Commit 0fe9f15e authored by Francois Romieu's avatar Francois Romieu
Browse files

via-velocity: separated struct allow wholesale copy during MTU changes. 



It should help people fix the bugs in my code :o)

Signed-off-by: default avatarFrancois Romieu <romieu@fr.zoreil.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 031cf19e

drivers/net/via-velocity.c

+87 −86
Original line number Diff line number Diff line
@@ -677,16 +677,16 @@ static void velocity_rx_reset(struct velocity_info *vptr) 
	struct mac_regs __iomem * regs = vptr->mac_regs;

	int i;



	vptr->rd_dirty = vptr->rd_filled = vptr->rd_curr = 0;

	vptr->rx.dirty = vptr->rx.filled = vptr->rx.curr = 0;



	/*

	 *	Init state, all RD entries belong to the NIC

	 */

	for (i = 0; i < vptr->options.numrx; ++i)

		vptr->rd_ring[i].rdesc0.len |= OWNED_BY_NIC;

		vptr->rx.ring[i].rdesc0.len |= OWNED_BY_NIC;



	writew(vptr->options.numrx, &regs->RBRDU);

	writel(vptr->rd_pool_dma, &regs->RDBaseLo);

	writel(vptr->rx.pool_dma, &regs->RDBaseLo);

	writew(0, &regs->RDIdx);

	writew(vptr->options.numrx - 1, &regs->RDCSize);

}
@@ -779,15 +779,15 @@ static void velocity_init_registers(struct velocity_info *vptr, 


		vptr->int_mask = INT_MASK_DEF;



		writel(vptr->rd_pool_dma, &regs->RDBaseLo);

		writel(vptr->rx.pool_dma, &regs->RDBaseLo);

		writew(vptr->options.numrx - 1, &regs->RDCSize);

		mac_rx_queue_run(regs);

		mac_rx_queue_wake(regs);



		writew(vptr->options.numtx - 1, &regs->TDCSize);



		for (i = 0; i < vptr->num_txq; i++) {

			writel(vptr->td_pool_dma[i], &regs->TDBaseLo[i]);

		for (i = 0; i < vptr->tx.numq; i++) {

			writel(vptr->tx.pool_dma[i], &regs->TDBaseLo[i]);

			mac_tx_queue_run(regs, i);

		}
@@ -1047,7 +1047,7 @@ static void __devinit velocity_init_info(struct pci_dev *pdev, 


	vptr->pdev = pdev;

	vptr->chip_id = info->chip_id;

	vptr->num_txq = info->txqueue;

	vptr->tx.numq = info->txqueue;

	vptr->multicast_limit = MCAM_SIZE;

	spin_lock_init(&vptr->lock);

	INIT_LIST_HEAD(&vptr->list);
@@ -1116,7 +1116,7 @@ static int velocity_init_rings(struct velocity_info *vptr) 
	 * pci_alloc_consistent() fulfills the requirement for 64 bytes

	 * alignment

	 */

	pool = pci_alloc_consistent(pdev, tx_ring_size * vptr->num_txq +

	pool = pci_alloc_consistent(pdev, tx_ring_size * vptr->tx.numq +

				    rx_ring_size, &pool_dma);

	if (!pool) {

		dev_err(&pdev->dev, "%s : DMA memory allocation failed.\n",
@@ -1124,15 +1124,15 @@ static int velocity_init_rings(struct velocity_info *vptr) 
		return -ENOMEM;

	}



	vptr->rd_ring = pool;

	vptr->rd_pool_dma = pool_dma;

	vptr->rx.ring = pool;

	vptr->rx.pool_dma = pool_dma;



	pool += rx_ring_size;

	pool_dma += rx_ring_size;



	for (i = 0; i < vptr->num_txq; i++) {

		vptr->td_rings[i] = pool;

		vptr->td_pool_dma[i] = pool_dma;

	for (i = 0; i < vptr->tx.numq; i++) {

		vptr->tx.rings[i] = pool;

		vptr->tx.pool_dma[i] = pool_dma;

		pool += tx_ring_size;

		pool_dma += tx_ring_size;

	}
@@ -1150,9 +1150,9 @@ static int velocity_init_rings(struct velocity_info *vptr) 
static void velocity_free_rings(struct velocity_info *vptr)

