-@@ -783,7 +783,7 @@ void device_del(struct device * dev)

-@@ -605,13 +594,21 @@ int device_add(struct device *dev)

-@@ -777,12 +774,18 @@ void device_del(struct device * dev)

- kfree(dev->devt_attr);

- }

-@@ -913,9 +916,20 @@ struct device * device_find_child(struct

-@@ -366,8 +366,6 @@ struct pci_driver {

-From owner-linux-pci@atrey.karlin.mff.cuni.cz Thu Mar 8 12:05:21 2007

-From: Eric W. Biederman <ebiederm@xmission.com>

-Date: Thu, 08 Mar 2007 13:04:57 -0700

-Subject: msi: Safer state caching.

-To: Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>

-Cc: Jeff Garzik <jeff@garzik.org>, "Kok, Auke" <auke-jan.h.kok@intel.com>, Ingo Molnar <mingo@elte.hu>, "Michael S. Tsirkin" <mst@mellanox.co.il>, Pavel Machek <pavel@ucw.cz>, Jens Axboe <jens.axboe@oracle.com>, Adrian Bunk <bunk@stusta.de>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>, linux-pm@lists.osdl.org, Michal Piotrowski <michal.k.k.piotrowski@gmail.com>, Greg Kroah-Hartman <gregkh@suse.de>, <linux-pci@atrey.karlin.mff.cuni.cz>, michael@ellerman.id.au

-Message-ID: <m1ps7j5wnq.fsf_-_@ebiederm.dsl.xmission.com>

-

-From: Eric W. Biederman <ebiederm@xmission.com>

-

-

-There are two ways pci_save_state and pci_restore_state are used. As

-helper functions during suspend/resume, and as helper functions around

-a hardware reset event. When used as helper functions around a hardware

-reset event there is no reason to believe the calls will be paired, nor

-is there a good reason to believe that if we restore the msi state from

-before the reset that it will match the current msi state. Since arch

-code may change the msi message without going through the driver, drivers

-currently do not have enough information to even know when to call

-pci_save_state to ensure they will have msi state in sync with the other

-kernel irq reception data structures.

-

-It turns out the solution is straight forward, cache the state in the

-existing msi data structures (not the magic pci saved things) and

-have the msi code update the cached state each time we write to the hardware.

-This means we never need to read the hardware to figure out what the hardware

-state should be.

-

-By modifying the caching in this manner we get to remove our save_state

-routines and only need to provide restore_state routines.

-

-The only fields that were at all tricky to regenerate were the msi and msi-x

-control registers and the way we regenerate them currently is a bit dependent

-upon assumptions on how we use the allow msi registers to be configured and used

-making the code a little bit brittle. If we ever change what cases we allow

-or how we configure the msi bits we can address the fragility then.

-

-Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

-Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

-

----

- drivers/pci/msi.c | 150 +++++++----------------------------------------

- drivers/pci/pci.c | 2

- drivers/pci/pci.h | 2

- include/linux/msi.h | 8 --

- include/linux/pci_regs.h | 1

- 5 files changed, 29 insertions(+), 134 deletions(-)

-

---- a/drivers/pci/msi.c

-+++ b/drivers/pci/msi.c

-@@ -100,6 +100,7 @@ static void msi_set_mask_bit(unsigned in

- BUG();

- break;

- }

-+ entry->msi_attrib.masked = !!flag;

- }

-

- void read_msi_msg(unsigned int irq, struct msi_msg *msg)

-@@ -179,6 +180,7 @@ void write_msi_msg(unsigned int irq, str

- default:

- BUG();

- }

-+ entry->msg = *msg;

- }

-

- void mask_msi_irq(unsigned int irq)

-@@ -225,164 +227,60 @@ static struct msi_desc* alloc_msi_entry(

- }

-

- #ifdef CONFIG_PM

--static int __pci_save_msi_state(struct pci_dev *dev)

--{

-- int pos, i = 0;

-- u16 control;

-- struct pci_cap_saved_state *save_state;

-- u32 *cap;

--

-- if (!dev->msi_enabled)

-- return 0;

--

-- pos = pci_find_capability(dev, PCI_CAP_ID_MSI);

-- if (pos <= 0)

-- return 0;

--

-- save_state = kzalloc(sizeof(struct pci_cap_saved_state) + sizeof(u32) * 5,

-- GFP_KERNEL);

