This is a note to let you know that I've just added the patch titled
PCI: Export pci_intx_unmanaged() and pcim_intx()
to the 6.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-export-pci_intx_unmanaged-and-pcim_intx.patch
and it can be found in the queue-6.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d844e73c59c4f43a744897c4d7ee97d57ef6f27e
Author: Philipp Stanner <pstanner@xxxxxxxxxx>
Date: Mon Dec 9 14:06:23 2024 +0100
PCI: Export pci_intx_unmanaged() and pcim_intx()
[ Upstream commit f546e8033d8f3e45d49622f04ca2fde650b80f6d ]
pci_intx() is a hybrid function which sometimes performs devres operations,
depending on whether pcim_enable_device() has been used to enable the
pci_dev. This sometimes-managed nature of the function is problematic.
Notably, it causes the function to allocate under some circumstances which
makes it unusable from interrupt context.
Export pcim_intx() (which is always managed) and rename __pcim_intx()
(which is never managed) to pci_intx_unmanaged() and export it as well.
Then all callers of pci_intx() can be ported to the version they need,
depending whether they use pci_enable_device() or pcim_enable_device().
Link: https://lore.kernel.org/r/20241209130632.132074-3-pstanner@xxxxxxxxxx
Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Stable-dep-of: d555ed45a5a1 ("PCI: Restore original INTX_DISABLE bit by pcim_intx()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
index 3b59a86a764b1..3594eea379931 100644
--- a/drivers/pci/devres.c
+++ b/drivers/pci/devres.c
@@ -411,31 +411,12 @@ static inline bool mask_contains_bar(int mask, int bar)
return mask & BIT(bar);
}
-/*
- * This is a copy of pci_intx() used to bypass the problem of recursive
- * function calls due to the hybrid nature of pci_intx().
- */
-static void __pcim_intx(struct pci_dev *pdev, int enable)
-{
- u16 pci_command, new;
-
- pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
-
- if (enable)
- new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
- else
- new = pci_command | PCI_COMMAND_INTX_DISABLE;
-
- if (new != pci_command)
- pci_write_config_word(pdev, PCI_COMMAND, new);
-}
-
static void pcim_intx_restore(struct device *dev, void *data)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct pcim_intx_devres *res = data;
- __pcim_intx(pdev, res->orig_intx);
+ pci_intx_unmanaged(pdev, res->orig_intx);
}
static struct pcim_intx_devres *get_or_create_intx_devres(struct device *dev)
@@ -472,10 +453,11 @@ int pcim_intx(struct pci_dev *pdev, int enable)
return -ENOMEM;
res->orig_intx = !enable;
- __pcim_intx(pdev, enable);
+ pci_intx_unmanaged(pdev, enable);
return 0;
}
+EXPORT_SYMBOL_GPL(pcim_intx);
static void pcim_disable_device(void *pdev_raw)
{
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 661f98c6c63a3..d3c3425f7bc57 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4482,6 +4482,35 @@ void pci_disable_parity(struct pci_dev *dev)
}
}
+/**
+ * pci_intx_unmanaged - enables/disables PCI INTx for device dev,
+ * unmanaged version
+ * @pdev: the PCI device to operate on
+ * @enable: boolean: whether to enable or disable PCI INTx
+ *
+ * Enables/disables PCI INTx for device @pdev
+ *
+ * This function behavios identically to pci_intx(), but is never managed with
+ * devres.
+ */
+void pci_intx_unmanaged(struct pci_dev *pdev, int enable)
+{
+ u16 pci_command, new;
+
+ pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
+
+ if (enable)
+ new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
+ else
+ new = pci_command | PCI_COMMAND_INTX_DISABLE;
+
+ if (new == pci_command)
+ return;
+
+ pci_write_config_word(pdev, PCI_COMMAND, new);
+}
+EXPORT_SYMBOL_GPL(pci_intx_unmanaged);
+
/**
* pci_intx - enables/disables PCI INTx for device dev
* @pdev: the PCI device to operate on
diff --git a/include/linux/pci.h b/include/linux/pci.h
index db9b47ce3eefd..b5eb8bda655dc 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1350,6 +1350,7 @@ int __must_check pcim_set_mwi(struct pci_dev *dev);
int pci_try_set_mwi(struct pci_dev *dev);
void pci_clear_mwi(struct pci_dev *dev);
void pci_disable_parity(struct pci_dev *dev);
+void pci_intx_unmanaged(struct pci_dev *pdev, int enable);
void pci_intx(struct pci_dev *dev, int enable);
bool pci_check_and_mask_intx(struct pci_dev *dev);
bool pci_check_and_unmask_intx(struct pci_dev *dev);
@@ -2297,6 +2298,7 @@ static inline void pci_fixup_device(enum pci_fixup_pass pass,
struct pci_dev *dev) { }
#endif
+int pcim_intx(struct pci_dev *pdev, int enabled);
int pcim_request_all_regions(struct pci_dev *pdev, const char *name);
void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
