaderParser object, and implement a way to print API + elements in the desired fashion. + @parser: A HeaderParser with objects to print to standard output """ - def print_header(self): - header = '''\ + def __init__(self, parser): + self.parser = parser + + def print_license(self): + license = '''\ .. Copyright (C) All BPF authors and contributors from 2014 to present. .. See git log include/uapi/linux/bpf.h in kernel tree for details. .. @@ -221,9 +275,39 @@ class PrinterRST(Printer): .. .. Please do not edit this file. It was generated from the documentation .. located in file include/uapi/linux/bpf.h of the Linux kernel sources -.. (helpers description), and from scripts/bpf_helpers_doc.py in the same +.. (helpers description), and from scripts/bpf_doc.py in the same .. repository (header and footer). +''' + print(license) + def print_elem(self, elem): + if (elem.desc): + print('\tDescription') + # Do not strip all newline characters: formatted code at the end of + # a section must be followed by a blank line. + for line in re.sub('\n$', '', elem.desc, count=1).split('\n'): + print('{}{}'.format('\t\t' if line else '', line)) + + if (elem.ret): + print('\tReturn') + for line in elem.ret.rstrip().split('\n'): + print('{}{}'.format('\t\t' if line else '', line)) + + print('') + + +class PrinterHelpersRST(PrinterRST): + """ + A printer for dumping collected information about helpers as a ReStructured + Text page compatible with the rst2man program, which can be used to + generate a manual page for the helpers. + @parser: A HeaderParser with Helper objects to print to standard output + """ + def __init__(self, parser): + self.elements = parser.helpers + + def print_header(self): + header = '''\ =========== BPF-HELPERS =========== @@ -264,6 +348,7 @@ kernel at the top). HELPERS ======= ''' + PrinterRST.print_license(self) print(header) def print_footer(self): @@ -380,27 +465,50 @@ SEE ALSO def print_one(self, helper): self.print_proto(helper) + self.print_elem(helper) - if (helper.desc): - print('\tDescription') - # Do not strip all newline characters: formatted code at the end of - # a section must be followed by a blank line. - for line in re.sub('\n$', '', helper.desc, count=1).split('\n'): - print('{}{}'.format('\t\t' if line else '', line)) - if (helper.ret): - print('\tReturn') - for line in helper.ret.rstrip().split('\n'): - print('{}{}'.format('\t\t' if line else '', line)) +class PrinterSyscallRST(PrinterRST): + """ + A printer for dumping collected information about the syscall API as a + ReStructured Text page compatible with the rst2man program, which can be + used to generate a manual page for the syscall. + @parser: A HeaderParser with APIElement objects to print to standard + output + """ + def __init__(self, parser): + self.elements = parser.commands + + def print_header(self): + header = '''\ +=== +bpf +=== +------------------------------------------------------------------------------- +Perform a command on an extended BPF object +------------------------------------------------------------------------------- + +:Manual section: 2 + +COMMANDS +======== +''' + PrinterRST.print_license(self) + print(header) + + def print_one(self, command): + print('**%s**' % (command.proto)) + self.print_elem(command) - print('') class