Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754364AbbGBOL6 (ORCPT ); Thu, 2 Jul 2015 10:11:58 -0400 Received: from mail-la0-f46.google.com ([209.85.215.46]:33293 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753055AbbGBOLb (ORCPT ); Thu, 2 Jul 2015 10:11:31 -0400 From: Dmitry Kalinkin To: linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org Cc: Martyn Welch , Manohar Vanga , Greg Kroah-Hartman , Igor Alekseev , Dmitry Kalinkin Subject: [PATCH 3/3] vme: change bus error handling scheme Date: Thu, 2 Jul 2015 17:11:06 +0300 Message-Id: <1435846266-26958-4-git-send-email-dmitry.kalinkin@gmail.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1435846266-26958-1-git-send-email-dmitry.kalinkin@gmail.com> References: <1435846266-26958-1-git-send-email-dmitry.kalinkin@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11631 Lines: 352 The current VME bus error handler adds errors to the bridge error list. vme_master_{read,write} then traverses that list to look for relevant errors. Such scheme didn't work well for accesses going through vme_master_mmap because they would also allocate a vme_bus_error, but have no way to do vme_clear_errors call to free that memory. This changes the error handling process to be other way around: now vme_master_{read,write} defines a window in VME address space that will catch possible errors. VME bus error interrupt only traverses these windows and marks those that had errors in them. Signed-off-by: Dmitry Kalinkin Cc: Igor Alekseev --- drivers/vme/bridges/vme_ca91cx42.c | 3 +- drivers/vme/bridges/vme_tsi148.c | 83 +++++++++++++++++----------------- drivers/vme/vme.c | 92 ++++++++++++++------------------------ drivers/vme/vme_bridge.h | 23 ++++++---- 4 files changed, 91 insertions(+), 110 deletions(-) diff --git a/drivers/vme/bridges/vme_ca91cx42.c b/drivers/vme/bridges/vme_ca91cx42.c index f692efc..834883d 100644 --- a/drivers/vme/bridges/vme_ca91cx42.c +++ b/drivers/vme/bridges/vme_ca91cx42.c @@ -204,8 +204,7 @@ static int ca91cx42_irq_init(struct vme_bridge *ca91cx42_bridge) /* Need pdev */ pdev = container_of(ca91cx42_bridge->parent, struct pci_dev, dev); - /* Initialise list for VME bus errors */ - INIT_LIST_HEAD(&ca91cx42_bridge->vme_errors); + INIT_LIST_HEAD(&ca91cx42_bridge->vme_error_handlers); mutex_init(&ca91cx42_bridge->irq_mtx); diff --git a/drivers/vme/bridges/vme_tsi148.c b/drivers/vme/bridges/vme_tsi148.c index 76ccfae..b0132e0 100644 --- a/drivers/vme/bridges/vme_tsi148.c +++ b/drivers/vme/bridges/vme_tsi148.c @@ -314,8 +314,7 @@ static int tsi148_irq_init(struct vme_bridge *tsi148_bridge) bridge = tsi148_bridge->driver_priv; - /* Initialise list for VME bus errors */ - INIT_LIST_HEAD(&tsi148_bridge->vme_errors); + INIT_LIST_HEAD(&tsi148_bridge->vme_error_handlers); mutex_init(&tsi148_bridge->irq_mtx); @@ -1187,7 +1186,7 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf, int retval, enabled; unsigned long long vme_base, size; u32 aspace, cycle, dwidth; - struct vme_bus_error *vme_err = NULL; + struct vme_error_handler *handler; struct vme_bridge *tsi148_bridge; void __iomem *addr = image->kern_base + offset; unsigned int done = 0; @@ -1197,6 +1196,17 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf, spin_lock(&image->lock); + if (err_chk) { + __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, + &cycle, &dwidth); + handler = vme_register_error_handler(tsi148_bridge, aspace, + vme_base + offset, count); + if (!handler) { + spin_unlock(&image->lock); + return -ENOMEM; + } + } + /* The following code handles VME address alignment. We cannot use * memcpy_xxx here because it may cut data transfers in to 8-bit * cycles when D16 or D32 cycles are required on the VME bus. @@ -1240,24 +1250,16 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf, out: retval = count; - if (!err_chk) - goto