PCI/VPD: Remove struct pci_vpd.valid member

Instead of having a separate flag, use vp->len != 0 as indicator that VPD
validity has been checked.  Now vpd->len == PCI_VPD_SZ_INVALID indicates
that VPD is invalid.

Link: https://lore.kernel.org/r/9f777bc7-5316-e1b8-e5d4-f9f609bdb5dd@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c
index e243954..9d9cff5 100644 (file)
--- a/drivers/pci/vpd.c
+++ b/drivers/pci/vpd.c
@@ -17,7 +17,6 @@ struct pci_vpd {
        struct mutex    lock;
        unsigned int    len;
        u8              cap;
-       unsigned int    valid:1;
 };
 
 static struct pci_dev *pci_get_func0_dev(struct pci_dev *dev)
@@ -25,7 +24,8 @@ static struct pci_dev *pci_get_func0_dev(struct pci_dev *dev)
        return pci_get_slot(dev->bus, PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
 }
 
-#define PCI_VPD_MAX_SIZE (PCI_VPD_ADDR_MASK + 1)
+#define PCI_VPD_MAX_SIZE       (PCI_VPD_ADDR_MASK + 1)
+#define PCI_VPD_SZ_INVALID     UINT_MAX
 
 /**
  * pci_vpd_size - determine actual size of Vital Product Data
@@ -36,6 +36,9 @@ static size_t pci_vpd_size(struct pci_dev *dev)
        size_t off = 0, size;
        unsigned char tag, header[1+2]; /* 1 byte tag, 2 bytes length */
 
+       /* Otherwise the following reads would fail. */
+       dev->vpd->len = PCI_VPD_MAX_SIZE;
+
        while (pci_read_vpd(dev, off, 1, header) == 1) {
                size = 0;
 
@@ -47,7 +50,7 @@ static size_t pci_vpd_size(struct pci_dev *dev)
                        if (pci_read_vpd(dev, off + 1, 2, &header[1]) != 2) {
                                pci_warn(dev, "failed VPD read at offset %zu\n",
                                         off + 1);
-                               return off;
+                               return off ?: PCI_VPD_SZ_INVALID;
                        }
                        size = pci_vpd_lrdt_size(header);
                        if (off + size > PCI_VPD_MAX_SIZE)
@@ -72,7 +75,7 @@ error:
        pci_info(dev, "invalid VPD tag %#04x (size %zu) at offset %zu%s\n",
                 header[0], size, off, off == 0 ?
                 "; assume missing optional EEPROM" : "");
-       return off;
+       return off ?: PCI_VPD_SZ_INVALID;
 }
 
 /*
@@ -127,12 +130,10 @@ static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count,
        if (pos < 0)
                return -EINVAL;
 
-       if (!vpd->valid) {
-               vpd->valid = 1;
+       if (!vpd->len)
                vpd->len = pci_vpd_size(dev);
-       }
 
-       if (vpd->len == 0)
+       if (vpd->len == PCI_VPD_SZ_INVALID)
                return -EIO;
 
        if (pos > vpd->len)
@@ -196,12 +197,10 @@ 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 (!vpd->valid) {
-               vpd->valid = 1;
+       if (!vpd->len)
                vpd->len = pci_vpd_size(dev);
-       }
 
-       if (vpd->len == 0)
+       if (vpd->len == PCI_VPD_SZ_INVALID)
                return -EIO;
 
        if (end > vpd->len)
@@ -250,10 +249,8 @@ void pci_vpd_init(struct pci_dev *dev)
        if (!vpd)
                return;
 
-       vpd->len = PCI_VPD_MAX_SIZE;
        mutex_init(&vpd->lock);
        vpd->cap = cap;
-       vpd->valid = 0;
        dev->vpd = vpd;
 }
 
@@ -422,8 +419,7 @@ DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
 static void quirk_blacklist_vpd(struct pci_dev *dev)
 {
        if (dev->vpd) {
-               dev->vpd->len = 0;
-               dev->vpd->valid = 1;
+               dev->vpd->len = PCI_VPD_SZ_INVALID;
                pci_warn(dev, FW_BUG "disabling VPD access (can't determine size of non-standard VPD format)\n");
        }
 }
@@ -454,7 +450,6 @@ static void pci_vpd_set_size(struct pci_dev *dev, size_t len)
        if (!vpd || len == 0 || len > PCI_VPD_MAX_SIZE)
                return;
 
-       vpd->valid = 1;
        vpd->len = len;
 }