PrinterHelpers(Printer): """ A printer for dumping collected information about helpers as C header to be included from BPF program. - @helpers: array of Helper objects to print to standard output + @parser: A HeaderParser with Helper objects to print to standard output """ + def __init__(self, parser): + self.elements = parser.helpers type_fwds = [ 'struct bpf_fib_lookup', @@ -511,7 +619,7 @@ class PrinterHelpers(Printer): def print_header(self): header = '''\ -/* This is auto-generated file. See bpf_helpers_doc.py for details. */ +/* This is auto-generated file. See bpf_doc.py for details. */ /* Forward declarations of BPF structs */''' @@ -589,8 +697,13 @@ script = os.path.abspath(sys.argv[0]) linuxRoot = os.path.dirname(os.path.dirname(script)) bpfh = os.path.join(linuxRoot, 'include/uapi/linux/bpf.h') +printers = { + 'helpers': PrinterHelpersRST, + 'syscall': PrinterSyscallRST, +} + argParser = argparse.ArgumentParser(description=""" -Parse eBPF header file and generate documentation for eBPF helper functions. +Parse eBPF header file and generate documentation for the eBPF API. The RST-formatted output produced can be turned into a manual page with the rst2man utility. """) @@ -601,6 +714,8 @@ if (os.path.isfile(bpfh)): default=bpfh) else: argParser.add_argument('--filename', help='path to include/uapi/linux/bpf.h') +argParser.add_argument('target', nargs='?', default='helpers', + choices=printers.keys(), help='eBPF API target') args = argParser.parse_args() # Parse file. @@ -609,7 +724,9 @@ headerParser.run() # Print formatted output to standard output. if args.header: - printer = PrinterHelpers(headerParser.helpers) + if args.target != 'helpers': + raise NotImplementedError('Only helpers header generation is supported') + printer = PrinterHelpers(headerParser) else: - printer = PrinterRST(headerParser.helpers) + printer = printers[args.target](headerParser) printer.print_all() diff --git a/tools/bpf/Makefile.helpers b/tools/bpf/Makefile.helpers deleted file mode 100644 index 854d084026dd..000000000000 --- a/tools/bpf/Makefile.helpers +++ /dev/null @@ -1,60 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0-only -ifndef allow-override - include ../scripts/Makefile.include - include ../scripts/utilities.mak -else - # Assume Makefile.helpers is being run from bpftool/Documentation - # subdirectory. Go up two more directories to fetch bpf.h header and - # associated script. - UP2DIR := ../../ -endif - -INSTALL ?= install -RM ?= rm -f -RMDIR ?= rmdir --ignore-fail-on-non-empty - -ifeq ($(V),1) - Q = -else - Q = @ -endif - -prefix ?= /usr/local -mandir ?= $(prefix)/man -man7dir = $(mandir)/man7 - -HELPERS_RST = bpf-helpers.rst -MAN7_RST = $(HELPERS_RST) - -_DOC_MAN7 = $(patsubst %.rst,%.7,$(MAN7_RST)) -DOC_MAN7 = $(addprefix $(OUTPUT),$(_DOC_MAN7)) - -helpers: man7 -man7: $(DOC_MAN7) - -RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null) - -$(OUTPUT)$(HELPERS_RST): $(UP2DIR)../../include/uapi/linux/bpf.h - $(QUIET_GEN)$(UP2DIR)../../scripts/bpf_helpers_doc.py --filename $< > $@ - -$(OUTPUT)%.7: $(OUTPUT)%.rst -ifndef RST2MAN_DEP - $(error "rst2man not found, but required to generate man pages") -endif - $(QUIET_GEN)rst2man $< > $@ - -helpers-clean: - $(call QUIET_CLEAN, eBPF_helpers-manpage) - $(Q)$(RM) $(DOC_MAN7) $(OUTPUT)$(HELPERS_RST) - -helpers-install: helpers - $(call QUIET_INSTALL, eBPF_helpers-manpage) - $(Q)$(INSTALL) -d -m 755 $(DESTDIR)$(man7dir) - $(Q)$(INSTALL) -m 644 $(DOC_MAN7) $(DESTDIR)$(man7dir) - -helpers-uninstall: - $(call QUIET_UNINST, eBPF_helpers-manpage) - $(Q)$(RM) $(addprefix $(DESTDIR)$(man7dir)/,$(_DOC_MAN7)) - $(Q)$(RMDIR) $(DESTDIR)$(man7dir) - -.PHONY: helpers helpers-clean helpers-install helpers-uninstall diff --git a/tools/bpf/bpftool/.gitignore b/tools/bpf/bpftool/.gitignore index 944cb4b7c95d..05ce4446b780 100644 --- a/tools/bpf/bpftool/.gitignore +++ b/tools/bpf/bpftool/.gitignore @@ -3,7 +3,6 @@ /bootstrap/ /bpftool bpftool*.8 -bpf-helpers.* FEATURE-DUMP.bpftool feature libbpf diff --git a/tools/bpf/bpftool/Documentation/Makefile b/tools/bpf/bpftool/Documentation/Makefile index f33cb02de95c..c49487905ceb 100644 --- a/tools/bpf/bpftool/Documentation/Makefile +++ b/tools/bpf/bpftool/Documentation/Makefile @@ -16,15 +16,12 @@ prefix ?= /usr/local mandir ?= $(prefix)/man man8dir = $(mandir)/man8 -# Load targets for building eBPF helpers man page. -include ../../Makefile.helpers - MAN8_RST = $(wildcard bpftool*.rst) _DOC_MAN8 = $(patsubst %.rst,%.8,$(MAN8_RST)) DOC_MAN8 = $(addprefix $(OUTPUT),$(_DOC_MAN8)) -man: man8 helpers +man: man8 man8: $(DOC_MAN8) RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null) @@ -46,16 +43,16 @@ ifndef RST2MAN_DEP endif $(QUIET_GEN)( cat $< ; printf "%b" $(call see_also,$<) ) | rst2man $(RST2MAN_OPTS) > $@ -clean: helpers-clean +clean: $(call QUIET_CLEAN, Documentation) $(Q)$(RM) $(DOC_MAN8) -install: man helpers-install +install: man $(call QUIET_INSTALL, Documentation-man) $(Q)$(INSTALL) -d -m 755 $(DESTDIR)$(man8dir) $(Q)$(INSTALL) -m 644 $(DOC_MAN8) $(DESTDIR)$(man8dir) -uninstall: helpers-uninstall +uninstall: $(call QUIET_UNINST, Documentation-man) $(Q)$(RM) $(addprefix $(DESTDIR)$(man8dir)/,$(_DOC_MAN8)) $(Q)$(RMDIR) $(DESTDIR)$(man8dir) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index b89af20cfa19..63a56ed6a785 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -93,7 +93,717 @@ union bpf_iter_link_info { } 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 { BPF_MAP_CREATE, BPF_MAP_LOOKUP_ELEM, @@ -729,7 +1439,7 @@ union bpf_attr { * parsed and used to produce a manual page. The workflow is the following, * and requires the rst2man utility: * - * $ ./scripts/bpf_helpers_doc.py \ + * $ ./scripts/bpf_doc.py \ * --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst * $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7 * $ man /tmp/bpf-helpers.7 diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 887a494ad5fc..8170f88e8ea6 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -158,7 +158,7 @@ $(BPF_IN_STATIC): force $(BPF_HELPER_DEFS) $(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR) $(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h - $(QUIET_GEN)$(srctree)/scripts/bpf_helpers_doc.py --header \ + $(QUIET_GEN)$(srctree)/scripts/bpf_doc.py --header \ --file $(srctree)/tools/include/uapi/linux/bpf.h > $(BPF_HELPER_DEFS) $(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION) diff --git a/tools/perf/MANIFEST