-- if (!save_state) {

-- printk(KERN_ERR "Out of memory in pci_save_msi_state\n");

-- return -ENOMEM;

-- }

-- cap = &save_state->data[0];

--

-- pci_read_config_dword(dev, pos, &cap[i++]);

-- control = cap[0] >> 16;

-- pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, &cap[i++]);

-- if (control & PCI_MSI_FLAGS_64BIT) {

-- pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, &cap[i++]);

-- pci_read_config_dword(dev, pos + PCI_MSI_DATA_64, &cap[i++]);

-- } else

-- pci_read_config_dword(dev, pos + PCI_MSI_DATA_32, &cap[i++]);

-- if (control & PCI_MSI_FLAGS_MASKBIT)

-- pci_read_config_dword(dev, pos + PCI_MSI_MASK_BIT, &cap[i++]);

-- save_state->cap_nr = PCI_CAP_ID_MSI;

-- pci_add_saved_cap(dev, save_state);

-- return 0;

--}

--

- static void __pci_restore_msi_state(struct pci_dev *dev)

- {

-- int i = 0, pos;

-+ int pos;

- u16 control;

-- struct pci_cap_saved_state *save_state;

-- u32 *cap;

-+ struct msi_desc *entry;

-

- if (!dev->msi_enabled)

- return;

-

-- save_state = pci_find_saved_cap(dev, PCI_CAP_ID_MSI);

-- pos = pci_find_capability(dev, PCI_CAP_ID_MSI);

-- if (!save_state || pos <= 0)

-- return;

-- cap = &save_state->data[0];

-+ entry = get_irq_msi(dev->irq);

-+ pos = entry->msi_attrib.pos;

-

- pci_intx(dev, 0); /* disable intx */

-- control = cap[i++] >> 16;

- msi_set_enable(dev, 0);

-- pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, cap[i++]);

-- if (control & PCI_MSI_FLAGS_64BIT) {

-- pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, cap[i++]);

-- pci_write_config_dword(dev, pos + PCI_MSI_DATA_64, cap[i++]);

-- } else

-- pci_write_config_dword(dev, pos + PCI_MSI_DATA_32, cap[i++]);

-- if (control & PCI_MSI_FLAGS_MASKBIT)

-- pci_write_config_dword(dev, pos + PCI_MSI_MASK_BIT, cap[i++]);

-+ write_msi_msg(dev->irq, &entry->msg);

-+ if (entry->msi_attrib.maskbit)

-+ msi_set_mask_bit(dev->irq, entry->msi_attrib.masked);

-+

-+ pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);

-+ control &= ~(PCI_MSI_FLAGS_QSIZE | PCI_MSI_FLAGS_ENABLE);

-+ if (entry->msi_attrib.maskbit || !entry->msi_attrib.masked)

-+ control |= PCI_MSI_FLAGS_ENABLE;

- pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);

-- pci_remove_saved_cap(save_state);

-- kfree(save_state);

--}

--

--static int __pci_save_msix_state(struct pci_dev *dev)

--{

-- int pos;

-- int irq, head, tail = 0;

-- u16 control;

-- struct pci_cap_saved_state *save_state;

--

-- if (!dev->msix_enabled)

-- return 0;

--

-- pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

-- if (pos <= 0)

-- return 0;

--

-- /* save the capability */

-- pci_read_config_word(dev, msi_control_reg(pos), &control);

-- save_state = kzalloc(sizeof(struct pci_cap_saved_state) + sizeof(u16),

-- GFP_KERNEL);

-- if (!save_state) {

-- printk(KERN_ERR "Out of memory in pci_save_msix_state\n");

-- return -ENOMEM;

-- }

-- *((u16 *)&save_state->data[0]) = control;

--

-- /* save the table */

-- irq = head = dev->first_msi_irq;

-- while (head != tail) {

-- struct msi_desc *entry;

--

-- entry = get_irq_msi(irq);

-- read_msi_msg(irq, &entry->msg_save);

--

-- tail = entry->link.tail;

-- irq = tail;

-- }

--

-- save_state->cap_nr = PCI_CAP_ID_MSIX;

-- pci_add_saved_cap(dev, save_state);

-- return 0;

--}

--

--int pci_save_msi_state(struct pci_dev *dev)

--{

-- int rc;

--

-- rc = __pci_save_msi_state(dev);

-- if (rc)

-- return rc;

--

-- rc = __pci_save_msix_state(dev);

--

-- return rc;

- }

-

- static void __pci_restore_msix_state(struct pci_dev *dev)

- {

-- u16 save;

- int pos;

- int irq, head, tail = 0;

- struct msi_desc *entry;

-- struct pci_cap_saved_state *save_state;

-+ u16 control;

-

- if (!dev->msix_enabled)

- return;

-

-- save_state = pci_find_saved_cap(dev, PCI_CAP_ID_MSIX);

-- if (!save_state)

-- return;

-- save = *((u16 *)&save_state->data[0]);

-- pci_remove_saved_cap(save_state);

-- kfree(save_state);

--

-- pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);

-- if (pos <= 0)

-- return;

--

- /* route the table */

- pci_intx(dev, 0); /* disable intx */

- msix_set_enable(dev, 0);

- irq = head = dev->first_msi_irq;

-+ entry = get_irq_msi(irq);

-+ pos = entry->msi_attrib.pos;

- while (head != tail) {

- entry = get_irq_msi(irq);

-- write_msi_msg(irq, &entry->msg_save);

-+ write_msi_msg(irq, &entry->msg);

-+ msi_set_mask_bit(irq, entry->msi_attrib.masked);

-

- tail = entry->link.tail;

- irq = tail;

- }

-

-- pci_write_config_word(dev, msi_control_reg(pos), save);

-+ pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);

-+ control &= ~PCI_MSIX_FLAGS_MASKALL;

-+ control |= PCI_MSIX_FLAGS_ENABLE;

-+ pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);

- }

-

- void pci_restore_msi_state(struct pci_dev *dev)

-@@ -420,6 +318,7 @@ static int msi_capability_init(struct pc

- entry->msi_attrib.is_64 = is_64bit_address(control);

- entry->msi_attrib.entry_nr = 0;

- entry->msi_attrib.maskbit = is_mask_bit_support(control);

-+ entry->msi_attrib.masked = 1;

- entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */

- entry->msi_attrib.pos = pos;

- if (is_mask_bit_support(control)) {

-@@ -507,6 +406,7 @@ static int msix_capability_init(struct p

- entry->msi_attrib.is_64 = 1;

- entry->msi_attrib.entry_nr = j;

- entry->msi_attrib.maskbit = 1;

-+ entry->msi_attrib.masked = 1;

- entry->msi_attrib.default_irq = dev->irq;

- entry->msi_attrib.pos = pos;

- entry->dev = dev;

---- a/drivers/pci/pci.c

-+++ b/drivers/pci/pci.c

-@@ -638,8 +638,6 @@ pci_save_state(struct pci_dev *dev)

- /* XXX: 100% dword access ok here? */

- for (i = 0; i < 16; i++)

- pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);

-- if ((i = pci_save_msi_state(dev)) != 0)

-- return i;

- if ((i = pci_save_pcie_state(dev)) != 0)

- return i;

- if ((i = pci_save_pcix_state(dev)) != 0)

---- a/drivers/pci/pci.h

-+++ b/drivers/pci/pci.h

-@@ -52,10 +52,8 @@ static inline void pci_no_msi(void) { }

- #endif

-

- #if defined(CONFIG_PCI_MSI) && defined(CONFIG_PM)

--int pci_save_msi_state(struct pci_dev *dev);

- void pci_restore_msi_state(struct pci_dev *dev);

- #else

--static inline int pci_save_msi_state(struct pci_dev *dev) { return 0; }

- static inline void pci_restore_msi_state(struct pci_dev *dev) {}

- #endif

-

---- a/include/linux/msi.h

-+++ b/include/linux/msi.h

-@@ -17,7 +17,7 @@ struct msi_desc {

- struct {

- __u8 type : 5; /* {0: unused, 5h:MSI, 11h:MSI-X} */

- __u8 maskbit : 1; /* mask-pending bit supported ? */

-- __u8 unused : 1;

-+ __u8 masked : 1;

- __u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */

- __u8 pos; /* Location of the msi capability */

- __u16 entry_nr; /* specific enabled entry */

-@@ -32,10 +32,8 @@ struct msi_desc {

- void __iomem *mask_base;

- struct pci_dev *dev;

-

--#ifdef CONFIG_PM

-- /* PM save area for MSIX address/data */

-- struct msi_msg msg_save;

--#endif

-+ /* Last set MSI message */

-+ struct msi_msg msg;

- };

-

- /*

---- a/include/linux/pci_regs.h

-+++ b/include/linux/pci_regs.h

-@@ -296,6 +296,7 @@

- #define PCI_MSIX_FLAGS 2

- #define PCI_MSIX_FLAGS_QSIZE 0x7FF

- #define PCI_MSIX_FLAGS_ENABLE (1 << 15)

-+#define PCI_MSIX_FLAGS_MASKALL (1 << 14)

- #define PCI_MSIX_FLAGS_BIRMASK (7 << 0)

- #define PCI_MSIX_FLAGS_BITMASK (1 << 0)

-

-@@ -893,6 +893,34 @@ pci_disable_device(struct pci_dev *dev)

-@@ -1405,4 +1433,5 @@ EXPORT_SYMBOL(pci_set_power_state);

-@@ -537,6 +550,7 @@ static inline int pci_is_managed(struct

-From owner-linux-pci@atrey.karlin.mff.cuni.cz Thu Mar 8 12:06:39 2007

-From: Eric W. Biederman <ebiederm@xmission.com>

-Date: Thu, 08 Mar 2007 13:06:13 -0700

-Subject: pci: Repair pci_save/restore_state so we can restore one save many times.

-To: Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>

-Cc: Jeff Garzik <jeff@garzik.org>, "Kok, Auke" <auke-jan.h.kok@intel.com>, Ingo Molnar <mingo@elte.hu>, "Michael S. Tsirkin" <mst@mellanox.co.il>, Pavel Machek <pavel@ucw.cz>, Jens Axboe <jens.axboe@oracle.com>, Adrian Bunk <bunk@stusta.de>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>, linux-pm@lists.osdl.org, Michal Piotrowski <michal.k.k.piotrowski@gmail.com>, Greg Kroah-Hartman <gregkh@suse.de>, <linux-pci@atrey.karlin.mff.cuni.cz>, michael@ellerman.id.au

-Message-ID: <m1lki75wlm.fsf_-_@ebiederm.dsl.xmission.com>

-

-

-From: Eric W. Biederman <ebiederm@xmission.com>

-

-Because we do not reserve space for the pci-x and pci-e state in struct

-pci dev we need to dynamically allocate it. However because we need

-to support restore being called multiple times after a single save

-it is never safe to free the buffers we have allocated to hold the

-state.

-

-So this patch modifies the save routines to first check to see

-if we have already allocated a state buffer before allocating

-a new one. Then the restore routines are modified to not free

-the state after restoring it. Simple and it fixes some subtle

-error path handling bugs, that are hard to test for.

-

-Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

-Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

-

----

- drivers/pci/pci.c | 12 ++++++------

- include/linux/pci.h | 5 -----

- 2 files changed, 6 insertions(+), 11 deletions(-)

-

---- a/drivers/pci/pci.c

-+++ b/drivers/pci/pci.c

-@@ -551,7 +551,9 @@ static int pci_save_pcie_state(struct pc

- if (pos <= 0)

- return 0;

-

-- save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);

-+ save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);

-+ if (!save_state)

-+ save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);

- if (!save_state) {

- dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");

- return -ENOMEM;

-@@ -582,8 +584,6 @@ static void pci_restore_pcie_state(struc

- pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);

- pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);

- pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);

-- pci_remove_saved_cap(save_state);

-- kfree(save_state);

- }

-

-

-@@ -597,7 +597,9 @@ static int pci_save_pcix_state(struct pc

- if (pos <= 0)

- return 0;

-

-- save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);

-+ save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);

-+ if (!save_state)

-+ save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);

- if (!save_state) {

- dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");

- return -ENOMEM;

-@@ -622,8 +624,6 @@ static void pci_restore_pcix_state(struc

- cap = (u16 *)&save_state->data[0];

-

- pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);

-- pci_remove_saved_cap(save_state);

-- kfree(save_state);

- }

-

-

---- a/include/linux/pci.h

-+++ b/include/linux/pci.h

-@@ -222,11 +222,6 @@ static inline void pci_add_saved_cap(str

- hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);

- }

-

--static inline void pci_remove_saved_cap(struct pci_cap_saved_state *cap)

--{

-- hlist_del(&cap->next);

--}

--

- /*

- * For PCI devices, the region numbers are assigned this way:

- *

-pci/msi-safer-state-caching.patch

-pci/pci-repair-pci_save-restore_state-so-we-can-restore-one-save-many-times.patch

-2.6.21-rc3-git7