From 646cdf0083e3d4a9b995f37b72c3c8a22d9307de Mon Sep 17 00:00:00 2001 From: Tomas Henzl Date: Wed, 9 Jul 2014 17:21:01 +0530 Subject: [PATCH] pm8001: add a new spinlock to protect the CCB Patch adds a new spinlock to protect the ccb management. It may happen that concurrent threads become the same tag value from the 'alloc' function', the spinlock prevents this situation. Signed-off-by: Tomas Henzl Acked-by: Suresh Thiagarajan Acked-by: Jack Wang Signed-off-by: Christoph Hellwig --- drivers/scsi/pm8001/pm8001_init.c | 1 + drivers/scsi/pm8001/pm8001_sas.c | 7 ++++++- drivers/scsi/pm8001/pm8001_sas.h | 1 + 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c index aad060aa3c0c..acef7d6a5790 100644 --- a/drivers/scsi/pm8001/pm8001_init.c +++ b/drivers/scsi/pm8001/pm8001_init.c @@ -246,6 +246,7 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha, { int i; spin_lock_init(&pm8001_ha->lock); + spin_lock_init(&pm8001_ha->bitmap_lock); PM8001_INIT_DBG(pm8001_ha, pm8001_printk("pm8001_alloc: PHY:%x\n", pm8001_ha->chip->n_phy)); diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c index be55859042cd..34cea8291772 100644 --- a/drivers/scsi/pm8001/pm8001_sas.c +++ b/drivers/scsi/pm8001/pm8001_sas.c @@ -77,11 +77,16 @@ inline int pm8001_tag_alloc(struct pm8001_hba_info *pm8001_ha, u32 *tag_out) { unsigned int tag; void *bitmap = pm8001_ha->tags; + unsigned long flags; + spin_lock_irqsave(&pm8001_ha->bitmap_lock, flags); tag = find_first_zero_bit(bitmap, pm8001_ha->tags_num); - if (tag >= pm8001_ha->tags_num) + if (tag >= pm8001_ha->tags_num) { + spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags); return -SAS_QUEUE_FULL; + } set_bit(tag, bitmap); + spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags); *tag_out = tag; return 0; } diff --git a/drivers/scsi/pm8001/pm8001_sas.h b/drivers/scsi/pm8001/pm8001_sas.h index 14106adec009..f6b2ac59dae4 100644 --- a/drivers/scsi/pm8001/pm8001_sas.h +++ b/drivers/scsi/pm8001/pm8001_sas.h @@ -475,6 +475,7 @@ struct pm8001_hba_info { struct list_head list; unsigned long flags; spinlock_t lock;/* host-wide lock */ + spinlock_t bitmap_lock; struct pci_dev *pdev;/* our device */ struct device *dev; struct pm8001_hba_memspace io_mem[6];