[PATCH 5.10.y 2/3] PCI/sysfs: Use sysfs_emit() and sysfs_emit_at() in "show" functions

From: Krzysztof Wilczyński kw@linux.com

[ Upstream commit ad025f8e46f3dbf09b1bf8d7a5b4ce858df74544 ]

The sysfs_emit() and sysfs_emit_at() functions were introduced to make it less ambiguous which function is preferred when writing to the output buffer in a device attribute's "show" callback [1].

Convert the PCI sysfs object "show" functions from sprintf(), snprintf() and scnprintf() to sysfs_emit() and sysfs_emit_at() accordingly, as the latter is aware of the PAGE_SIZE buffer and correctly returns the number of bytes written into the buffer.

No functional change intended.

[1] Documentation/filesystems/sysfs.rst

[bhelgaas: drop dsm_label_utf16s_to_utf8s(), link speed/width changes] Link: https://lore.kernel.org/r/20210416205856.3234481-10-kw@linux.com Signed-off-by: Krzysztof Wilczyński kw@linux.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Stable-dep-of: 48991e493507 ("PCI/sysfs: Ensure devices are powered for config reads") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/pci-label.c | 10 +++--- drivers/pci/pci-sysfs.c | 72 ++++++++++++++++++++--------------------- 2 files changed, 40 insertions(+), 42 deletions(-)

diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c index cd84cf52a92e1..6c406453b49f4 100644 --- a/drivers/pci/pci-label.c +++ b/drivers/pci/pci-label.c @@ -62,13 +62,11 @@ static size_t find_smbios_instance_string(struct pci_dev *pdev, char *buf, donboard->devfn == devfn) { if (buf) { if (attribute == SMBIOS_ATTR_INSTANCE_SHOW) - return scnprintf(buf, PAGE_SIZE, - "%d\n", - donboard->instance); + return sysfs_emit(buf, "%d\n", + donboard->instance); else if (attribute == SMBIOS_ATTR_LABEL_SHOW) - return scnprintf(buf, PAGE_SIZE, - "%s\n", - dmi->name); + return sysfs_emit(buf, "%s\n", + dmi->name); } return strlen(dmi->name); } diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 5a9d942198586..3fddd421bbe66 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -39,7 +39,7 @@ field##_show(struct device *dev, struct device_attribute *attr, char *buf) \ struct pci_dev *pdev; \ \ pdev = to_pci_dev(dev); \ - return sprintf(buf, format_string, pdev->field); \ + return sysfs_emit(buf, format_string, pdev->field); \ } \ static DEVICE_ATTR_RO(field)

@@ -56,7 +56,7 @@ static ssize_t broken_parity_status_show(struct device *dev, char *buf) { struct pci_dev *pdev = to_pci_dev(dev); - return sprintf(buf, "%u\n", pdev->broken_parity_status); + return sysfs_emit(buf, "%u\n", pdev->broken_parity_status); }

static ssize_t broken_parity_status_store(struct device *dev, @@ -129,7 +129,7 @@ static ssize_t power_state_show(struct device *dev, { struct pci_dev *pdev = to_pci_dev(dev);

- return sprintf(buf, "%s\n", pci_power_name(pdev->current_state)); + return sysfs_emit(buf, "%s\n", pci_power_name(pdev->current_state)); } static DEVICE_ATTR_RO(power_state);

@@ -138,10 +138,10 @@ static ssize_t resource_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pci_dev *pci_dev = to_pci_dev(dev); - char *str = buf; int i; int max; resource_size_t start, end; + size_t len = 0;

if (pci_dev->subordinate) max = DEVICE_COUNT_RESOURCE; @@ -151,12 +151,12 @@ static ssize_t resource_show(struct device *dev, struct device_attribute *attr, for (i = 0; i < max; i++) { struct resource *res = &pci_dev->resource[i]; pci_resource_to_user(pci_dev, i, res, &start, &end); - str += sprintf(str, "0x%016llx 0x%016llx 0x%016llx\n", - (unsigned long long)start, - (unsigned long long)end, - (unsigned long long)res->flags); + len += sysfs_emit_at(buf, len, "0x%016llx 0x%016llx 0x%016llx\n", + (unsigned long long)start, + (unsigned long long)end, + (unsigned long long)res->flags); } - return (str - buf); + return len; } static DEVICE_ATTR_RO(resource);

@@ -165,8 +165,8 @@ static ssize_t max_link_speed_show(struct device *dev, { struct pci_dev *pdev = to_pci_dev(dev);

- return sprintf(buf, "%s\n", - pci_speed_string(pcie_get_speed_cap(pdev))); + return sysfs_emit(buf, "%s\n", + pci_speed_string(pcie_get_speed_cap(pdev))); } static DEVICE_ATTR_RO(max_link_speed);

@@ -175,7 +175,7 @@ static ssize_t max_link_width_show(struct device *dev, { struct pci_dev *pdev = to_pci_dev(dev);

- return sprintf(buf, "%u\n", pcie_get_width_cap(pdev)); + return sysfs_emit(buf, "%u\n", pcie_get_width_cap(pdev)); } static DEVICE_ATTR_RO(max_link_width);

@@ -193,7 +193,7 @@ static ssize_t current_link_speed_show(struct device *dev,

speed = pcie_link_speed[linkstat & PCI_EXP_LNKSTA_CLS];

- return sprintf(buf, "%s\n", pci_speed_string(speed)); + return sysfs_emit(buf, "%s\n", pci_speed_string(speed)); } static DEVICE_ATTR_RO(current_link_speed);

