diff options
Diffstat (limited to 'drivers/misc/cxl/vphb.c')
-rw-r--r-- | drivers/misc/cxl/vphb.c | 51 |
1 files changed, 29 insertions, 22 deletions
diff --git a/drivers/misc/cxl/vphb.c b/drivers/misc/cxl/vphb.c index 3519acebfdab..639a343b7836 100644 --- a/drivers/misc/cxl/vphb.c +++ b/drivers/misc/cxl/vphb.c @@ -76,23 +76,22 @@ static int cxl_pcie_cfg_record(u8 bus, u8 devfn) return (bus << 8) + devfn; } -static int cxl_pcie_config_info(struct pci_bus *bus, unsigned int devfn, - struct cxl_afu **_afu, int *_record) +static inline struct cxl_afu *pci_bus_to_afu(struct pci_bus *bus) { - struct pci_controller *phb; - struct cxl_afu *afu; - int record; + struct pci_controller *phb = bus ? pci_bus_to_host(bus) : NULL; - phb = pci_bus_to_host(bus); - if (phb == NULL) - return PCIBIOS_DEVICE_NOT_FOUND; + return phb ? phb->private_data : NULL; +} + +static inline int cxl_pcie_config_info(struct pci_bus *bus, unsigned int devfn, + struct cxl_afu *afu, int *_record) +{ + int record; - afu = (struct cxl_afu *)phb->private_data; record = cxl_pcie_cfg_record(bus->number, devfn); if (record > afu->crs_num) return PCIBIOS_DEVICE_NOT_FOUND; - *_afu = afu; *_record = record; return 0; } @@ -106,9 +105,14 @@ static int cxl_pcie_read_config(struct pci_bus *bus, unsigned int devfn, u16 val16; u32 val32; - rc = cxl_pcie_config_info(bus, devfn, &afu, &record); + afu = pci_bus_to_afu(bus); + /* Grab a reader lock on afu. */ + if (afu == NULL || !down_read_trylock(&afu->configured_rwsem)) + return PCIBIOS_DEVICE_NOT_FOUND; + + rc = cxl_pcie_config_info(bus, devfn, afu, &record); if (rc) - return rc; + goto out; switch (len) { case 1: @@ -127,10 +131,9 @@ static int cxl_pcie_read_config(struct pci_bus *bus, unsigned int devfn, WARN_ON(1); } - if (rc) - return PCIBIOS_DEVICE_NOT_FOUND; - - return PCIBIOS_SUCCESSFUL; +out: + up_read(&afu->configured_rwsem); + return rc ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL; } static int cxl_pcie_write_config(struct pci_bus *bus, unsigned int devfn, @@ -139,9 +142,14 @@ static int cxl_pcie_write_config(struct pci_bus *bus, unsigned int devfn, int rc, record; struct cxl_afu *afu; - rc = cxl_pcie_config_info(bus, devfn, &afu, &record); + afu = pci_bus_to_afu(bus); + /* Grab a reader lock on afu. */ + if (afu == NULL || !down_read_trylock(&afu->configured_rwsem)) + return PCIBIOS_DEVICE_NOT_FOUND; + + rc = cxl_pcie_config_info(bus, devfn, afu, &record); if (rc) - return rc; + goto out; switch (len) { case 1: @@ -157,10 +165,9 @@ static int cxl_pcie_write_config(struct pci_bus *bus, unsigned int devfn, WARN_ON(1); } - if (rc) - return PCIBIOS_SET_FAILED; - - return PCIBIOS_SUCCESSFUL; +out: + up_read(&afu->configured_rwsem); + return rc ? PCIBIOS_SET_FAILED : PCIBIOS_SUCCESSFUL; } static struct pci_ops cxl_pcie_pci_ops = |