From 1f7466c6b428fa52504e85c2df43aa8641f9294e Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Tue, 1 Aug 2017 16:05:53 +0530 Subject: [PATCH] mailbox: bcm-flexrm-mailbox: Use bitmap instead of IDA Currently, we are using IDA library for managing IDs on a FlexRM ring. The IDA library dynamically allocates memory for underlying data structures which can cause potential locking issue when allocating/free IDs from flexrm_new_request() and flexrm_process_completions(). To tackle this, we replace use of IDA with bitmap for each FlexRM ring and also protect the bitmap with FlexRM ring lock. Signed-off-by: Anup Patel Signed-off-by: Jassi Brar --- drivers/mailbox/bcm-flexrm-mailbox.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/drivers/mailbox/bcm-flexrm-mailbox.c b/drivers/mailbox/bcm-flexrm-mailbox.c index 46ad305..9873818 100644 --- a/drivers/mailbox/bcm-flexrm-mailbox.c +++ b/drivers/mailbox/bcm-flexrm-mailbox.c @@ -18,13 +18,13 @@ #include #include #include +#include #include #include #include #include #include #include -#include #include #include #include @@ -265,7 +265,6 @@ struct flexrm_ring { cpumask_t irq_aff_hint; unsigned int msi_timer_val; unsigned int msi_count_threshold; - struct ida requests_ida; struct brcm_message *requests[RING_MAX_REQ_COUNT]; void *bd_base; dma_addr_t bd_dma_base; @@ -277,6 +276,7 @@ struct flexrm_ring { atomic_t msg_cmpl_count; /* Protected members */ spinlock_t lock; + DECLARE_BITMAP(requests_bmap, RING_MAX_REQ_COUNT); struct brcm_message *last_pending_msg; u32 cmpl_read_offset; }; @@ -994,10 +994,10 @@ static int flexrm_new_request(struct flexrm_ring *ring, msg->error = 0; /* If no requests possible then save data pointer and goto done. */ - reqid = ida_simple_get(&ring->requests_ida, 0, - RING_MAX_REQ_COUNT, GFP_KERNEL); + spin_lock_irqsave(&ring->lock, flags); + reqid = bitmap_find_free_region(ring->requests_bmap, + RING_MAX_REQ_COUNT, 0); if (reqid < 0) { - spin_lock_irqsave(&ring->lock, flags); if (batch_msg) ring->last_pending_msg = batch_msg; else @@ -1005,13 +1005,16 @@ static int flexrm_new_request(struct flexrm_ring *ring, spin_unlock_irqrestore(&ring->lock, flags); return 0; } + spin_unlock_irqrestore(&ring->lock, flags); ring->requests[reqid] = msg; /* Do DMA mappings for the message */ ret = flexrm_dma_map(ring->mbox->dev, msg); if (ret < 0) { ring->requests[reqid] = NULL; - ida_simple_remove(&ring->requests_ida, reqid); + spin_lock_irqsave(&ring->lock, flags); + bitmap_release_region(ring->requests_bmap, reqid, 0); + spin_unlock_irqrestore(&ring->lock, flags); return ret; } @@ -1088,7 +1091,9 @@ exit: if (exit_cleanup) { flexrm_dma_unmap(ring->mbox->dev, msg); ring->requests[reqid] = NULL; - ida_simple_remove(&ring->requests_ida, reqid); + spin_lock_irqsave(&ring->lock, flags); + bitmap_release_region(ring->requests_bmap, reqid, 0); + spin_unlock_irqrestore(&ring->lock, flags); } return ret; @@ -1163,7 +1168,9 @@ static int flexrm_process_completions(struct flexrm_ring *ring) /* Release reqid for recycling */ ring->requests[reqid] = NULL; - ida_simple_remove(&ring->requests_ida, reqid); + spin_lock_irqsave(&ring->lock, flags); + bitmap_release_region(ring->requests_bmap, reqid, 0); + spin_unlock_irqrestore(&ring->lock, flags); /* Unmap DMA mappings */ flexrm_dma_unmap(ring->mbox->dev, msg); @@ -1414,7 +1421,6 @@ static void flexrm_shutdown(struct mbox_chan *chan) /* Release reqid for recycling */ ring->requests[reqid] = NULL; - ida_simple_remove(&ring->requests_ida, reqid); /* Unmap DMA mappings */ flexrm_dma_unmap(ring->mbox->dev, msg); @@ -1424,6 +1430,9 @@ static void flexrm_shutdown(struct mbox_chan *chan) mbox_chan_received_data(chan, msg); } + /* Clear requests bitmap */ + bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT); + /* Release IRQ */ if (ring->irq_requested) { irq_set_affinity_hint(ring->irq, NULL); @@ -1581,7 +1590,6 @@ static int flexrm_mbox_probe(struct platform_device *pdev) ring->irq_requested = false; ring->msi_timer_val = MSI_TIMER_VAL_MASK; ring->msi_count_threshold = 0x1; - ida_init(&ring->requests_ida); memset(ring->requests, 0, sizeof(ring->requests)); ring->bd_base = NULL; ring->bd_dma_base = 0; @@ -1590,6 +1598,7 @@ static int flexrm_mbox_probe(struct platform_device *pdev) atomic_set(&ring->msg_send_count, 0); atomic_set(&ring->msg_cmpl_count, 0); spin_lock_init(&ring->lock); + bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT); ring->last_pending_msg = NULL; ring->cmpl_read_offset = 0; } @@ -1701,9 +1710,7 @@ fail: static int flexrm_mbox_remove(struct platform_device *pdev) { - int index; struct device *dev = &pdev->dev; - struct flexrm_ring *ring; struct flexrm_mbox *mbox = platform_get_drvdata(pdev); mbox_controller_unregister(&mbox->controller); @@ -1715,11 +1722,6 @@ static int flexrm_mbox_remove(struct platform_device *pdev) dma_pool_destroy(mbox->cmpl_pool); dma_pool_destroy(mbox->bd_pool); - for (index = 0; index < mbox->num_rings; index++) { - ring = &mbox->rings[index]; - ida_destroy(&ring->requests_ida); - } - return 0; } -- 2.7.4