@@ -208,7 +208,7 @@ static ssize_t current_link_width_show(struct device *dev, if (err) return -EINVAL;

- return sprintf(buf, "%u\n", + return sysfs_emit(buf, "%u\n", (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT); } static DEVICE_ATTR_RO(current_link_width); @@ -225,7 +225,7 @@ static ssize_t secondary_bus_number_show(struct device *dev, if (err) return -EINVAL;

- return sprintf(buf, "%u\n", sec_bus); + return sysfs_emit(buf, "%u\n", sec_bus); } static DEVICE_ATTR_RO(secondary_bus_number);

@@ -241,7 +241,7 @@ static ssize_t subordinate_bus_number_show(struct device *dev, if (err) return -EINVAL;

- return sprintf(buf, "%u\n", sub_bus); + return sysfs_emit(buf, "%u\n", sub_bus); } static DEVICE_ATTR_RO(subordinate_bus_number);

@@ -251,7 +251,7 @@ static ssize_t ari_enabled_show(struct device *dev, { struct pci_dev *pci_dev = to_pci_dev(dev);

- return sprintf(buf, "%u\n", pci_ari_enabled(pci_dev->bus)); + return sysfs_emit(buf, "%u\n", pci_ari_enabled(pci_dev->bus)); } static DEVICE_ATTR_RO(ari_enabled);

@@ -260,11 +260,11 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, { struct pci_dev *pci_dev = to_pci_dev(dev);

- return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X\n", - pci_dev->vendor, pci_dev->device, - pci_dev->subsystem_vendor, pci_dev->subsystem_device, - (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8), - (u8)(pci_dev->class)); + return sysfs_emit(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X\n", + pci_dev->vendor, pci_dev->device, + pci_dev->subsystem_vendor, pci_dev->subsystem_device, + (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8), + (u8)(pci_dev->class)); } static DEVICE_ATTR_RO(modalias);

@@ -302,7 +302,7 @@ static ssize_t enable_show(struct device *dev, struct device_attribute *attr, struct pci_dev *pdev;

pdev = to_pci_dev(dev); - return sprintf(buf, "%u\n", atomic_read(&pdev->enable_cnt)); + return sysfs_emit(buf, "%u\n", atomic_read(&pdev->enable_cnt)); } static DEVICE_ATTR_RW(enable);

@@ -338,7 +338,7 @@ static ssize_t numa_node_store(struct device *dev, static ssize_t numa_node_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", dev->numa_node); + return sysfs_emit(buf, "%d\n", dev->numa_node); } static DEVICE_ATTR_RW(numa_node); #endif @@ -348,7 +348,7 @@ static ssize_t dma_mask_bits_show(struct device *dev, { struct pci_dev *pdev = to_pci_dev(dev);

- return sprintf(buf, "%d\n", fls64(pdev->dma_mask)); + return sysfs_emit(buf, "%d\n", fls64(pdev->dma_mask)); } static DEVICE_ATTR_RO(dma_mask_bits);

@@ -356,7 +356,7 @@ static ssize_t consistent_dma_mask_bits_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", fls64(dev->coherent_dma_mask)); + return sysfs_emit(buf, "%d\n", fls64(dev->coherent_dma_mask)); } static DEVICE_ATTR_RO(consistent_dma_mask_bits);

@@ -366,9 +366,9 @@ static ssize_t msi_bus_show(struct device *dev, struct device_attribute *attr, struct pci_dev *pdev = to_pci_dev(dev); struct pci_bus *subordinate = pdev->subordinate;

- return sprintf(buf, "%u\n", subordinate ? - !(subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI) - : !pdev->no_msi); + return sysfs_emit(buf, "%u\n", subordinate ? + !(subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI) + : !pdev->no_msi); }

static ssize_t msi_bus_store(struct device *dev, struct device_attribute *attr, @@ -545,7 +545,7 @@ static ssize_t d3cold_allowed_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pci_dev *pdev = to_pci_dev(dev); - return sprintf(buf, "%u\n", pdev->d3cold_allowed); + return sysfs_emit(buf, "%u\n", pdev->d3cold_allowed); } static DEVICE_ATTR_RW(d3cold_allowed); #endif @@ -559,7 +559,7 @@ static ssize_t devspec_show(struct device *dev,

if (np == NULL) return 0; - return sprintf(buf, "%pOF", np); + return sysfs_emit(buf, "%pOF", np); } static DEVICE_ATTR_RO(devspec); #endif @@ -605,7 +605,7 @@ static ssize_t driver_override_show(struct device *dev, ssize_t len;

device_lock(dev); - len = scnprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override); + len = sysfs_emit(buf, "%s\n", pdev->driver_override); device_unlock(dev); return len; } @@ -681,11 +681,11 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr, struct pci_dev *vga_dev = vga_default_device();

if (vga_dev) - return sprintf(buf, "%u\n", (pdev == vga_dev)); + return sysfs_emit(buf, "%u\n", (pdev == vga_dev));

- return sprintf(buf, "%u\n", - !!(pdev->resource[PCI_ROM_RESOURCE].flags & - IORESOURCE_ROM_SHADOW)); + return sysfs_emit(buf, "%u\n", + !!(pdev->resource[PCI_ROM_RESOURCE].flags & + IORESOURCE_ROM_SHADOW)); } static DEVICE_ATTR_RO(boot_vga);