{

	const int size = vptr->options.numrx * sizeof(struct rx_desc) +

		vptr->options.numtx * sizeof(struct tx_desc) * vptr->num_txq;

		vptr->options.numtx * sizeof(struct tx_desc) * vptr->tx.numq;



	pci_free_consistent(vptr->pdev, size, vptr->rd_ring, vptr->rd_pool_dma);

	pci_free_consistent(vptr->pdev, size, vptr->rx.ring, vptr->rx.pool_dma);

}



static void velocity_give_many_rx_descs(struct velocity_info *vptr)
@@ -1164,44 +1164,44 @@ static void velocity_give_many_rx_descs(struct velocity_info *vptr) 
	 * RD number must be equal to 4X per hardware spec

	 * (programming guide rev 1.20, p.13)

	 */

	if (vptr->rd_filled < 4)

	if (vptr->rx.filled < 4)

		return;



	wmb();



	unusable = vptr->rd_filled & 0x0003;

	dirty = vptr->rd_dirty - unusable;

	for (avail = vptr->rd_filled & 0xfffc; avail; avail--) {

	unusable = vptr->rx.filled & 0x0003;

	dirty = vptr->rx.dirty - unusable;

	for (avail = vptr->rx.filled & 0xfffc; avail; avail--) {

		dirty = (dirty > 0) ? dirty - 1 : vptr->options.numrx - 1;

		vptr->rd_ring[dirty].rdesc0.len |= OWNED_BY_NIC;

		vptr->rx.ring[dirty].rdesc0.len |= OWNED_BY_NIC;

	}



	writew(vptr->rd_filled & 0xfffc, &regs->RBRDU);

	vptr->rd_filled = unusable;

	writew(vptr->rx.filled & 0xfffc, &regs->RBRDU);

	vptr->rx.filled = unusable;

}



static int velocity_rx_refill(struct velocity_info *vptr)

{

	int dirty = vptr->rd_dirty, done = 0;

	int dirty = vptr->rx.dirty, done = 0;



	do {

		struct rx_desc *rd = vptr->rd_ring + dirty;

		struct rx_desc *rd = vptr->rx.ring + dirty;



		/* Fine for an all zero Rx desc at init time as well */

		if (rd->rdesc0.len & OWNED_BY_NIC)

			break;



		if (!vptr->rd_info[dirty].skb) {

		if (!vptr->rx.info[dirty].skb) {

			if (velocity_alloc_rx_buf(vptr, dirty) < 0)

				break;

		}

		done++;

		dirty = (dirty < vptr->options.numrx - 1) ? dirty + 1 : 0;

	} while (dirty != vptr->rd_curr);

	} while (dirty != vptr->rx.curr);



	if (done) {

		vptr->rd_dirty = dirty;

		vptr->rd_filled += done;

		vptr->rx.dirty = dirty;

		vptr->rx.filled += done;

	}



	return done;
@@ -1209,7 +1209,7 @@ static int velocity_rx_refill(struct velocity_info *vptr) 


static void velocity_set_rxbufsize(struct velocity_info *vptr, int mtu)

{

	vptr->rx_buf_sz = (mtu <= ETH_DATA_LEN) ? PKT_BUF_SZ : mtu + 32;

	vptr->rx.buf_sz = (mtu <= ETH_DATA_LEN) ? PKT_BUF_SZ : mtu + 32;

}



/**
@@ -1224,12 +1224,12 @@ static int velocity_init_rd_ring(struct velocity_info *vptr) 
{

	int ret = -ENOMEM;



	vptr->rd_info = kcalloc(vptr->options.numrx,

	vptr->rx.info = kcalloc(vptr->options.numrx,

				sizeof(struct velocity_rd_info), GFP_KERNEL);

	if (!vptr->rd_info)

	if (!vptr->rx.info)

		goto out;



	vptr->rd_filled = vptr->rd_dirty = vptr->rd_curr = 0;

	vptr->rx.filled = vptr->rx.dirty = vptr->rx.curr = 0;



	if (velocity_rx_refill(vptr) != vptr->options.numrx) {

		VELOCITY_PRT(MSG_LEVEL_ERR, KERN_ERR
@@ -1255,18 +1255,18 @@ static void velocity_free_rd_ring(struct velocity_info *vptr) 
{

	int i;



	if (vptr->rd_info == NULL)

	if (vptr->rx.info == NULL)

		return;



	for (i = 0; i < vptr->options.numrx; i++) {

		struct velocity_rd_info *rd_info = &(vptr->rd_info[i]);

		struct rx_desc *rd = vptr->rd_ring + i;

		struct velocity_rd_info *rd_info = &(vptr->rx.info[i]);

		struct rx_desc *rd = vptr->rx.ring + i;



		memset(rd, 0, sizeof(*rd));



		if (!rd_info->skb)

			continue;

		pci_unmap_single(vptr->pdev, rd_info->skb_dma, vptr->rx_buf_sz,

		pci_unmap_single(vptr->pdev, rd_info->skb_dma, vptr->rx.buf_sz,

				 PCI_DMA_FROMDEVICE);

		rd_info->skb_dma = (dma_addr_t) NULL;
@@ -1274,8 +1274,8 @@ static void velocity_free_rd_ring(struct velocity_info *vptr) 
		rd_info->skb = NULL;

	}



	kfree(vptr->rd_info);

	vptr->rd_info = NULL;

	kfree(vptr->rx.info);

	vptr->rx.info = NULL;

}



/**
@@ -1293,19 +1293,19 @@ static int velocity_init_td_ring(struct velocity_info *vptr) 
	unsigned int j;



	/* Init the TD ring entries */

	for (j = 0; j < vptr->num_txq; j++) {

		curr = vptr->td_pool_dma[j];

	for (j = 0; j < vptr->tx.numq; j++) {

		curr = vptr->tx.pool_dma[j];



		vptr->td_infos[j] = kcalloc(vptr->options.numtx,

		vptr->tx.infos[j] = kcalloc(vptr->options.numtx,

					    sizeof(struct velocity_td_info),

					    GFP_KERNEL);

		if (!vptr->td_infos[j])	{

		if (!vptr->tx.infos[j])	{

			while(--j >= 0)

				kfree(vptr->td_infos[j]);

				kfree(vptr->tx.infos[j]);

			return -ENOMEM;

		}



		vptr->td_tail[j] = vptr->td_curr[j] = vptr->td_used[j] = 0;

		vptr->tx.tail[j] = vptr->tx.curr[j] = vptr->tx.used[j] = 0;

	}

	return 0;

}
@@ -1317,7 +1317,7 @@ static int velocity_init_td_ring(struct velocity_info *vptr) 
static void velocity_free_td_ring_entry(struct velocity_info *vptr,

							 int q, int n)

{

	struct velocity_td_info * td_info = &(vptr->td_infos[q][n]);

	struct velocity_td_info * td_info = &(vptr->tx.infos[q][n]);

	int i;



	if (td_info == NULL)
@@ -1349,15 +1349,15 @@ static void velocity_free_td_ring(struct velocity_info *vptr) 
{

	int i, j;



	for (j = 0; j < vptr->num_txq; j++) {

		if (vptr->td_infos[j] == NULL)

	for (j = 0; j < vptr->tx.numq; j++) {

		if (vptr->tx.infos[j] == NULL)

			continue;

		for (i = 0; i < vptr->options.numtx; i++) {

			velocity_free_td_ring_entry(vptr, j, i);



		}

		kfree(vptr->td_infos[j]);

		vptr->td_infos[j] = NULL;

		kfree(vptr->tx.infos[j]);

		vptr->tx.infos[j] = NULL;

	}

}
@@ -1374,13 +1374,13 @@ static void velocity_free_td_ring(struct velocity_info *vptr) 
static int velocity_rx_srv(struct velocity_info *vptr, int status)

{

	struct net_device_stats *stats = &vptr->stats;

	int rd_curr = vptr->rd_curr;

	int rd_curr = vptr->rx.curr;

	int works = 0;



	do {

		struct rx_desc *rd = vptr->rd_ring + rd_curr;

		struct rx_desc *rd = vptr->rx.ring + rd_curr;



		if (!vptr->rd_info[rd_curr].skb)

		if (!vptr->rx.info[rd_curr].skb)

			break;



		if (rd->rdesc0.len & OWNED_BY_NIC)
@@ -1412,7 +1412,7 @@ static int velocity_rx_srv(struct velocity_info *vptr, int status) 
			rd_curr = 0;