skip_chk; - - __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, &cycle, - &dwidth); - - vme_err = vme_find_error(tsi148_bridge, aspace, vme_base + offset, - count); - if (vme_err != NULL) { - dev_err(image->parent->parent, "First VME read error detected " - "an at address 0x%llx\n", vme_err->address); - retval = vme_err->address - (vme_base + offset); - /* Clear down save errors in this address range */ - vme_clear_errors(tsi148_bridge, aspace, vme_base + offset, - count); + if (err_chk) { + if (handler->num_errors) { + dev_err(image->parent->parent, + "First VME read error detected an at address 0x%llx\n", + handler->first_error); + retval = handler->first_error - (vme_base + offset); + } + vme_unregister_error_handler(handler); } -skip_chk: spin_unlock(&image->lock); return retval; @@ -1274,7 +1276,7 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf, unsigned int done = 0; unsigned int count32; - struct vme_bus_error *vme_err = NULL; + struct vme_error_handler *handler; struct vme_bridge *tsi148_bridge; struct tsi148_driver *bridge; @@ -1284,6 +1286,17 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf, spin_lock(&image->lock); + if (err_chk) { + __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, + &cycle, &dwidth); + handler = vme_register_error_handler(tsi148_bridge, aspace, + vme_base + offset, count); + if (!handler) { + spin_unlock(&image->lock); + return -ENOMEM; + } + } + /* Here we apply for the same strategy we do in master_read * function in order to assure the correct cycles. */ @@ -1333,30 +1346,18 @@ out: * We check for saved errors in the written address range/space. */ - if (!err_chk) - goto skip_chk; - - /* - * Get window info first, to maximise the time that the buffers may - * fluch on their own - */ - __tsi148_master_get(image, &enabled, &vme_base, &size, &aspace, &cycle, - &dwidth); - - ioread16(bridge->flush_image->kern_base + 0x7F000); + if (err_chk) { + ioread16(bridge->flush_image->kern_base + 0x7F000); - vme_err = vme_find_error(tsi148_bridge, aspace, vme_base + offset, - count); - if (vme_err != NULL) { - dev_warn(tsi148_bridge->parent, "First VME write error detected" - " an at address 0x%llx\n", vme_err->address); - retval = vme_err->address - (vme_base + offset); - /* Clear down save errors in this address range */ - vme_clear_errors(tsi148_bridge, aspace, vme_base + offset, - count); + if (handler->num_errors) { + dev_warn(tsi148_bridge->parent, + "First VME write error detected an at address 0x%llx\n", + handler->first_error); + retval = handler->first_error - (vme_base + offset); + } + vme_unregister_error_handler(handler); } -skip_chk: spin_unlock(&image->lock); return retval; diff --git a/drivers/vme/vme.c b/drivers/vme/vme.c index 2b79cd2..7a10d92 100644 --- a/drivers/vme/vme.c +++ b/drivers/vme/vme.c @@ -1026,76 +1026,52 @@ EXPORT_SYMBOL(vme_dma_free); void vme_bus_error_handler(struct vme_bridge *bridge, unsigned long long address, int am) { - struct vme_bus_error *error; - - error = kmalloc(sizeof(struct vme_bus_error), GFP_ATOMIC); - if (error) { - error->aspace = vme_get_aspace(am); - error->address = address; - list_add_tail(&error->list, &bridge->vme_errors); - } else { - dev_err(bridge->parent, - "Unable to alloc memory for VMEbus Error reporting\n"); + struct list_head *handler_pos = NULL; + struct vme_error_handler *handler; + u32 aspace = vme_get_aspace(am); + + list_for_each(handler_pos, &bridge->vme_error_handlers) { + handler = list_entry(handler_pos, struct vme_error_handler, + list); + if ((aspace == handler->aspace) && + (address >= handler->start) && + (address < handler->end)) { + if (!handler->num_errors) + handler->first_error = address; + if (handler->num_errors != UINT_MAX) + handler->num_errors++; + } } } EXPORT_SYMBOL(vme_bus_error_handler); -/* - * Find the first error in this address range - */ -struct vme_bus_error *vme_find_error(struct vme_bridge *bridge, u32 aspace, - unsigned