From: Heiner Kallweit Date: Fri, 10 Sep 2021 06:22:06 +0000 (+0200) Subject: PCI/VPD: Add pci_read/write_vpd_any() X-Git-Tag: v6.6.17~8838^2~16^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=bf2928c7a284e31f9f91a004b5dca09c522157c0;p=platform%2Fkernel%2Flinux-rpi.git PCI/VPD: Add pci_read/write_vpd_any() In certain cases we need a variant of pci_read_vpd()/pci_write_vpd() that does not check against dev->vpd.len. Such cases are: - Reading VPD if dev->vpd.len isn't set yet (in pci_vpd_size()) - Devices that map non-VPD information to arbitrary places in VPD address space (example: Chelsio T3 EEPROM write-protect flag) Therefore add pci_read_vpd_any() and pci_write_vpd_any() that check against PCI_VPD_MAX_SIZE only. Link: https://lore.kernel.org/r/93ecce28-a158-f02a-d134-8afcaced8efe@gmail.com Signed-off-by: Heiner Kallweit Signed-off-by: Bjorn Helgaas Acked-by: Jakub Kicinski --- diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c index 4be2489..0a80471 100644 --- a/drivers/pci/vpd.c +++ b/drivers/pci/vpd.c @@ -156,9 +156,10 @@ static int pci_vpd_wait(struct pci_dev *dev, bool set) } static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count, - void *arg) + void *arg, bool check_size) { struct pci_vpd *vpd = &dev->vpd; + unsigned int max_len = check_size ? vpd->len : PCI_VPD_MAX_SIZE; int ret = 0; loff_t end = pos + count; u8 *buf = arg; @@ -169,11 +170,11 @@ static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count, if (pos < 0) return -EINVAL; - if (pos > vpd->len) + if (pos >= max_len) return 0; - if (end > vpd->len) { - end = vpd->len; + if (end > max_len) { + end = max_len; count = end - pos; } @@ -217,9 +218,10 @@ static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count, } static ssize_t pci_vpd_write(struct pci_dev *dev, loff_t pos, size_t count, - const void *arg) + const void *arg, bool check_size) { struct pci_vpd *vpd = &dev->vpd; + unsigned int max_len = check_size ? vpd->len : PCI_VPD_MAX_SIZE; const u8 *buf = arg; loff_t end = pos + count; int ret = 0; @@ -230,7 +232,7 @@ static ssize_t pci_vpd_write(struct pci_dev *dev, loff_t pos, size_t count, if (pos < 0 || (pos & 3) || (count & 3)) return -EINVAL; - if (end > vpd->len) + if (end > max_len) return -EINVAL; if (mutex_lock_killable(&vpd->lock)) @@ -381,6 +383,24 @@ static int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off, return -ENOENT; } +static ssize_t __pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf, + bool check_size) +{ + ssize_t ret; + + if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { + dev = pci_get_func0_dev(dev); + if (!dev) + return -ENODEV; + + ret = pci_vpd_read(dev, pos, count, buf, check_size); + pci_dev_put(dev); + return ret; + } + + return pci_vpd_read(dev, pos, count, buf, check_size); +} + /** * pci_read_vpd - Read one entry from Vital Product Data * @dev: PCI device struct @@ -390,6 +410,20 @@ static int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off, */ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf) { + return __pci_read_vpd(dev, pos, count, buf, true); +} +EXPORT_SYMBOL(pci_read_vpd); + +/* Same, but allow to access any address */ +ssize_t pci_read_vpd_any(struct pci_dev *dev, loff_t pos, size_t count, void *buf) +{ + return __pci_read_vpd(dev, pos, count, buf, false); +} +EXPORT_SYMBOL(pci_read_vpd_any); + +static ssize_t __pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, + const void *buf, bool check_size) +{ ssize_t ret; if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { @@ -397,14 +431,13 @@ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf) if (!dev) return -ENODEV; - ret = pci_vpd_read(dev, pos, count, buf); + ret = pci_vpd_write(dev, pos, count, buf, check_size); pci_dev_put(dev); return ret; } - return pci_vpd_read(dev, pos, count, buf); + return pci_vpd_write(dev, pos, count, buf, check_size); } -EXPORT_SYMBOL(pci_read_vpd); /** * pci_write_vpd - Write entry to Vital Product Data @@ -415,22 +448,17 @@ EXPORT_SYMBOL(pci_read_vpd); */ ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf) { - ssize_t ret; - - if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { - dev = pci_get_func0_dev(dev); - if (!dev) - return -ENODEV; - - ret = pci_vpd_write(dev, pos, count, buf); - pci_dev_put(dev); - return ret; - } - - return pci_vpd_write(dev, pos, count, buf); + return __pci_write_vpd(dev, pos, count, buf, true); } EXPORT_SYMBOL(pci_write_vpd); +/* Same, but allow to access any address */ +ssize_t pci_write_vpd_any(struct pci_dev *dev, loff_t pos, size_t count, const void *buf) +{ + return __pci_write_vpd(dev, pos, count, buf, false); +} +EXPORT_SYMBOL(pci_write_vpd_any); + int pci_vpd_find_ro_info_keyword(const void *buf, unsigned int len, const char *kw, unsigned int *size) { diff --git a/include/linux/pci.h b/include/linux/pci.h index cd8aa6f..9649bd9e 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1350,6 +1350,8 @@ void pci_unlock_rescan_remove(void); /* Vital Product Data routines */ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf); ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf); +ssize_t pci_read_vpd_any(struct pci_dev *dev, loff_t pos, size_t count, void *buf); +ssize_t pci_write_vpd_any(struct pci_dev *dev, loff_t pos, size_t count, const void *buf); /* Helper functions for low-level code (drivers/pci/setup-[bus,res].c) */ resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx);