From: Manish Honap <[email protected]> Region Management makes use of APIs provided by CXL_CORE as below:
CREATE_REGION flow: 1. Validate request (size, decoder availability) 2. Allocate HPA via cxl_get_hpa_freespace() 3. Allocate DPA via cxl_request_dpa() 4. Create region via cxl_create_region() - commits HDM decoder 5. Get HPA range via cxl_get_region_range() DESTROY_REGION flow: 1. Detach decoder via cxl_decoder_detach() 2. Free DPA via cxl_dpa_free() 3. Release root decoder via cxl_put_root_decoder() Use DEFINE_FREE scope helpers so error paths unwind cleanly. Signed-off-by: Manish Honap <[email protected]> --- drivers/vfio/pci/cxl/vfio_cxl_core.c | 119 +++++++++++++++++++++++++++ drivers/vfio/pci/cxl/vfio_cxl_priv.h | 8 ++ 2 files changed, 127 insertions(+) diff --git a/drivers/vfio/pci/cxl/vfio_cxl_core.c b/drivers/vfio/pci/cxl/vfio_cxl_core.c index 02755265d530..30b365b91903 100644 --- a/drivers/vfio/pci/cxl/vfio_cxl_core.c +++ b/drivers/vfio/pci/cxl/vfio_cxl_core.c @@ -21,6 +21,13 @@ #include "../vfio_pci_priv.h" #include "vfio_cxl_priv.h" +/* + * Scope-based cleanup wrappers for the CXL resource APIs + */ +DEFINE_FREE(cxl_put_root_decoder, struct cxl_root_decoder *, if (!IS_ERR_OR_NULL(_T)) cxl_put_root_decoder(_T)) +DEFINE_FREE(cxl_dpa_free, struct cxl_endpoint_decoder *, if (!IS_ERR_OR_NULL(_T)) cxl_dpa_free(_T)) +DEFINE_FREE(cxl_unregister_region, struct cxl_region *, if (!IS_ERR_OR_NULL(_T)) cxl_unregister_region(_T)) + /* * vfio_cxl_create_device_state - Allocate and validate CXL device state * @@ -165,6 +172,112 @@ static int vfio_cxl_setup_regs(struct vfio_pci_core_device *vdev, return ret; } +int vfio_cxl_create_cxl_region(struct vfio_pci_cxl_state *cxl, + resource_size_t size) +{ + resource_size_t max_size; + + WARN_ON(cxl->precommitted); + + struct cxl_root_decoder *cxlrd __free(cxl_put_root_decoder) = + cxl_get_hpa_freespace(cxl->cxlmd, 1, + CXL_DECODER_F_RAM | CXL_DECODER_F_TYPE2, + &max_size); + if (IS_ERR(cxlrd)) + return PTR_ERR(cxlrd); + + /* Insufficient HPA space; cxlrd freed automatically by __free() */ + if (max_size < size) + return -ENOSPC; + + struct cxl_endpoint_decoder *cxled __free(cxl_dpa_free) = + cxl_request_dpa(cxl->cxlmd, CXL_PARTMODE_RAM, size); + if (IS_ERR(cxled)) + return PTR_ERR(cxled); + + struct cxl_region *region __free(cxl_unregister_region) = + cxl_create_region(cxlrd, &cxled, 1); + if (IS_ERR(region)) + return PTR_ERR(region); + + /* All operations succeeded; transfer ownership to cxl state */ + cxl->cxlrd = no_free_ptr(cxlrd); + cxl->cxled = no_free_ptr(cxled); + cxl->region = no_free_ptr(region); + + return 0; +} + +void vfio_cxl_destroy_cxl_region(struct vfio_pci_cxl_state *cxl) +{ + if (!cxl->region) + return; + + cxl_unregister_region(cxl->region); + cxl->region = NULL; + + if (!cxl->precommitted) { + cxl_dpa_free(cxl->cxled); + cxl_put_root_decoder(cxl->cxlrd); + } + + cxl->cxled = NULL; + cxl->cxlrd = NULL; +} + +static int vfio_cxl_create_region_helper(struct