- 12 Jul, 2018 8 commits
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Russell King authored
The decision about whether a BPF register is on the stack or in a CPU register is detected at the top BPF insn processing level, and then percolated throughout the remainder of the code. Since we now use negative register values to represent stacked registers, we can detect where a BPF register is stored without restoring to carrying this additional metadata through all code paths. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Russell King authored
Use negative numbers for eBPF registers that live on the stack. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Russell King authored
Provide a set of load/store opcode generators that work with negative immediates as well as positive ones. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Russell King authored
Enumerate the contents of the JIT scratch stack layout used for storing some of the JITs 64-bit registers, tail call counter and AX register. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Daniel Borkmann authored
Quentin Monnet says: ==================== The three patches in this series are related to the documentation for eBPF helpers. The first patch brings minor formatting edits to the documentation in include/uapi/linux/bpf.h, and the second one updates the related header file under tools/. The third patch adds a Makefile under tools/bpf for generating the documentation (man pages) about eBPF helpers. The targets defined in this file can also be called from the bpftool directory (please refer to relevant commit logs for details). ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Quentin Monnet authored
Provide a new Makefile.helpers in tools/bpf, in order to build and install the man page for eBPF helpers. This Makefile is also included in the one used to build bpftool documentation, so that it can be called either on its own (cd tools/bpf && make -f Makefile.helpers) or from bpftool directory (cd tools/bpf/bpftool && make doc, or cd tools/bpf/bpftool/Documentation && make helpers). Makefile.helpers is not added directly to bpftool to avoid changing its Makefile too much (helpers are not 100% directly related with bpftool). But the possibility to build the page from bpftool directory makes us able to package the helpers man page with bpftool, and to install it along with bpftool documentation, so that the doc for helpers becomes easily available to developers through the "man" program. Cc: linux-man@vger.kernel.org Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Quentin Monnet authored
Update with latest changes from include/uapi/linux/bpf.h header. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Quentin Monnet authored
Minor formatting edits for eBPF helpers documentation, including blank lines removal, fix of item list for return values in bpf_fib_lookup(), and missing prefix on bpf_skb_load_bytes_relative(). Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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- 11 Jul, 2018 14 commits
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Daniel Borkmann authored
Jakub Kicinski says: ==================== This series starts with two minor clean ups to test_offload.py selftest script. The next 11 patches extend the abilities of bpftool prog load beyond the simple cgroup use cases. Three new parameters are added: - type - allows specifying program type, independent of how code sections are named; - map - allows reusing existing maps, instead of creating a new map on every program load; - dev - offload/binding to a device. A number of changes to libbpf is required to accomplish the task. The section - program type logic mapping is exposed. We should probably aim to use the libbpf program section naming everywhere. For reuse of maps we need to allow users to set FD for bpf map object in libbpf. Examples Load program my_xdp.o and pin it as /sys/fs/bpf/my_xdp, for xdp program type: $ bpftool prog load my_xdp.o /sys/fs/bpf/my_xdp \ type xdp As above but for offload: $ bpftool prog load my_xdp.o /sys/fs/bpf/my_xdp \ type xdp \ dev netdevsim0 Load program my_maps.o, but for the first map reuse map id 17, and for the map called "other_map" reuse pinned map /sys/fs/bpf/map0: $ bpftool prog load my_maps.o /sys/fs/bpf/prog \ map idx 0 id 17 \ map name other_map pinned /sys/fs/bpf/map0 v3: - fix return codes in patch 5; - rename libbpf_prog_type_by_string() -> libbpf_prog_type_by_name(); - fold file path into xattr in patch 8; - add patch 10; - use dup3() in patch 12; - depend on fd value in patch 12; - close old fd in patch 12. v2: - add compat for reallocarray(). ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Add map parameter to prog load which will allow reuse of existing maps instead of creating new ones. We need feature detection and compat code for reallocarray, since it's not available in many libc versions. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
More advanced applications may want to only replace programs without destroying associated maps. Allow libbpf users to achieve that. Instead of always creating all of the maps at load time, expose to users an API to reconstruct the map object from already existing map. The map parameters are read from the kernel and replace the parameters of the ELF map. libbpf does not restrict the map replacement, i.e. the reused map does not have to be compatible with the ELF map definition. We relay on the verifier for checking the compatibility between maps and programs. The ELF map definition is completely overwritten by the information read from the kernel, to make sure libbpf's view of map object corresponds to the actual map. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
reallocarray() is a safer variant of realloc which checks for multiplication overflow in case of array allocation. Since it's not available in Glibc < 2.26 import kernel's overflow.h and add a static inline implementation when needed. Use feature detection to probe for existence of reallocarray. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
libbpf_strerror() depends on XSI-compliant (POSIX) version of strerror_r(), which prevents us from using GNU-extensions in libbpf.c, like reallocarray() or dup3(). Move error printing code into a separate file to allow it to continue using POSIX strerror_r(). No functional changes. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
