From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ... --- tools/testing/selftests/vm/cow.c | 1536 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 1536 insertions(+) create mode 100644 tools/testing/selftests/vm/cow.c (limited to 'tools/testing/selftests/vm/cow.c') diff --git a/tools/testing/selftests/vm/cow.c b/tools/testing/selftests/vm/cow.c new file mode 100644 index 000000000..26f6ea307 --- /dev/null +++ b/tools/testing/selftests/vm/cow.c @@ -0,0 +1,1536 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * COW (Copy On Write) tests. + * + * Copyright 2022, Red Hat, Inc. + * + * Author(s): David Hildenbrand + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "local_config.h" +#ifdef LOCAL_CONFIG_HAVE_LIBURING +#include +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + +#include "../../../../mm/gup_test.h" +#include "../kselftest.h" +#include "vm_util.h" + +static size_t pagesize; +static int pagemap_fd; +static size_t thpsize; +static int nr_hugetlbsizes; +static size_t hugetlbsizes[10]; +static int gup_fd; +static bool has_huge_zeropage; + +static void detect_thpsize(void) +{ + int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", + O_RDONLY); + size_t size = 0; + char buf[15]; + int ret; + + if (fd < 0) + return; + + ret = pread(fd, buf, sizeof(buf), 0); + if (ret > 0 && ret < sizeof(buf)) { + buf[ret] = 0; + + size = strtoul(buf, NULL, 10); + if (size < pagesize) + size = 0; + if (size > 0) { + thpsize = size; + ksft_print_msg("[INFO] detected THP size: %zu KiB\n", + thpsize / 1024); + } + } + + close(fd); +} + +static void detect_huge_zeropage(void) +{ + int fd = open("/sys/kernel/mm/transparent_hugepage/use_zero_page", + O_RDONLY); + size_t enabled = 0; + char buf[15]; + int ret; + + if (fd < 0) + return; + + ret = pread(fd, buf, sizeof(buf), 0); + if (ret > 0 && ret < sizeof(buf)) { + buf[ret] = 0; + + enabled = strtoul(buf, NULL, 10); + if (enabled == 1) { + has_huge_zeropage = true; + ksft_print_msg("[INFO] huge zeropage is enabled\n"); + } + } + + close(fd); +} + +static void detect_hugetlbsizes(void) +{ + DIR *dir = opendir("/sys/kernel/mm/hugepages/"); + + if (!dir) + return; + + while (nr_hugetlbsizes < ARRAY_SIZE(hugetlbsizes)) { + struct dirent *entry = readdir(dir); + size_t kb; + + if (!entry) + break; + if (entry->d_type != DT_DIR) + continue; + if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1) + continue; + hugetlbsizes[nr_hugetlbsizes] = kb * 1024; + nr_hugetlbsizes++; + ksft_print_msg("[INFO] detected hugetlb size: %zu KiB\n", + kb); + } + closedir(dir); +} + +static bool range_is_swapped(void *addr, size_t size) +{ + for (; size; addr += pagesize, size -= pagesize) + if (!pagemap_is_swapped(pagemap_fd, addr)) + return false; + return true; +} + +struct comm_pipes { + int child_ready[2]; + int parent_ready[2]; +}; + +static int setup_comm_pipes(struct comm_pipes *comm_pipes) +{ + if (pipe(comm_pipes->child_ready) < 0) + return -errno; + if (pipe(comm_pipes->parent_ready) < 0) { + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + return -errno; + } + + return 0; +} + +static void close_comm_pipes(struct comm_pipes *comm_pipes) +{ + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + close(comm_pipes->parent_ready[0]); + close(comm_pipes->parent_ready[1]); +} + +static int child_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + char *old = malloc(size); + char buf; + + /* Backup the original content. */ + memcpy(old, mem, size); + + /* Wait until the parent modified the page. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values. */ + return memcmp(old, mem, size); +} + +static int child_vmsplice_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + char *old, *new; + int fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + /* Backup the original content. */ + memcpy(old, mem, size); + + if (pipe(fds) < 0) + return -errno; + + /* Trigger a read-only pin. */ + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred < 0) + return -errno; + if (transferred == 0) + return -EINVAL; + + /* Unmap it from our page tables. */ + if (munmap(mem, size) < 0) + return -errno; + + /* Wait until the parent modified it. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values via the pipe. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) + return -errno; + } + + return memcmp(old, new, transferred); +} + +typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes); + +static void do_test_cow_in_parent(char *mem, size_t size, bool do_mprotect, + child_fn fn) +{ + struct comm_pipes comm_pipes; + char buf; + int ret; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + exit(fn(mem, size, &comm_pipes)); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + + if (do_mprotect) { + /* + * mprotect() optimizations might try avoiding + * write-faults by directly mapping pages writable. + */ + ret = mprotect(mem, size, PROT_READ); + ret |= mprotect(mem, size, PROT_READ|PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + goto close_comm_pipes; + } + } + + /* Modify the page. */ + memset(mem, 0xff, size); + write(comm_pipes.parent_ready[1], "0", 1); + + wait(&ret); + if (WIFEXITED(ret)) + ret = WEXITSTATUS(ret); + else + ret = -EINVAL; + + ksft_test_result(!ret, "No leak from parent into child\n"); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_cow_in_parent(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, false, child_memcmp_fn); +} + +static void test_cow_in_parent_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_memcmp_fn); +} + +static void test_vmsplice_in_child(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, false, child_vmsplice_memcmp_fn); +} + +static void test_vmsplice_in_child_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_vmsplice_memcmp_fn); +} + +static void do_test_vmsplice_in_parent(char *mem, size_t size, + bool before_fork) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + struct comm_pipes comm_pipes; + char *old, *new; + int ret, fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + memcpy(old, mem, size); + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free; + } + + if (pipe(fds) < 0) { + ksft_test_result_fail("pipe() failed\n"); + goto close_comm_pipes; + } + + if (before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + goto close_pipe; + } + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_pipe; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + /* Modify page content in the child. */ + memset(mem, 0xff, size); + exit(0); + } + + if (!before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + wait(&ret); + goto close_pipe; + } + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + if (munmap(mem, size) < 0) { + ksft_test_result_fail("munmap() failed\n"); + goto close_pipe; + } + write(comm_pipes.parent_ready[1], "0", 1); + + /* Wait until the child is done writing. */ + wait(&ret); + if (!WIFEXITED(ret)) { + ksft_test_result_fail("wait() failed\n"); + goto close_pipe; + } + + /* See if we still read the old values. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) { + ksft_test_result_fail("read() failed\n"); + goto close_pipe; + } + } + + ksft_test_result(!memcmp(old, new, transferred), + "No leak from child into parent\n"); +close_pipe: + close(fds[0]); + close(fds[1]); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free: + free(old); + free(new); +} + +static void test_vmsplice_before_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, true); +} + +static void test_vmsplice_after_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, false); +} + +#ifdef LOCAL_CONFIG_HAVE_LIBURING +static void do_test_iouring(char *mem, size_t size, bool use_fork) +{ + struct comm_pipes comm_pipes; + struct io_uring_cqe *cqe; + struct io_uring_sqe *sqe; + struct io_uring ring; + ssize_t cur, total; + struct iovec iov; + char *buf, *tmp; + int ret, fd; + FILE *file; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + file = tmpfile(); + if (!file) { + ksft_test_result_fail("tmpfile() failed\n"); + goto close_comm_pipes; + } + fd = fileno(file); + assert(fd); + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + goto close_file; + } + + /* Skip on errors, as we might just lack kernel support. */ + ret = io_uring_queue_init(1, &ring, 0); + if (ret < 0) { + ksft_test_result_skip("io_uring_queue_init() failed\n"); + goto free_tmp; + } + + /* + * Register the range as a fixed buffer. This will FOLL_WRITE | FOLL_PIN + * | FOLL_LONGTERM the range. + * + * Skip on errors, as we might just lack kernel support or might not + * have sufficient MEMLOCK permissions. + */ + iov.iov_base = mem; + iov.iov_len = size; + ret = io_uring_register_buffers(&ring, &iov, 1); + if (ret) { + ksft_test_result_skip("io_uring_register_buffers() failed\n"); + goto queue_exit; + } + + if (use_fork) { + /* + * fork() and keep the child alive until we're done. Note that + * we expect the pinned page to not get shared with the child. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto unregister_buffers; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + } else { + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto unregister_buffers; + } + } + + /* + * Modify the page and write page content as observed by the fixed + * buffer pin to the file so we can verify it. + */ + memset(mem, 0xff, size); + sqe = io_uring_get_sqe(&ring); + if (!sqe) { + ksft_test_result_fail("io_uring_get_sqe() failed\n"); + goto quit_child; + } + io_uring_prep_write_fixed(sqe, fd, mem, size, 0, 0); + + ret = io_uring_submit(&ring); + if (ret < 0) { + ksft_test_result_fail("io_uring_submit() failed\n"); + goto quit_child; + } + + ret = io_uring_wait_cqe(&ring, &cqe); + if (ret < 0) { + ksft_test_result_fail("io_uring_wait_cqe() failed\n"); + goto quit_child; + } + + if (cqe->res != size) { + ksft_test_result_fail("write_fixed failed\n"); + goto quit_child; + } + io_uring_cqe_seen(&ring, cqe); + + /* Read back the file content to the temporary buffer. */ + total = 0; + while (total < size) { + cur = pread(fd, tmp + total, size - total, total); + if (cur < 0) { + ksft_test_result_fail("pread() failed\n"); + goto quit_child; + } + total += cur; + } + + /* Finally, check if we read what we expected. */ + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/W pin is reliable\n"); + +quit_child: + if (use_fork) { + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + } +unregister_buffers: + io_uring_unregister_buffers(&ring); +queue_exit: + io_uring_queue_exit(&ring); +free_tmp: + free(tmp); +close_file: + fclose(file); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_iouring_ro(char *mem, size_t size) +{ + do_test_iouring(mem, size, false); +} + +static void test_iouring_fork(char *mem, size_t size) +{ + do_test_iouring(mem, size, true); +} + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + +enum ro_pin_test { + RO_PIN_TEST, + RO_PIN_TEST_SHARED, + RO_PIN_TEST_PREVIOUSLY_SHARED, + RO_PIN_TEST_RO_EXCLUSIVE, +}; + +static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, + bool fast) +{ + struct pin_longterm_test args; + struct comm_pipes comm_pipes; + char *tmp, buf; + __u64 tmp_val; + int ret; + + if (gup_fd < 0) { + ksft_test_result_skip("gup_test not available\n"); + return; + } + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + return; + } + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free_tmp; + } + + switch (test) { + case RO_PIN_TEST: + break; + case RO_PIN_TEST_SHARED: + case RO_PIN_TEST_PREVIOUSLY_SHARED: + /* + * Share the pages with our child. As the pages are not pinned, + * this should just work. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + /* Wait until our child is ready. */ + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + + if (test == RO_PIN_TEST_PREVIOUSLY_SHARED) { + /* + * Tell the child to quit now and wait until it quit. + * The pages should now be mapped R/O into our page + * tables, but they are no longer shared. + */ + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + } + break; + case RO_PIN_TEST_RO_EXCLUSIVE: + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto close_comm_pipes; + } + break; + default: + assert(false); + } + + /* Take a R/O pin. This should trigger unsharing. */ + args.addr = (__u64)(uintptr_t)mem; + args.size = size; + args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args); + if (ret) { + if (errno == EINVAL) + ksft_test_result_skip("PIN_LONGTERM_TEST_START failed\n"); + else + ksft_test_result_fail("PIN_LONGTERM_TEST_START failed\n"); + goto wait; + } + + /* Modify the page. */ + memset(mem, 0xff, size); + + /* + * Read back the content via the pin to the temporary buffer and + * test if we observed the modification. + */ + tmp_val = (__u64)(uintptr_t)tmp; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val); + if (ret) + ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n"); + else + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/O pin is reliable\n"); + + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_STOP); + if (ret) + ksft_print_msg("[INFO] PIN_LONGTERM_TEST_STOP failed\n"); +wait: + switch (test) { + case RO_PIN_TEST_SHARED: + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + break; + default: + break; + } +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free_tmp: + free(tmp); +} + +static void test_ro_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, false); +} + +static void test_ro_fast_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, true); +} + +static void test_ro_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, false); +} + +static void test_ro_fast_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, true); +} + +static void test_ro_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, false); +} + +static void test_ro_fast_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, true); +} + +typedef void (*test_fn)(char *mem, size_t size); + +static void do_run_with_base_page(test_fn fn, bool swapout) +{ + char *mem; + int ret; + + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + ret = madvise(mem, pagesize, MADV_NOHUGEPAGE); + /* Ignore if not around on a kernel. */ + if (ret && errno != EINVAL) { + ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); + goto munmap; + } + + /* Populate a base page. */ + memset(mem, 0, pagesize); + + if (swapout) { + madvise(mem, pagesize, MADV_PAGEOUT); + if (!pagemap_is_swapped(pagemap_fd, mem)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + } + + fn(mem, pagesize); +munmap: + munmap(mem, pagesize); +} + +static void run_with_base_page(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with base page\n", desc); + do_run_with_base_page(fn, false); +} + +static void run_with_base_page_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped out base page\n", desc); + do_run_with_base_page(fn, true); +} + +enum thp_run { + THP_RUN_PMD, + THP_RUN_PMD_SWAPOUT, + THP_RUN_PTE, + THP_RUN_PTE_SWAPOUT, + THP_RUN_SINGLE_PTE, + THP_RUN_SINGLE_PTE_SWAPOUT, + THP_RUN_PARTIAL_MREMAP, + THP_RUN_PARTIAL_SHARED, +}; + +static void do_run_with_thp(test_fn fn, enum thp_run thp_run) +{ + char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; + size_t size, mmap_size, mremap_size; + int ret; + + /* For alignment purposes, we need twice the thp size. */ + mmap_size = 2 * thpsize; + mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + /* We need a THP-aligned memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + + ret = madvise(mem, thpsize, MADV_HUGEPAGE); + if (ret) { + ksft_test_result_fail("MADV_HUGEPAGE failed\n"); + goto munmap; + } + + /* + * Try to populate a THP. Touch the first sub-page and test if we get + * another sub-page populated automatically. + */ + mem[0] = 0; + if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + memset(mem, 0, thpsize); + + size = thpsize; + switch (thp_run) { + case THP_RUN_PMD: + case THP_RUN_PMD_SWAPOUT: + break; + case THP_RUN_PTE: + case THP_RUN_PTE_SWAPOUT: + /* + * Trigger PTE-mapping the THP by temporarily mapping a single + * subpage R/O. + */ + ret = mprotect(mem + pagesize, pagesize, PROT_READ); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + break; + case THP_RUN_SINGLE_PTE: + case THP_RUN_SINGLE_PTE_SWAPOUT: + /* + * Discard all but a single subpage of that PTE-mapped THP. What + * remains is a single PTE mapping a single subpage. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED); + if (ret) { + ksft_test_result_fail("MADV_DONTNEED failed\n"); + goto munmap; + } + size = pagesize; + break; + case THP_RUN_PARTIAL_MREMAP: + /* + * Remap half of the THP. We need some new memory location + * for that. + */ + mremap_size = thpsize / 2; + mremap_mem = mmap(NULL, mremap_size, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + tmp = mremap(mem + mremap_size, mremap_size, mremap_size, + MREMAP_MAYMOVE | MREMAP_FIXED, mremap_mem); + if (tmp != mremap_mem) { + ksft_test_result_fail("mremap() failed\n"); + goto munmap; + } + size = mremap_size; + break; + case THP_RUN_PARTIAL_SHARED: + /* + * Share the first page of the THP with a child and quit the + * child. This will result in some parts of the THP never + * have been shared. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK); + if (ret) { + ksft_test_result_fail("MADV_DONTFORK failed\n"); + goto munmap; + } + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto munmap; + } else if (!ret) { + exit(0); + } + wait(&ret); + /* Allow for sharing all pages again. */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK); + if (ret) { + ksft_test_result_fail("MADV_DOFORK failed\n"); + goto munmap; + } + break; + default: + assert(false); + } + + switch (thp_run) { + case THP_RUN_PMD_SWAPOUT: + case THP_RUN_PTE_SWAPOUT: + case THP_RUN_SINGLE_PTE_SWAPOUT: + madvise(mem, size, MADV_PAGEOUT); + if (!range_is_swapped(mem, size)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + break; + default: + break; + } + + fn(mem, size); +munmap: + munmap(mmap_mem, mmap_size); + if (mremap_mem != MAP_FAILED) + munmap(mremap_mem, mremap_size); +} + +static void run_with_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD); +} + +static void run_with_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT); +} + +static void run_with_pte_mapped_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE); +} + +static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT); +} + +static void run_with_single_pte_of_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE); +} + +static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT); +} + +static void run_with_partial_mremap_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP); +} + +static void run_with_partial_shared_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); +} + +static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize) +{ + int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB; + char *mem, *dummy; + + ksft_print_msg("[RUN] %s ... with hugetlb (%zu kB)\n", desc, + hugetlbsize / 1024); + + flags |= __builtin_ctzll(hugetlbsize) << MAP_HUGE_SHIFT; + + mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + return; + } + + /* Populate an huge page. */ + memset(mem, 0, hugetlbsize); + + /* + * We need a total of two hugetlb pages to handle COW/unsharing + * properly, otherwise we might get zapped by a SIGBUS. + */ + dummy = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (dummy == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + goto munmap; + } + munmap(dummy, hugetlbsize); + + fn(mem, hugetlbsize); +munmap: + munmap(mem, hugetlbsize); +} + +struct test_case { + const char *desc; + test_fn fn; +}; + +/* + * Test cases that are specific to anonymous pages: pages in private mappings + * that may get shared via COW during fork(). + */ +static const struct test_case anon_test_cases[] = { + /* + * Basic COW tests for fork() without any GUP. If we miss to break COW, + * either the child can observe modifications by the parent or the + * other way around. + */ + { + "Basic COW after fork()", + test_cow_in_parent, + }, + /* + * Basic test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "Basic COW after fork() with mprotect() optimization", + test_cow_in_parent_mprotect, + }, + /* + * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If + * we miss to break COW, the child observes modifications by the parent. + * This is CVE-2020-29374 reported by Jann Horn. + */ + { + "vmsplice() + unmap in child", + test_vmsplice_in_child + }, + /* + * vmsplice() test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "vmsplice() + unmap in child with mprotect() optimization", + test_vmsplice_in_child_mprotect + }, + /* + * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after + * fork(); modify in the child. If we miss to break COW, the parent + * observes modifications by the child. + */ + { + "vmsplice() before fork(), unmap in parent after fork()", + test_vmsplice_before_fork, + }, + /* + * vmsplice() [R/O GUP] + unmap in parent after fork(); modify in the + * child. If we miss to break COW, the parent observes modifications by + * the child. + */ + { + "vmsplice() + unmap in parent after fork()", + test_vmsplice_after_fork, + }, +#ifdef LOCAL_CONFIG_HAVE_LIBURING + /* + * Take a R/W longterm pin and then map the page R/O into the page + * table to trigger a write fault on next access. When modifying the + * page, the page content must be visible via the pin. + */ + { + "R/O-mapping a page registered as iouring fixed buffer", + test_iouring_ro, + }, + /* + * Take a R/W longterm pin and then fork() a child. When modifying the + * page, the page content must be visible via the pin. We expect the + * pinned page to not get shared with the child. + */ + { + "fork() with an iouring fixed buffer", + test_iouring_fork, + }, + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + /* + * Take a R/O longterm pin on a R/O-mapped shared anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped shared page", + test_ro_pin_on_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped shared page", + test_ro_fast_pin_on_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page that + * was previously shared. When modifying the page via the page table, + * the page content change must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped previously-shared page", + test_ro_pin_on_ro_previously_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped previously-shared page", + test_ro_fast_pin_on_ro_previously_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped exclusive page", + test_ro_pin_on_ro_exclusive, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped exclusive page", + test_ro_fast_pin_on_ro_exclusive, + }, +}; + +static void run_anon_test_case(struct test_case const *test_case) +{ + int i; + + run_with_base_page(test_case->fn, test_case->desc); + run_with_base_page_swap(test_case->fn, test_case->desc); + if (thpsize) { + run_with_thp(test_case->fn, test_case->desc); + run_with_thp_swap(test_case->fn, test_case->desc); + run_with_pte_mapped_thp(test_case->fn, test_case->desc); + run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc); + run_with_single_pte_of_thp(test_case->fn, test_case->desc); + run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc); + run_with_partial_mremap_thp(test_case->fn, test_case->desc); + run_with_partial_shared_thp(test_case->fn, test_case->desc); + } + for (i = 0; i < nr_hugetlbsizes; i++) + run_with_hugetlb(test_case->fn, test_case->desc, + hugetlbsizes[i]); +} + +static void run_anon_test_cases(void) +{ + int i; + + ksft_print_msg("[INFO] Anonymous memory tests in private mappings\n"); + + for (i = 0; i < ARRAY_SIZE(anon_test_cases); i++) + run_anon_test_case(&anon_test_cases[i]); +} + +static int tests_per_anon_test_case(void) +{ + int tests = 2 + nr_hugetlbsizes; + + if (thpsize) + tests += 8; + return tests; +} + +typedef void (*non_anon_test_fn)(char *mem, const char *smem, size_t size); + +static void test_cow(char *mem, const char *smem, size_t size) +{ + char *old = malloc(size); + + /* Backup the original content. */ + memcpy(old, smem, size); + + /* Modify the page. */ + memset(mem, 0xff, size); + + /* See if we still read the old values via the other mapping. */ + ksft_test_result(!memcmp(smem, old, size), + "Other mapping not modified\n"); + free(old); +} + +static void test_ro_pin(char *mem, const char *smem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST, false); +} + +static void test_ro_fast_pin(char *mem, const char *smem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST, true); +} + +static void run_with_zeropage(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + + ksft_print_msg("[RUN] %s ... with shared zeropage\n", desc); + + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANON, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + smem = mmap(NULL, pagesize, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Read from the page to populate the shared zeropage. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +} + +static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, *mmap_mem, *mmap_smem, tmp; + size_t mmap_size; + int ret; + + ksft_print_msg("[RUN] %s ... with huge zeropage\n", desc); + + if (!has_huge_zeropage) { + ksft_test_result_skip("Huge zeropage not enabled\n"); + return; + } + + /* For alignment purposes, we need twice the thp size. */ + mmap_size = 2 * thpsize; + mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + mmap_smem = mmap(NULL, mmap_size, PROT_READ, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_smem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* We need a THP-aligned memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + smem = (char *)(((uintptr_t)mmap_smem + thpsize) & ~(thpsize - 1)); + + ret = madvise(mem, thpsize, MADV_HUGEPAGE); + ret |= madvise(smem, thpsize, MADV_HUGEPAGE); + if (ret) { + ksft_test_result_fail("MADV_HUGEPAGE failed\n"); + goto munmap; + } + + /* + * Read from the memory to populate the huge shared zeropage. Read from + * the first sub-page and test if we get another sub-page populated + * automatically. + */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + if (!pagemap_is_populated(pagemap_fd, mem + pagesize) || + !pagemap_is_populated(pagemap_fd, smem + pagesize)) { + ksft_test_result_skip("Did not get THPs populated\n"); + goto munmap; + } + + fn(mem, smem, thpsize); +munmap: + munmap(mmap_mem, mmap_size); + if (mmap_smem != MAP_FAILED) + munmap(mmap_smem, mmap_size); +} + +static void run_with_memfd(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + int fd; + + ksft_print_msg("[RUN] %s ... with memfd\n", desc); + + fd = memfd_create("test", 0); + if (fd < 0) { + ksft_test_result_fail("memfd_create() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, pagesize)) { + ksft_test_result_fail("fallocate() failed\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto close; + } + smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +close: + close(fd); +} + +static void run_with_tmpfile(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + FILE *file; + int fd; + + ksft_print_msg("[RUN] %s ... with tmpfile\n", desc); + + file = tmpfile(); + if (!file) { + ksft_test_result_fail("tmpfile() failed\n"); + return; + } + + fd = fileno(file); + if (fd < 0) { + ksft_test_result_skip("fileno() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, pagesize)) { + ksft_test_result_fail("fallocate() failed\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto close; + } + smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +close: + fclose(file); +} + +static void run_with_memfd_hugetlb(non_anon_test_fn fn, const char *desc, + size_t hugetlbsize) +{ + int flags = MFD_HUGETLB; + char *mem, *smem, tmp; + int fd; + + ksft_print_msg("[RUN] %s ... with memfd hugetlb (%zu kB)\n", desc, + hugetlbsize / 1024); + + flags |= __builtin_ctzll(hugetlbsize) << MFD_HUGE_SHIFT; + + fd = memfd_create("test", flags); + if (fd < 0) { + ksft_test_result_skip("memfd_create() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, hugetlbsize)) { + ksft_test_result_skip("need more free huge pages\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, + 0); + if (mem == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + goto close; + } + smem = mmap(NULL, hugetlbsize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, hugetlbsize); +munmap: + munmap(mem, hugetlbsize); + if (mem != MAP_FAILED) + munmap(smem, hugetlbsize); +close: + close(fd); +} + +struct non_anon_test_case { + const char *desc; + non_anon_test_fn fn; +}; + +/* + * Test cases that target any pages in private mappings that are not anonymous: + * pages that may get shared via COW ndependent of fork(). This includes + * the shared zeropage(s), pagecache pages, ... + */ +static const struct non_anon_test_case non_anon_test_cases[] = { + /* + * Basic COW test without any GUP. If we miss to break COW, changes are + * visible via other private/shared mappings. + */ + { + "Basic COW", + test_cow, + }, + /* + * Take a R/O longterm pin. When modifying the page via the page table, + * the page content change must be visible via the pin. + */ + { + "R/O longterm GUP pin", + test_ro_pin, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O longterm GUP-fast pin", + test_ro_fast_pin, + }, +}; + +static void run_non_anon_test_case(struct non_anon_test_case const *test_case) +{ + int i; + + run_with_zeropage(test_case->fn, test_case->desc); + run_with_memfd(test_case->fn, test_case->desc); + run_with_tmpfile(test_case->fn, test_case->desc); + if (thpsize) + run_with_huge_zeropage(test_case->fn, test_case->desc); + for (i = 0; i < nr_hugetlbsizes; i++) + run_with_memfd_hugetlb(test_case->fn, test_case->desc, + hugetlbsizes[i]); +} + +static void run_non_anon_test_cases(void) +{ + int i; + + ksft_print_msg("[RUN] Non-anonymous memory tests in private mappings\n"); + + for (i = 0; i < ARRAY_SIZE(non_anon_test_cases); i++) + run_non_anon_test_case(&non_anon_test_cases[i]); +} + +static int tests_per_non_anon_test_case(void) +{ + int tests = 3 + nr_hugetlbsizes; + + if (thpsize) + tests += 1; + return tests; +} + +int main(int argc, char **argv) +{ + int err; + + pagesize = getpagesize(); + detect_thpsize(); + detect_hugetlbsizes(); + detect_huge_zeropage(); + + ksft_print_header(); + ksft_set_plan(ARRAY_SIZE(anon_test_cases) * tests_per_anon_test_case() + + ARRAY_SIZE(non_anon_test_cases) * tests_per_non_anon_test_case()); + + gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR); + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_msg("opening pagemap failed\n"); + + run_anon_test_cases(); + run_non_anon_test_cases(); + + err = ksft_get_fail_cnt(); + if (err) + ksft_exit_fail_msg("%d out of %d tests failed\n", + err, ksft_test_num()); + return ksft_exit_pass(); +} -- cgit v1.2.3