From 30e920e1debb437e5aea7a4ccdab61634354297a Mon Sep 17 00:00:00 2001 From: Ankit Agrawal Date: Tue, 20 Feb 2024 17:20:54 +0530 Subject: vfio/pci: rename and export range_intersect_range range_intersect_range determines an overlap between two ranges. If an overlap, the helper function returns the overlapping offset and size. The VFIO PCI variant driver emulates the PCI config space BAR offset registers. These offset may be accessed for read/write with a variety of lengths including sub-word sizes from sub-word offsets. The driver makes use of this helper function to read/write the targeted part of the emulated register. Make this a vfio_pci_core function, rename and export as GPL. Also update references in virtio driver. Reviewed-by: Kevin Tian Reviewed-by: Yishai Hadas Signed-off-by: Ankit Agrawal Link: https://lore.kernel.org/r/20240220115055.23546-3-ankita@nvidia.com Signed-off-by: Alex Williamson --- drivers/vfio/pci/virtio/main.c | 72 +++++++++++++++--------------------------- 1 file changed, 26 insertions(+), 46 deletions(-) (limited to 'drivers/vfio/pci/virtio/main.c') diff --git a/drivers/vfio/pci/virtio/main.c b/drivers/vfio/pci/virtio/main.c index d5af683837d3..b5d3a8c5bbc9 100644 --- a/drivers/vfio/pci/virtio/main.c +++ b/drivers/vfio/pci/virtio/main.c @@ -132,33 +132,6 @@ end: return ret ? ret : count; } -static bool range_intersect_range(loff_t range1_start, size_t count1, - loff_t range2_start, size_t count2, - loff_t *start_offset, - size_t *intersect_count, - size_t *register_offset) -{ - if (range1_start <= range2_start && - range1_start + count1 > range2_start) { - *start_offset = range2_start - range1_start; - *intersect_count = min_t(size_t, count2, - range1_start + count1 - range2_start); - *register_offset = 0; - return true; - } - - if (range1_start > range2_start && - range1_start < range2_start + count2) { - *start_offset = 0; - *intersect_count = min_t(size_t, count1, - range2_start + count2 - range1_start); - *register_offset = range1_start - range2_start; - return true; - } - - return false; -} - static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, char __user *buf, size_t count, loff_t *ppos) @@ -178,16 +151,18 @@ static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, if (ret < 0) return ret; - if (range_intersect_range(pos, count, PCI_DEVICE_ID, sizeof(val16), - ©_offset, ©_count, ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_DEVICE_ID, + sizeof(val16), ©_offset, + ©_count, ®ister_offset)) { val16 = cpu_to_le16(VIRTIO_TRANS_ID_NET); if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, copy_count)) return -EFAULT; } if ((le16_to_cpu(virtvdev->pci_cmd) & PCI_COMMAND_IO) && - range_intersect_range(pos, count, PCI_COMMAND, sizeof(val16), - ©_offset, ©_count, ®ister_offset)) { + vfio_pci_core_range_intersect_range(pos, count, PCI_COMMAND, + sizeof(val16), ©_offset, + ©_count, ®ister_offset)) { if (copy_from_user((void *)&val16 + register_offset, buf + copy_offset, copy_count)) return -EFAULT; @@ -197,16 +172,18 @@ static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, return -EFAULT; } - if (range_intersect_range(pos, count, PCI_REVISION_ID, sizeof(val8), - ©_offset, ©_count, ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_REVISION_ID, + sizeof(val8), ©_offset, + ©_count, ®ister_offset)) { /* Transional needs to have revision 0 */ val8 = 0; if (copy_to_user(buf + copy_offset, &val8, copy_count)) return -EFAULT; } - if (range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, sizeof(val32), - ©_offset, ©_count, ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, + sizeof(val32), ©_offset, + ©_count, ®ister_offset)) { u32 bar_mask = ~(virtvdev->bar0_virtual_buf_size - 1); u32 pci_base_addr_0 = le32_to_cpu(virtvdev->pci_base_addr_0); @@ -215,8 +192,9 @@ static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, return -EFAULT; } - if (range_intersect_range(pos, count, PCI_SUBSYSTEM_ID, sizeof(val16), - ©_offset, ©_count, ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_SUBSYSTEM_ID, + sizeof(val16), ©_offset, + ©_count, ®ister_offset)) { /* * Transitional devices use the PCI subsystem device id as * virtio device id, same as legacy driver always did. @@ -227,8 +205,9 @@ static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, return -EFAULT; } - if (range_intersect_range(pos, count, PCI_SUBSYSTEM_VENDOR_ID, sizeof(val16), - ©_offset, ©_count, ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_SUBSYSTEM_VENDOR_ID, + sizeof(val16), ©_offset, + ©_count, ®ister_offset)) { val16 = cpu_to_le16(PCI_VENDOR_ID_REDHAT_QUMRANET); if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, copy_count)) @@ -270,19 +249,20 @@ static ssize_t virtiovf_pci_write_config(struct vfio_device *core_vdev, loff_t copy_offset; size_t copy_count; - if (range_intersect_range(pos, count, PCI_COMMAND, sizeof(virtvdev->pci_cmd), - ©_offset, ©_count, - ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_COMMAND, + sizeof(virtvdev->pci_cmd), + ©_offset, ©_count, + ®ister_offset)) { if (copy_from_user((void *)&virtvdev->pci_cmd + register_offset, buf + copy_offset, copy_count)) return -EFAULT; } - if (range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, - sizeof(virtvdev->pci_base_addr_0), - ©_offset, ©_count, - ®ister_offset)) { + if (vfio_pci_core_range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, + sizeof(virtvdev->pci_base_addr_0), + ©_offset, ©_count, + ®ister_offset)) { if (copy_from_user((void *)&virtvdev->pci_base_addr_0 + register_offset, buf + copy_offset, copy_count)) -- cgit v1.2.3