long long address, size_t count) +struct vme_error_handler *vme_register_error_handler( + struct vme_bridge *bridge, u32 aspace, + unsigned long long address, size_t len) { - struct list_head *err_pos; - struct vme_bus_error *vme_err, *valid = NULL; - unsigned long long bound; - - bound = address + count; + struct vme_error_handler *handler; - err_pos = NULL; - /* Iterate through errors */ - list_for_each(err_pos, &bridge->vme_errors) { - vme_err = list_entry(err_pos, struct vme_bus_error, list); - if ((vme_err->aspace == aspace) && - (vme_err->address >= address) && - (vme_err->address < bound)) { + handler = kmalloc(sizeof(*handler), GFP_KERNEL); + if (!handler) + return NULL; - valid = vme_err; - break; - } - } + handler->aspace = aspace; + handler->start = address; + handler->end = address + len; + handler->num_errors = 0; + handler->first_error = 0; + list_add_tail(&handler->list, &bridge->vme_error_handlers); - return valid; + return handler; } -EXPORT_SYMBOL(vme_find_error); +EXPORT_SYMBOL(vme_register_error_handler); -/* - * Clear errors in the provided address range. - */ -void vme_clear_errors(struct vme_bridge *bridge, u32 aspace, - unsigned long long address, size_t count) +void vme_unregister_error_handler(struct vme_error_handler *handler) { - struct list_head *err_pos, *temp; - struct vme_bus_error *vme_err; - unsigned long long bound; - - bound = address + count; - - err_pos = NULL; - /* Iterate through errors */ - list_for_each_safe(err_pos, temp, &bridge->vme_errors) { - vme_err = list_entry(err_pos, struct vme_bus_error, list); - - if ((vme_err->aspace == aspace) && - (vme_err->address >= address) && - (vme_err->address < bound)) { - - list_del(err_pos); - kfree(vme_err); - } - } + list_del(&handler->list); + kfree(handler); } -EXPORT_SYMBOL(vme_clear_errors); +EXPORT_SYMBOL(vme_unregister_error_handler); void vme_irq_handler(struct vme_bridge *bridge, int level, int statid) { diff --git a/drivers/vme/vme_bridge.h b/drivers/vme/vme_bridge.h index 92fbe18..397578a 100644 --- a/drivers/vme/vme_bridge.h +++ b/drivers/vme/vme_bridge.h @@ -75,10 +75,13 @@ struct vme_lm_resource { int monitors; }; -struct vme_bus_error { +struct vme_error_handler { struct list_head list; - u32 aspace; - unsigned long long address; + unsigned long long start; /* Beginning of error window */ + unsigned long long end; /* End of error window */ + unsigned long long first_error; /* Address of the first error */ + u32 aspace; /* Address space of error window*/ + unsigned num_errors; /* Number of errors */ }; struct vme_callback { @@ -106,8 +109,10 @@ struct vme_bridge { struct list_head dma_resources; struct list_head lm_resources; - struct list_head vme_errors; /* List for errors generated on VME */ - struct list_head devices; /* List of devices on this bridge */ + /* List for registered errors handlers */ + struct list_head vme_error_handlers; + /* List of devices on this bridge */ + struct list_head devices; /* Bridge Info - XXX Move to private structure? */ struct device *parent; /* Parent device (eg. pdev->dev for PCI) */ @@ -168,13 +173,13 @@ struct vme_bridge { void vme_bus_error_handler(struct vme_bridge *bridge, unsigned long long address, int am); -struct vme_bus_error *vme_find_error(struct vme_bridge *bridge, u32 aspace, - unsigned long long address, size_t count); -void vme_clear_errors(struct vme_bridge *bridge, u32 aspace, - unsigned long long address, size_t count); void vme_irq_handler(struct vme_bridge *, int, int); int vme_register_bridge(struct vme_bridge *); void vme_unregister_bridge(struct vme_bridge *); +struct vme_error_handler *vme_register_error_handler( + struct vme_bridge *bridge, u32 aspace, + unsigned long long address, size_t len); +void vme_unregister_error_handler(struct vme_error_handler *handler); #endif /* _VME_BRIDGE_H_ */ -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/