bpf_prog_load() is a very useful helper but it doesn't give us full flexibility of modifying the BPF objects before loading. Open code bpf_prog_load() in bpftool so we can add extra logic in following commits. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Similarly to bpf_prog_load() users of bpf_object__open() may need to specify the expected program type. Program type is needed at open to avoid the kernel version check for program types which don't require it. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Add helper to libbpf for recognizing maps which should not have ifindex set when program is loaded. These maps only contain host metadata and therefore are not marked for offload, e.g. the perf event map. Use this helper in bpf_prog_load_xattr(). Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Sometimes program section names don't match with libbpf's expectation. In particular XDP's default section names differ between libbpf and iproute2. Allow users to pass program type on command line. Name the types like the libbpf expected section names. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
libbpf can guess program type based on ELF section names. As libbpf becomes more popular its association between section name strings and types becomes more of a standard. Allow libbpf users to use the same logic for matching strings to types, e.g. when the string originates from command line. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Extend the bpftool prog load command to also accept "dev" parameter, which will allow us to load programs onto devices. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Add a new macro for printing more informative message than straight usage() when parameters are missing, and use it for prog do_load(). Save the object and pin path argument to variables for clarity. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Currently the test only checks errors, not warnings, so save typing and prefix the extack messages with "Error:" inside the check helper. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jakub Kicinski authored
Trivial removal of duplicated "mode" in error message. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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- 06 Jul, 2018 13 commits
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Daniel Borkmann authored
Jiong Wang says: ==================== NFP supports u16 and u32 multiplication. Multiplication is done 8-bits per step, therefore we need 2 steps for u16 and 4 steps for u32. We also need one start instruction to initialize the sequence and one or two instructions to fetch the result depending on either you need the high halve of u32 multiplication. For ALU64, if either operand is beyond u32's value range, we reject it. One thing to note, if the source operand is BPF_K, then we need to check "imm" field directly, and we'd reject it if it is negative. Because for ALU64, "imm" (with s32 type) is expected to be sign extended to s64 which NFP mul doesn't support. For ALU32, it is fine for "imm" be negative though, because the result is 32-bits and here is no difference on the low halve of result for signed/unsigned mul, so we will get correct result. NFP doesn't have integer divide instruction, this patch set uses reciprocal algorithm (the basic one, reciprocal_div) to emulate it. For each u32 divide, we would need 11 instructions to finish the operation. 7 (for multiplication) + 4 (various ALUs) = 11 Given NFP only supports multiplication no bigger than u32, we'd require divisor and dividend no bigger than that as well. Also eBPF doesn't support signed divide and has enforced this on C language level by failing compilation. However LLVM assembler hasn't enforced this, so it is possible for negative constant to leak in as a BPF_K operand through assembly code, we reject such cases as well. Meanwhile reciprocal_div.h only implemented the basic version of: "Division by Invariant Integers Using Multiplication" - Torbjörn Granlund and Peter L. Montgomery This patch set further implements the optimized version (Figure 4.2 in the paper) inside existing reciprocal_div.h. When the divider is even and the calculated reciprocal magic number doesn't fit u32, we could reduce the required ALU instructions from 4 to 2 or 1 for some cases. The advanced version requires more complex calculation to get the reciprocal multiplier and other control variables, but then could reduce the required emulation operations. It makes sense to use it for JIT divide code generation (for example eBPF JIT backends) for which we are willing to trade performance of JITed code with that of host. v2: - add warning in l == 32 code path. (Song Liu/Jakub) - jit separate insn sequence for l == 32. (Jakub/Edwin) - should use unrestricted operand for mul. - once place should use "1U << exp" instead of "1 << exp". ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
As we are doing JIT, we would want to use the advanced version of the reciprocal divide (reciprocal_value_adv) to trade performance with host. We could reduce the required ALU instructions from 4 to 2 or 1. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
NFP doesn't have integer divide instruction, this patch use reciprocal algorithm (the basic one, reciprocal_div) to emulate it. For each u32 divide, we would need 11 instructions to finish the operation. 7 (for multiplication) + 4 (various ALUs) = 11 Given NFP only supports multiplication no bigger than u32, we'd require divisor and dividend no bigger than that as well. Also eBPF doesn't support signed divide and has enforced this on C language level by failing compilation. However LLVM assembler hasn't enforced this, so it is possible for negative constant to leak in as a BPF_K operand through assembly code, we reject such cases as well. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
NFP supports u16 and u32 multiplication. Multiplication is done 8-bits per step, therefore we need 2 steps for u16 and 4 steps for u32. We also need one start instruction to initialize the sequence and one or two instructions to fetch the result depending on either you need the high halve of u32 multiplication. For ALU64, if either operand is beyond u32's value range, we reject it. One thing to note, if the source operand is BPF_K, then we need to check "imm" field directly, and we'd reject it if it is negative. Because for ALU64, "imm" (with s32 type) is expected to be sign extended to s64 which NFP mul doesn't support. For ALU32, it is fine for "imm" be negative though, because the result is 32-bits and here is no difference on the low halve of result for signed/unsigned mul, so we will get correct result. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
