From 4d936ec1fdc1541cd6d59d21ddb8b9386e2fcc4c Mon Sep 17 00:00:00 2001 From: "Michael J. Evans" Date: Tue, 16 Oct 2007 23:30:52 -0700 Subject: [PATCH] md: software Raid autodetect dev list not array In current release kernels the md module (Software RAID) uses a static array (dev_t[128]) to store partition/device info temporarily for autostart. I discovered this (and that the devices are added as disks/partitions are discovered at boot) while I was debugging why only one of my MD arrays would come up whole, while all the others were short a disk. I eventually discovered that it was enumerating through all of 9 of my 11 hds (2 had only 4 partitions apiece) while the other 9 have 15 partitions (I wanted 64 per drive...). The last partition of the 8th drive in my 9 drive raid 5 sets wasn't added, thus making the final md array short both a parity and data disk, and it was started later, elsewhere. This patch replaces that static array with a list. [akpm@linux-foundation.org: removed unused var] Signed-off-by: Michael J. Evans Cc: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/md.c | 42 +++++++++++++++++++++++++++++++++--------- 1 file changed, 33 insertions(+), 9 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 0dc563d76b39..f173ace1f8fb 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5770,26 +5770,47 @@ static int __init md_init(void) * Searches all registered partitions for autorun RAID arrays * at boot time. */ -static dev_t detected_devices[128]; -static int dev_cnt; + +static LIST_HEAD(all_detected_devices); +struct detected_devices_node { + struct list_head list; + dev_t dev; +}; void md_autodetect_dev(dev_t dev) { - if (dev_cnt >= 0 && dev_cnt < 127) - detected_devices[dev_cnt++] = dev; + struct detected_devices_node *node_detected_dev; + + node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL); + if (node_detected_dev) { + node_detected_dev->dev = dev; + list_add_tail(&node_detected_dev->list, &all_detected_devices); + } else { + printk(KERN_CRIT "md: md_autodetect_dev: kzalloc failed" + ", skipping dev(%d,%d)\n", MAJOR(dev), MINOR(dev)); + } } static void autostart_arrays(int part) { mdk_rdev_t *rdev; - int i; + struct detected_devices_node *node_detected_dev; + dev_t dev; + int i_scanned, i_passed; - printk(KERN_INFO "md: Autodetecting RAID arrays.\n"); + i_scanned = 0; + i_passed = 0; - for (i = 0; i < dev_cnt; i++) { - dev_t dev = detected_devices[i]; + printk(KERN_INFO "md: Autodetecting RAID arrays.\n"); + while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) { + i_scanned++; + node_detected_dev = list_entry(all_detected_devices.next, + struct detected_devices_node, list); + list_del(&node_detected_dev->list); + dev = node_detected_dev->dev; + kfree(node_detected_dev); rdev = md_import_device(dev,0, 90); if (IS_ERR(rdev)) continue; @@ -5799,8 +5820,11 @@ static void autostart_arrays(int part) continue; } list_add(&rdev->same_set, &pending_raid_disks); + i_passed++; } - dev_cnt = 0; + + printk(KERN_INFO "md: Scanned %d and added %d devices.\n", + i_scanned, i_passed); autorun_devices(part); } -- 2.20.1