	} while (++works <= 15);



	vptr->rd_curr = rd_curr;

	vptr->rx.curr = rd_curr;



	if ((works > 0) && (velocity_rx_refill(vptr) > 0))

		velocity_give_many_rx_descs(vptr);
@@ -1510,8 +1510,8 @@ static int velocity_receive_frame(struct velocity_info *vptr, int idx) 
{

	void (*pci_action)(struct pci_dev *, dma_addr_t, size_t, int);

	struct net_device_stats *stats = &vptr->stats;

	struct velocity_rd_info *rd_info = &(vptr->rd_info[idx]);

	struct rx_desc *rd = &(vptr->rd_ring[idx]);

	struct velocity_rd_info *rd_info = &(vptr->rx.info[idx]);

	struct rx_desc *rd = &(vptr->rx.ring[idx]);

	int pkt_len = le16_to_cpu(rd->rdesc0.len) & 0x3fff;

	struct sk_buff *skb;
@@ -1527,7 +1527,7 @@ static int velocity_receive_frame(struct velocity_info *vptr, int idx) 
	skb = rd_info->skb;



	pci_dma_sync_single_for_cpu(vptr->pdev, rd_info->skb_dma,

				    vptr->rx_buf_sz, PCI_DMA_FROMDEVICE);

				    vptr->rx.buf_sz, PCI_DMA_FROMDEVICE);



	/*

	 *	Drop frame not meeting IEEE 802.3
@@ -1550,7 +1550,7 @@ static int velocity_receive_frame(struct velocity_info *vptr, int idx) 
		rd_info->skb = NULL;

	}



	pci_action(vptr->pdev, rd_info->skb_dma, vptr->rx_buf_sz,

	pci_action(vptr->pdev, rd_info->skb_dma, vptr->rx.buf_sz,

		   PCI_DMA_FROMDEVICE);



	skb_put(skb, pkt_len - 4);
@@ -1580,10 +1580,10 @@ static int velocity_receive_frame(struct velocity_info *vptr, int idx) 


static int velocity_alloc_rx_buf(struct velocity_info *vptr, int idx)

{

	struct rx_desc *rd = &(vptr->rd_ring[idx]);

	struct velocity_rd_info *rd_info = &(vptr->rd_info[idx]);

	struct rx_desc *rd = &(vptr->rx.ring[idx]);

	struct velocity_rd_info *rd_info = &(vptr->rx.info[idx]);



	rd_info->skb = netdev_alloc_skb(vptr->dev, vptr->rx_buf_sz + 64);

	rd_info->skb = dev_alloc_skb(vptr->rx.buf_sz + 64);

	if (rd_info->skb == NULL)

		return -ENOMEM;
@@ -1592,14 +1592,15 @@ static int velocity_alloc_rx_buf(struct velocity_info *vptr, int idx) 
	 *	64byte alignment.

	 */

	skb_reserve(rd_info->skb, (unsigned long) rd_info->skb->data & 63);

	rd_info->skb_dma = pci_map_single(vptr->pdev, rd_info->skb->data, vptr->rx_buf_sz, PCI_DMA_FROMDEVICE);

	rd_info->skb_dma = pci_map_single(vptr->pdev, rd_info->skb->data,

					vptr->rx.buf_sz, PCI_DMA_FROMDEVICE);



	/*

	 *	Fill in the descriptor to match

	 */



	*((u32 *) & (rd->rdesc0)) = 0;

	rd->size = cpu_to_le16(vptr->rx_buf_sz) | RX_INTEN;

	rd->size = cpu_to_le16(vptr->rx.buf_sz) | RX_INTEN;

	rd->pa_low = cpu_to_le32(rd_info->skb_dma);

	rd->pa_high = 0;

	return 0;
@@ -1625,15 +1626,15 @@ static int velocity_tx_srv(struct velocity_info *vptr, u32 status) 
	struct velocity_td_info *tdinfo;

	struct net_device_stats *stats = &vptr->stats;