vfio_pci_core_device *vdev, + struct vfio_pci_cxl_state *cxl, + resource_size_t capacity) +{ + struct pci_dev *pdev = vdev->pdev; + struct range range; + int ret; + + if (cxl->precommitted) { + struct cxl_endpoint_decoder *cxled; + struct cxl_region *region; + + cxled = cxl_get_committed_decoder(cxl->cxlmd, ®ion); + if (IS_ERR(cxled)) + return PTR_ERR(cxled); + cxl->cxled = cxled; + cxl->region = region; + } else { + ret = vfio_cxl_create_cxl_region(cxl, capacity); + if (ret) + return ret; + } + + if (!cxl->region) { + pci_err(pdev, "Failed to create CXL region\n"); + ret = -ENODEV; + goto failed; + } + + ret = cxl_get_region_range(cxl->region, &range); + if (ret) + goto failed; + + cxl->region_hpa = range.start; + cxl->region_size = range_len(&range); + + pci_dbg(pdev, "CXL region: HPA 0x%llx size %lu MB\n", + cxl->region_hpa, cxl->region_size >> 20); + + return 0; + +failed: + if (cxl->region) { + cxl_unregister_region(cxl->region); + cxl->region = NULL; + } + + cxl->cxled = NULL; + cxl->cxlrd = NULL; + + return ret; +} + static int vfio_cxl_create_memdev(struct vfio_pci_cxl_state *cxl, resource_size_t capacity) { @@ -279,6 +392,7 @@ void vfio_pci_cxl_detect_and_init(struct vfio_pci_core_device *vdev) goto regs_failed; } + cxl->precommitted = true; cxl->dpa_size = capacity; pci_dbg(pdev, "Device capacity: %llu MB\n", capacity >> 20); @@ -289,6 +403,10 @@ void vfio_pci_cxl_detect_and_init(struct vfio_pci_core_device *vdev) goto regs_failed; } + ret = vfio_cxl_create_region_helper(vdev, cxl, capacity); + if (ret) + goto regs_failed; + /* * Register probing succeeded. Assign vdev->cxl now so that * all subsequent helpers can access state via vdev->cxl. @@ -314,6 +432,7 @@ void vfio_pci_cxl_cleanup(struct vfio_pci_core_device *vdev) return; vfio_cxl_clean_virt_regs(cxl); + vfio_cxl_destroy_cxl_region(cxl); } MODULE_IMPORT_NS("CXL"); diff --git a/drivers/vfio/pci/cxl/vfio_cxl_priv.h b/drivers/vfio/pci/cxl/vfio_cxl_priv.h index 6359ad260bde..72a0d7d7e183 100644 --- a/drivers/vfio/pci/cxl/vfio_cxl_priv.h +++ b/drivers/vfio/pci/cxl/vfio_cxl_priv.h @@ -17,6 +17,10 @@ struct vfio_pci_cxl_state { struct cxl_memdev *cxlmd; struct cxl_root_decoder *cxlrd; struct cxl_endpoint_decoder *cxled; + struct cxl_region *region; + resource_size_t region_hpa; + size_t region_size; + void *region_vaddr; resource_size_t hdm_reg_offset; size_t hdm_reg_size; resource_size_t comp_reg_offset; @@ -28,6 +32,7 @@ struct vfio_pci_cxl_state { u8 hdm_count; u8 comp_reg_bar; bool cache_capable; + bool precommitted; }; /* Register access sizes */ @@ -87,5 +92,8 @@ void vfio_cxl_reinit_comp_regs(struct vfio_pci_cxl_state *cxl); resource_size_t vfio_cxl_read_committed_decoder_size(struct vfio_pci_core_device *vdev, struct vfio_pci_cxl_state *cxl); +int vfio_cxl_create_cxl_region(struct vfio_pci_cxl_state *cxl, + resource_size_t size); +void vfio_cxl_destroy_cxl_region(struct vfio_pci_cxl_state *cxl); #endif /* __LINUX_VFIO_CXL_PRIV_H */ -- 2.25.1