b/tools/perf/MANIFEST index 5d7b947320fb..f05c4d48fd7e 100644 --- a/tools/perf/MANIFEST +++ b/tools/perf/MANIFEST @@ -20,4 +20,4 @@ tools/lib/bitmap.c tools/lib/str_error_r.c tools/lib/vsprintf.c tools/lib/zalloc.c -scripts/bpf_helpers_doc.py +scripts/bpf_doc.py diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index c0c48fdb9ac1..4866f6a21901 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -1,4 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only +bpf-helpers* +bpf-syscall* test_verifier test_maps test_lru_map diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index a81af15e4ded..b5827464c6b5 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -68,6 +68,7 @@ TEST_PROGS := test_kmod.sh \ test_bpftool_build.sh \ test_bpftool.sh \ test_bpftool_metadata.sh \ + test_docs_build.sh \ test_xsk.sh TEST_PROGS_EXTENDED := with_addr.sh \ @@ -103,6 +104,7 @@ override define CLEAN $(call msg,CLEAN) $(Q)$(RM) -r $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(EXTRA_CLEAN) $(Q)$(MAKE) -C bpf_testmod clean + $(Q)$(MAKE) docs-clean endef include ../lib.mk @@ -180,6 +182,7 @@ $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) cp $(SCRATCH_DIR)/runqslower $@ $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/test_stub.o $(BPFOBJ) +$(TEST_GEN_FILES): docs $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c $(OUTPUT)/test_skb_cgroup_id_user: cgroup_helpers.c @@ -200,11 +203,16 @@ $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) \ CC=$(HOSTCC) LD=$(HOSTLD) \ OUTPUT=$(HOST_BUILD_DIR)/bpftool/ \ prefix= DESTDIR=$(HOST_SCRATCH_DIR)/ install - $(Q)mkdir -p $(BUILD_DIR)/bpftool/Documentation - $(Q)RST2MAN_OPTS="--exit-status=1" $(MAKE) $(submake_extras) \ - -C $(BPFTOOLDIR)/Documentation \ - OUTPUT=$(BUILD_DIR)/bpftool/Documentation/ \ - prefix= DESTDIR=$(SCRATCH_DIR)/ install + +docs: + $(Q)RST2MAN_OPTS="--exit-status=1" $(MAKE) $(submake_extras) \ + -f Makefile.docs \ + prefix= OUTPUT=$(OUTPUT)/ DESTDIR=$(OUTPUT)/ $@ + +docs-clean: + $(Q)$(MAKE) $(submake_extras) \ + -f Makefile.docs \ + prefix= OUTPUT=$(OUTPUT)/ DESTDIR=$(OUTPUT)/ $@ $(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ ../../../include/uapi/linux/bpf.h \ @@ -477,3 +485,5 @@ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ prog_tests/tests.h map_tests/tests.h verifier/tests.h \ feature \ $(addprefix $(OUTPUT)/,*.o *.skel.h no_alu32 bpf_gcc bpf_testmod.ko) + +.PHONY: docs docs-clean diff --git a/tools/testing/selftests/bpf/Makefile.docs b/tools/testing/selftests/bpf/Makefile.docs new file mode 100644 index 000000000000..ccf260021e83 --- /dev/null +++ b/tools/testing/selftests/bpf/Makefile.docs @@ -0,0 +1,82 @@ +# SPDX-License-Identifier: GPL-2.0-only + +include ../../../scripts/Makefile.include +include ../../../scripts/utilities.mak + +INSTALL ?= install +RM ?= rm -f +RMDIR ?= rmdir --ignore-fail-on-non-empty + +ifeq ($(V),1) + Q = +else + Q = @ +endif + +prefix ?= /usr/local +mandir ?= $(prefix)/man +man2dir = $(mandir)/man2 +man7dir = $(mandir)/man7 + +SYSCALL_RST = bpf-syscall.rst +MAN2_RST = $(SYSCALL_RST) + +HELPERS_RST = bpf-helpers.rst +MAN7_RST = $(HELPERS_RST) + +_DOC_MAN2 = $(patsubst %.rst,%.2,$(MAN2_RST)) +DOC_MAN2 = $(addprefix $(OUTPUT),$(_DOC_MAN2)) + +_DOC_MAN7 = $(patsubst %.rst,%.7,$(MAN7_RST)) +DOC_MAN7 = $(addprefix $(OUTPUT),$(_DOC_MAN7)) + +DOCTARGETS := helpers syscall + +docs: $(DOCTARGETS) +syscall: man2 +helpers: man7 +man2: $(DOC_MAN2) +man7: $(DOC_MAN7) + +RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null) + +# Configure make rules for the man page bpf-$1.$2. +# $1 - target for scripts/bpf_doc.py +# $2 - man page section to generate the troff file +define DOCS_RULES = +$(OUTPUT)bpf-$1.rst: ../../../../include/uapi/linux/bpf.h + $$(QUIET_GEN)../../../../scripts/bpf_doc.py $1 \ + --filename $$< > $$@ + +$(OUTPUT)%.$2: $(OUTPUT)%.rst +ifndef RST2MAN_DEP + $$(error "rst2man not found, but required to generate man pages") +endif + $$(QUIET_GEN)rst2man $$< > $$@ + +docs-clean-$1: + $$(call QUIET_CLEAN, eBPF_$1-manpage) + $(Q)$(RM) $$(DOC_MAN$2) $(OUTPUT)bpf-$1.rst + +docs-install-$1: docs + $$(call QUIET_INSTALL, eBPF_$1-manpage) + $(Q)$(INSTALL) -d -m 755 $(DESTDIR)$$(man$2dir) + $(Q)$(INSTALL) -m 644 $$(DOC_MAN$2) $(DESTDIR)$$(man$2dir) + +docs-uninstall-$1: + $$(call QUIET_UNINST, eBPF_$1-manpage) + $(Q)$(RM) $$(addprefix $(DESTDIR)$$(man$2dir)/,$$(_DOC_MAN$2)) + $(Q)$(RMDIR) $(DESTDIR)$$(man$2dir) + +.PHONY: $1 docs-clean-$1 docs-install-$1 docs-uninstall-$1 +endef + +# Create the make targets to generate manual pages by name and section +$(eval $(call DOCS_RULES,helpers,7)) +$(eval $(call DOCS_RULES,syscall,2)) + +docs-clean: $(foreach doctarget,$(DOCTARGETS), docs-clean-$(doctarget)) +docs-install: $(foreach doctarget,$(DOCTARGETS), docs-install-$(doctarget)) +docs-uninstall: $(foreach doctarget,$(DOCTARGETS), docs-uninstall-$(doctarget)) + +.PHONY: docs docs-clean docs-install docs-uninstall man2 man7 diff --git a/tools/testing/selftests/bpf/test_bpftool_build.sh b/tools/testing/selftests/bpf/test_bpftool_build.sh index 2db3c60e1e61..ac349a5cea7e 100755 --- a/tools/testing/selftests/bpf/test_bpftool_build.sh +++ b/tools/testing/selftests/bpf/test_bpftool_build.sh @@ -85,23 +85,6 @@ make_with_tmpdir() { echo } -make_doc_and_clean() { - echo -e "\$PWD: $PWD" - echo -e "command: make -s $* doc >/dev/null" - RST2MAN_OPTS="--exit-status=1" make $J -s $* doc - if [ $? -ne 0 ] ; then - ERROR=1 - printf "FAILURE: Errors or warnings when building documentation\n" - fi - ( - if [ $# -ge 1 ] ; then - cd ${@: -1} - fi - make -s doc-clean - ) - echo -} - echo "Trying to build bpftool" echo -e "... through kbuild\n" @@ -162,7 +145,3 @@ make_and_clean make_with_tmpdir OUTPUT make_with_tmpdir O - -echo -e "Checking documentation build\n" -# From tools/bpf/bpftool -make_doc_and_clean diff --git a/tools/testing/selftests/bpf/test_doc_build.sh b/tools/testing/selftests/bpf/test_doc_build.sh new file mode 100755 index 000000000000..7eb940a7b2eb --- /dev/null +++ b/tools/testing/selftests/bpf/test_doc_build.sh @@ -0,0 +1,13 @@ +#!/bin/bash +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + +# Assume script is located under tools/testing/selftests/bpf/. We want to start +# build attempts from the top of kernel repository. +SCRIPT_REL_PATH=$(realpath --relative-to=$PWD $0) +SCRIPT_REL_DIR=$(dirname $SCRIPT_REL_PATH) +KDIR_ROOT_DIR=$(realpath $PWD/$SCRIPT_REL_DIR/../../../../) +cd $KDIR_ROOT_DIR + +for tgt in docs docs-clean; do + make -s -C $PWD/$SCRIPT_REL_DIR $tgt; +done |