	for (qnum = 0; qnum < vptr->num_txq; qnum++) {

		for (idx = vptr->td_tail[qnum]; vptr->td_used[qnum] > 0;

	for (qnum = 0; qnum < vptr->tx.numq; qnum++) {

		for (idx = vptr->tx.tail[qnum]; vptr->tx.used[qnum] > 0;

			idx = (idx + 1) % vptr->options.numtx) {



			/*

			 *	Get Tx Descriptor

			 */

			td = &(vptr->td_rings[qnum][idx]);

			tdinfo = &(vptr->td_infos[qnum][idx]);

			td = &(vptr->tx.rings[qnum][idx]);

			tdinfo = &(vptr->tx.infos[qnum][idx]);



			if (td->tdesc0.len & OWNED_BY_NIC)

				break;
@@ -1657,9 +1658,9 @@ static int velocity_tx_srv(struct velocity_info *vptr, u32 status) 
				stats->tx_bytes += tdinfo->skb->len;

			}

			velocity_free_tx_buf(vptr, tdinfo);

			vptr->td_used[qnum]--;

			vptr->tx.used[qnum]--;

		}

		vptr->td_tail[qnum] = idx;

		vptr->tx.tail[qnum] = idx;



		if (AVAIL_TD(vptr, qnum) < 1) {

			full = 1;
@@ -2056,9 +2057,9 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) 


	spin_lock_irqsave(&vptr->lock, flags);



	index = vptr->td_curr[qnum];

	td_ptr = &(vptr->td_rings[qnum][index]);

	tdinfo = &(vptr->td_infos[qnum][index]);

	index = vptr->tx.curr[qnum];

	td_ptr = &(vptr->tx.rings[qnum][index]);

	tdinfo = &(vptr->tx.infos[qnum][index]);



	td_ptr->tdesc1.TCR = TCR0_TIC;

	td_ptr->td_buf[0].size &= ~TD_QUEUE;
@@ -2071,9 +2072,9 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) 
			skb_copy_from_linear_data(skb, tdinfo->buf, skb->len);

			tdinfo->skb_dma[0] = tdinfo->buf_dma;

			td_ptr->tdesc0.len = len;

			td_ptr->td_buf[0].pa_low = cpu_to_le32(tdinfo->skb_dma[0]);

			td_ptr->td_buf[0].pa_high = 0;

			td_ptr->td_buf[0].size = len;	/* queue is 0 anyway */

			td_ptr->tx.buf[0].pa_low = cpu_to_le32(tdinfo->skb_dma[0]);

			td_ptr->tx.buf[0].pa_high = 0;

			td_ptr->tx.buf[0].size = len;	/* queue is 0 anyway */

			tdinfo->nskb_dma = 1;

		} else {

			int i = 0;
@@ -2084,9 +2085,9 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) 
			td_ptr->tdesc0.len = len;



			/* FIXME: support 48bit DMA later */

			td_ptr->td_buf[i].pa_low = cpu_to_le32(tdinfo->skb_dma);

			td_ptr->td_buf[i].pa_high = 0;

			td_ptr->td_buf[i].size = cpu_to_le16(skb_headlen(skb));

			td_ptr->tx.buf[i].pa_low = cpu_to_le32(tdinfo->skb_dma);

			td_ptr->tx.buf[i].pa_high = 0;

			td_ptr->tx.buf[i].size = cpu_to_le16(skb_headlen(skb));



			for (i = 0; i < nfrags; i++) {

				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
@@ -2094,9 +2095,9 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) 


				tdinfo->skb_dma[i + 1] = pci_map_single(vptr->pdev, addr, frag->size, PCI_DMA_TODEVICE);



				td_ptr->td_buf[i + 1].pa_low = cpu_to_le32(tdinfo->skb_dma[i + 1]);

				td_ptr->td_buf[i + 1].pa_high = 0;

				td_ptr->td_buf[i + 1].size = cpu_to_le16(frag->size);

				td_ptr->tx.buf[i + 1].pa_low = cpu_to_le32(tdinfo->skb_dma[i + 1]);

				td_ptr->tx.buf[i + 1].pa_high = 0;

				td_ptr->tx.buf[i + 1].size = cpu_to_le16(frag->size);

