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The library will be used in the upcoming test patch to configure the VFs for a given PF device. Opportunistically, move vfio_pci_get_group_from_dev() to this library as it falls under the same bucket. Rename it to sysfs_iommu_group_get() to align with other function names. Signed-off-by: Raghavendra Rao Ananta --- .../selftests/vfio/lib/include/libvfio.h | 1 + .../vfio/lib/include/libvfio/sysfs.h | 12 ++ tools/testing/selftests/vfio/lib/libvfio.mk | 1 + tools/testing/selftests/vfio/lib/sysfs.c | 136 ++++++++++++++++++ .../selftests/vfio/lib/vfio_pci_device.c | 22 +-- 5 files changed, 151 insertions(+), 21 deletions(-) create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/sysfs.h create mode 100644 tools/testing/selftests/vfio/lib/sysfs.c diff --git a/tools/testing/selftests/vfio/lib/include/libvfio.h b/tools/tes= ting/selftests/vfio/lib/include/libvfio.h index 279ddcd70194..bbe1d7616a64 100644 --- a/tools/testing/selftests/vfio/lib/include/libvfio.h +++ b/tools/testing/selftests/vfio/lib/include/libvfio.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include =20 diff --git a/tools/testing/selftests/vfio/lib/include/libvfio/sysfs.h b/too= ls/testing/selftests/vfio/lib/include/libvfio/sysfs.h new file mode 100644 index 000000000000..c48d5ef00ba6 --- /dev/null +++ b/tools/testing/selftests/vfio/lib/include/libvfio/sysfs.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef SELFTESTS_VFIO_LIB_INCLUDE_LIBVFIO_SYSFS_H +#define SELFTESTS_VFIO_LIB_INCLUDE_LIBVFIO_SYSFS_H + +int sysfs_sriov_totalvfs_get(const char *bdf); +int sysfs_sriov_numvfs_get(const char *bdf); +void sysfs_sriov_numvfs_set(const char *bdfs, int numvfs); +char *sysfs_sriov_vf_bdf_get(const char *pf_bdf, int i); +unsigned int sysfs_iommu_group_get(const char *bdf); +char *sysfs_driver_get(const char *bdf); + +#endif /* SELFTESTS_VFIO_LIB_INCLUDE_LIBVFIO_SYSFS_H */ diff --git a/tools/testing/selftests/vfio/lib/libvfio.mk b/tools/testing/se= lftests/vfio/lib/libvfio.mk index 9f47bceed16f..b7857319c3f1 100644 --- a/tools/testing/selftests/vfio/lib/libvfio.mk +++ b/tools/testing/selftests/vfio/lib/libvfio.mk @@ -6,6 +6,7 @@ LIBVFIO_SRCDIR :=3D $(selfdir)/vfio/lib LIBVFIO_C :=3D iommu.c LIBVFIO_C +=3D iova_allocator.c LIBVFIO_C +=3D libvfio.c +LIBVFIO_C +=3D sysfs.c LIBVFIO_C +=3D vfio_pci_device.c LIBVFIO_C +=3D vfio_pci_driver.c =20 diff --git a/tools/testing/selftests/vfio/lib/sysfs.c b/tools/testing/selft= ests/vfio/lib/sysfs.c new file mode 100644 index 000000000000..f01598ff15d7 --- /dev/null +++ b/tools/testing/selftests/vfio/lib/sysfs.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include + +#include + +static int sysfs_val_get(const char *component, const char *name, + const char *file) +{ + char path[PATH_MAX]; + char buf[32]; + int fd; + + snprintf_assert(path, PATH_MAX, "/sys/bus/pci/%s/%s/%s", component, name,= file); + fd =3D open(path, O_RDONLY); + if (fd < 0) + return fd; + + VFIO_ASSERT_GT(read(fd, buf, ARRAY_SIZE(buf)), 0); + VFIO_ASSERT_EQ(close(fd), 0); + + return strtol(buf, NULL, 0); +} + +static void sysfs_val_set(const char *component, const char *name, + const char *file, const char *val) +{ + char path[PATH_MAX]; + int fd; + + snprintf_assert(path, PATH_MAX, "/sys/bus/pci/%s/%s/%s", component, name,= file); + VFIO_ASSERT_GT(fd =3D open(path, O_WRONLY), 0); + + VFIO_ASSERT_EQ(write(fd, val, strlen(val)), strlen(val)); + VFIO_ASSERT_EQ(close(fd), 0); +} + +static int sysfs_device_val_get(const char *bdf, const char *file) +{ + return sysfs_val_get("devices", bdf, file); +} + +static void sysfs_device_val_set(const char *bdf, const char *file, const = char *val) +{ + sysfs_val_set("devices", bdf, file, val); +} + +static void sysfs_device_val_set_int(const char *bdf, const char *file, in= t val) +{ + char val_str[32]; + + snprintf_assert(val_str, sizeof(val_str), "%d", val); + sysfs_device_val_set(bdf, file, val_str); +} + +int sysfs_sriov_totalvfs_get(const char *bdf) +{ + return sysfs_device_val_get(bdf, "sriov_totalvfs"); +} + +int sysfs_sriov_numvfs_get(const char *bdf) +{ + return sysfs_device_val_get(bdf, "sriov_numvfs"); +} + +void sysfs_sriov_numvfs_set(const char *bdf, int numvfs) +{ + sysfs_device_val_set_int(bdf, "sriov_numvfs", numvfs); +} + +char *sysfs_sriov_vf_bdf_get(const char *pf_bdf, int i) +{ + char vf_path[PATH_MAX]; + char path[PATH_MAX]; + char *out_vf_bdf; + int ret; + + out_vf_bdf =3D calloc(16, sizeof(char)); + VFIO_ASSERT_NOT_NULL(out_vf_bdf); + + snprintf_assert(path, PATH_MAX, "/sys/bus/pci/devices/%s/virtfn%d", pf_bd= f, i); + + ret =3D readlink(path, vf_path, PATH_MAX); + VFIO_ASSERT_NE(ret, -1); + + ret =3D sscanf(basename(vf_path), "%s", out_vf_bdf); + VFIO_ASSERT_EQ(ret, 1); + + return out_vf_bdf; +} + +unsigned int sysfs_iommu_group_get(const char *bdf) +{ + char dev_iommu_group_path[PATH_MAX]; + char path[PATH_MAX]; + unsigned int group; + int ret; + + snprintf_assert(path, PATH_MAX, "/sys/bus/pci/devices/%s/iommu_group", bd= f); + + ret =3D readlink(path, dev_iommu_group_path, sizeof(dev_iommu_group_path)= ); + VFIO_ASSERT_NE(ret, -1, "Failed to get the IOMMU group for device: %s\n",= bdf); + + ret =3D sscanf(basename(dev_iommu_group_path), "%u", &group); + VFIO_ASSERT_EQ(ret, 1, "Failed to get the IOMMU group for device: %s\n", = bdf); + + return group; +} + +char *sysfs_driver_get(const char *bdf) +{ + char driver_path[PATH_MAX]; + char path[PATH_MAX]; + char *out_driver; + int ret; + + out_driver =3D calloc(64, sizeof(char)); + VFIO_ASSERT_NOT_NULL(out_driver); + + snprintf_assert(path, PATH_MAX, "/sys/bus/pci/devices/%s/driver", bdf); + ret =3D readlink(path, driver_path, PATH_MAX); + if (ret =3D=3D -1) { + free(out_driver); + + if (errno =3D=3D ENOENT) + return NULL; + + VFIO_FAIL("Failed to read %s\n", path); + } + + strcpy(out_driver, basename(driver_path)); + return out_driver; +} diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/tes= ting/selftests/vfio/lib/vfio_pci_device.c index 64a19481b734..a7e00d017fc6 100644 --- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c +++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c @@ -22,8 +22,6 @@ #include "../../../kselftest.h" #include =20 -#define PCI_SYSFS_PATH "/sys/bus/pci/devices" - static void vfio_pci_irq_set(struct vfio_pci_device *device, u32 index, u32 vector, u32 count, int *fds) { @@ -181,24 +179,6 @@ void vfio_pci_device_reset(struct vfio_pci_device *dev= ice) ioctl_assert(device->fd, VFIO_DEVICE_RESET, NULL); } =20 -static unsigned int vfio_pci_get_group_from_dev(const char *bdf) -{ - char dev_iommu_group_path[PATH_MAX] =3D {0}; - char sysfs_path[PATH_MAX] =3D {0}; - unsigned int group; - int ret; - - snprintf_assert(sysfs_path, PATH_MAX, "%s/%s/iommu_group", PCI_SYSFS_PATH= , bdf); - - ret =3D readlink(sysfs_path, dev_iommu_group_path, sizeof(dev_iommu_group= _path)); - VFIO_ASSERT_NE(ret, -1, "Failed to get the IOMMU group for device: %s\n",= bdf); - - ret =3D sscanf(basename(dev_iommu_group_path), "%u", &group); - VFIO_ASSERT_EQ(ret, 1, "Failed to get the IOMMU group for device: %s\n", = bdf); - - return group; -} - static void vfio_pci_group_setup(struct vfio_pci_device *device, const cha= r *bdf) { struct vfio_group_status group_status =3D { @@ -207,7 +187,7 @@ static void vfio_pci_group_setup(struct vfio_pci_device= *device, const char *bdf char group_path[32]; int group; =20 - group =3D vfio_pci_get_group_from_dev(bdf); + group =3D sysfs_iommu_group_get(bdf); snprintf_assert(group_path, sizeof(group_path), "/dev/vfio/%d", group); =20 device->group_fd =3D open(group_path, O_RDWR); --=20 2.53.0.rc2.204.g2597b5adb4-goog