NFP verifier hook is coping range information of the shift amount for indirect shift operation so optimized shift sequences could be generated. We want to use range info to do more things. For example, to decide whether multiplication and divide are supported on the given range. This patch simply let NFP verifier hook to copy range info for all operands of all ALU operands. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
The two fields are a copy of umin and umax info of bpf_insn->src_reg generated by verifier. Rename to make their meaning clear. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Jiong Wang authored
The new added "reciprocal_value_adv" implements the advanced version of the algorithm described in Figure 4.2 of the paper except when "divisor > (1U << 31)" whose ceil(log2(d)) result will be 32 which then requires u128 divide on host. The exception case could be easily handled before calling "reciprocal_value_adv". The advanced version requires more complex calculation to get the reciprocal multiplier and other control variables, but then could reduce the required emulation operations. It makes no sense to use this advanced version for host divide emulation, those extra complexities for calculating multiplier etc could completely waive our saving on emulation operations. However, it makes sense to use it for JIT divide code generation (for example eBPF JIT backends) for which we are willing to trade performance of JITed code with that of host. As shown by the following pseudo code, the required emulation operations could go down from 6 (the basic version) to 3 or 4. To use the result of "reciprocal_value_adv", suppose we want to calculate n/d, the C-style pseudo code will be the following, it could be easily changed to real code generation for other JIT targets. struct reciprocal_value_adv rvalue; u8 pre_shift, exp; // handle exception case. if (d >= (1U << 31)) { result = n >= d; return; } rvalue = reciprocal_value_adv(d, 32) exp = rvalue.exp; if (rvalue.is_wide_m && !(d & 1)) { // floor(log2(d & (2^32 -d))) pre_shift = fls(d & -d) - 1; rvalue = reciprocal_value_adv(d >> pre_shift, 32 - pre_shift); } else { pre_shift = 0; } // code generation starts. if (imm == 1U << exp) { result = n >> exp; } else if (rvalue.is_wide_m) { // pre_shift must be zero when reached here. t = (n * rvalue.m) >> 32; result = n - t; result >>= 1; result += t; result >>= rvalue.sh - 1; } else { if (pre_shift) result = n >> pre_shift; result = ((u64)result * rvalue.m) >> 32; result >>= rvalue.sh; } Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Roman Gushchin authored
This commit adds a bash completion to the bpftool cgroup tree command. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Jakub Kicinski <jakub.kicinski@netronome.com> Cc: Quentin Monnet <quentin.monnet@netronome.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Roman Gushchin authored
Describe cgroup tree command in the corresponding bpftool man page. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Cc: Quentin Monnet <quentin.monnet@netronome.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Roman Gushchin authored
This commit introduces a new bpftool command: cgroup tree. The idea is to iterate over the whole cgroup tree and print all attached programs. I was debugging a bpf/systemd issue, and found, that there is no simple way to listen all bpf programs attached to cgroups. I did master something in bash, but after some time got tired of it, and decided, that adding a dedicated bpftool command could be a better idea. So, here it is: $ sudo ./bpftool cgroup tree CgroupPath ID AttachType AttachFlags Name /sys/fs/cgroup/system.slice/systemd-machined.service 18 ingress 17 egress /sys/fs/cgroup/system.slice/systemd-logind.service 20 ingress 19 egress /sys/fs/cgroup/system.slice/systemd-udevd.service 16 ingress 15 egress /sys/fs/cgroup/system.slice/systemd-journald.service 14 ingress 13 egress Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Cc: Quentin Monnet <quentin.monnet@netronome.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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David S. Miller authored
Edward Cree says: ==================== IP listification follow-ups While working on IPv6 list processing, I found another bug in the IPv4 version. So this patch series has that fix, and the IPv6 version with both fixes incorporated. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Edward Cree authored
Essentially the same as the ipv4 equivalents. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Edward Cree authored
If we have an L3 master device, l3mdev_ip_rcv() will steal the skb, but we were returning NET_RX_SUCCESS from ip_rcv_finish_core() which meant that ip_list_rcv_finish() would keep it on the list. Instead let's move the l3mdev_ip_rcv() call into the caller, so that our response to a steal can be different in the single packet path (return NET_RX_SUCCESS) and the list path (forget this packet and continue). Fixes: 5fa12739 ("net: ipv4: listify ip_rcv_finish") Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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- 05 Jul, 2018 5 commits
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Gustavo A. R. Silva authored
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Warning level 2 was used: -Wimplicit-fallthrough=2 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Gustavo A. R. Silva authored
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Gustavo A. R. Silva authored
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Warning level 2 was used: -Wimplicit-fallthrough=2 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Ganesh Goudar authored
Use 'chip_ver' rather than 'chip' to check if the card is T5. Fixes: e8d45292 ("cxgb4: clean up init_one") Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Colin Ian King authored
Variables adv and lpa are being assigned but are never used hence they are redundant and can be removed. Also remove the unncessary mii_reads too. Cleans up clang warnings: warning: variable 'lpa' set but not used [-Wunused-but-set-variable] warning: variable 'adv' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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