			}

			tdinfo->nskb_dma = i - 1;

		}
@@ -2142,13 +2143,13 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) 
		if (prev < 0)

			prev = vptr->options.numtx - 1;

		td_ptr->tdesc0.len |= OWNED_BY_NIC;

		vptr->td_used[qnum]++;

		vptr->td_curr[qnum] = (index + 1) % vptr->options.numtx;

		vptr->tx.used[qnum]++;

		vptr->tx.curr[qnum] = (index + 1) % vptr->options.numtx;



		if (AVAIL_TD(vptr, qnum) < 1)

			netif_stop_queue(dev);



		td_ptr = &(vptr->td_rings[qnum][prev]);

		td_ptr = &(vptr->tx.rings[qnum][prev]);

		td_ptr->td_buf[0].size |= TD_QUEUE;

		mac_tx_queue_wake(vptr->mac_regs, qnum);

	}
@@ -3405,8 +3406,8 @@ static int velocity_resume(struct pci_dev *pdev) 


	velocity_tx_srv(vptr, 0);



	for (i = 0; i < vptr->num_txq; i++) {

		if (vptr->td_used[i]) {

	for (i = 0; i < vptr->tx.numq; i++) {

		if (vptr->tx.used[i]) {

			mac_tx_queue_wake(vptr->mac_regs, i);

		}

	}

drivers/net/via-velocity.h

+27 −23
Original line number Diff line number Diff line
@@ -1494,6 +1494,10 @@ struct velocity_opt { 
	u32 flags;

};



#define AVAIL_TD(p,q)   ((p)->options.numtx-((p)->tx.used[(q)]))



#define GET_RD_BY_IDX(vptr, idx)   (vptr->rd_ring[idx])



struct velocity_info {

	struct list_head list;
@@ -1501,9 +1505,6 @@ struct velocity_info { 
	struct net_device *dev;

	struct net_device_stats stats;



	dma_addr_t rd_pool_dma;

	dma_addr_t td_pool_dma[TX_QUEUE_NO];



	struct vlan_group    *vlgrp;

	u8 ip_addr[4];

	enum chip_type chip_id;
@@ -1512,25 +1513,29 @@ struct velocity_info { 
	unsigned long memaddr;

	unsigned long ioaddr;



	u8 rev_id;



#define AVAIL_TD(p,q)   ((p)->options.numtx-((p)->td_used[(q)]))

	struct tx_info {

		int numq;



		/* FIXME: the locality of the data seems rather poor. */

		int used[TX_QUEUE_NO];

		int curr[TX_QUEUE_NO];

		int tail[TX_QUEUE_NO];

		struct tx_desc *rings[TX_QUEUE_NO];

		struct velocity_td_info *infos[TX_QUEUE_NO];

		dma_addr_t pool_dma[TX_QUEUE_NO];

	} tx;



	struct rx_info {

		int buf_sz;



		int dirty;

		int curr;

		u32 filled;

		struct rx_desc *ring;

		struct velocity_rd_info *info;	/* It's an array */

		dma_addr_t pool_dma;

	} rx;



	int num_txq;



	volatile int td_used[TX_QUEUE_NO];

	int td_curr[TX_QUEUE_NO];

	int td_tail[TX_QUEUE_NO];

	struct tx_desc *td_rings[TX_QUEUE_NO];

	struct velocity_td_info *td_infos[TX_QUEUE_NO];



	int rd_curr;

	int rd_dirty;

	u32 rd_filled;

	struct rx_desc *rd_ring;

	struct velocity_rd_info *rd_info;	/* It's an array */



#define GET_RD_BY_IDX(vptr, idx)   (vptr->rd_ring[idx])

	u32 mib_counter[MAX_HW_MIB_COUNTER];

	struct velocity_opt options;
@@ -1538,7 +1543,6 @@ struct velocity_info { 


	u32 flags;



	int rx_buf_sz;

	u32 mii_status;

	u32 phy_id;

	int multicast_limit;
@@ -1554,8 +1558,8 @@ struct velocity_info { 
	struct velocity_context context;



	u32 ticks;

	u32 rx_bytes;



	u8 rev_id;

};



/**

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