Re: [PATCH v2 1/4] nfs/blocklayout: Fix premature PR key unregistration

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sun, Jun 23, 2024 at 09:36:27AM +0200, Christoph Hellwig wrote:
> On Sat, Jun 22, 2024 at 01:26:10PM -0400, Chuck Lever wrote:
> > This patch currently adds the pr_reg callback to
> > bl_find_get_deviceid(), which has no visibility of the volume
> > hierarchy. Where should the registration be done instead? I'm
> > missing something.
> 
> Something like the patch below (untested Sunday morning coding) should
> do the trick:
> 
> diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
> index 947b2c52344097..6db54b215066e0 100644
> --- a/fs/nfs/blocklayout/blocklayout.c
> +++ b/fs/nfs/blocklayout/blocklayout.c
> @@ -564,34 +564,32 @@ bl_find_get_deviceid(struct nfs_server *server,
>  		gfp_t gfp_mask)
>  {
>  	struct nfs4_deviceid_node *node;
> -	struct pnfs_block_dev *d;
> -	unsigned long start, end;
> +	int err = -ENODEV;
>  
>  retry:
>  	node = nfs4_find_get_deviceid(server, id, cred, gfp_mask);
>  	if (!node)
>  		return ERR_PTR(-ENODEV);
>  
> -	if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags))
> -		goto transient;
> +	if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags)) {
> +		unsigned long end = jiffies;
> +		unsigned long start = end - PNFS_DEVICE_RETRY_TIMEOUT;
>  
> -	d = container_of(node, struct pnfs_block_dev, node);
> -	if (d->pr_register)
> -		if (!d->pr_register(d))
> -			goto out_put;
> -	return node;
> -
> -transient:
> -	end = jiffies;
> -	start = end - PNFS_DEVICE_RETRY_TIMEOUT;
> -	if (!time_in_range(node->timestamp_unavailable, start, end)) {
> -		nfs4_delete_deviceid(node->ld, node->nfs_client, id);
> -		goto retry;
> +		if (!time_in_range(node->timestamp_unavailable, start, end)) {
> +			nfs4_delete_deviceid(node->ld, node->nfs_client, id);
> +			goto retry;
> +		}
> +		goto out_put;
>  	}
>  
> +	err = bl_register_dev(container_of(node, struct pnfs_block_dev, node));
> +	if (err)
> +		goto out_put;
> +	return node;
> +
>  out_put:
>  	nfs4_put_deviceid_node(node);
> -	return ERR_PTR(-ENODEV);
> +	return ERR_PTR(err);
>  }
>  
>  static int
> diff --git a/fs/nfs/blocklayout/blocklayout.h b/fs/nfs/blocklayout/blocklayout.h
> index cc788e8ce90933..7efbef9d10dba8 100644
> --- a/fs/nfs/blocklayout/blocklayout.h
> +++ b/fs/nfs/blocklayout/blocklayout.h
> @@ -104,6 +104,7 @@ struct pnfs_block_dev {
>  	u64				start;
>  	u64				len;
>  
> +	enum pnfs_block_volume_type	type;
>  	u32				nr_children;
>  	struct pnfs_block_dev		*children;
>  	u64				chunk_size;
> @@ -116,7 +117,6 @@ struct pnfs_block_dev {
>  
>  	bool (*map)(struct pnfs_block_dev *dev, u64 offset,
>  			struct pnfs_block_dev_map *map);
> -	bool (*pr_register)(struct pnfs_block_dev *dev);
>  };
>  
>  /* pnfs_block_dev flag bits */
> @@ -178,6 +178,7 @@ struct bl_msg_hdr {
>  #define BL_DEVICE_REQUEST_ERR          0x2 /* User level process fails */
>  
>  /* dev.c */
> +int bl_register_dev(struct pnfs_block_dev *d);
>  struct nfs4_deviceid_node *bl_alloc_deviceid_node(struct nfs_server *server,
>  		struct pnfs_device *pdev, gfp_t gfp_mask);
>  void bl_free_deviceid_node(struct nfs4_deviceid_node *d);
> diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c
> index 16fb64d4af31db..72e061e87e145a 100644
> --- a/fs/nfs/blocklayout/dev.c
> +++ b/fs/nfs/blocklayout/dev.c
> @@ -13,9 +13,74 @@
>  
>  #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
>  
> +static void bl_unregister_scsi(struct pnfs_block_dev *dev)
> +{
> +	struct block_device *bdev = file_bdev(dev->bdev_file);
> +	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
> +
> +	if (!test_and_clear_bit(PNFS_BDEV_REGISTERED, &dev->flags))
> +		return;
> +
> +	if (ops->pr_register(bdev, dev->pr_key, 0, false))
> +		pr_err("failed to unregister PR key.\n");
> +}
> +
> +static bool bl_register_scsi(struct pnfs_block_dev *dev)
> +{
> +	struct block_device *bdev = file_bdev(dev->bdev_file);
> +	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
> +	int status;
> +
> +	if (test_and_set_bit(PNFS_BDEV_REGISTERED, &dev->flags))
> +		return true;
> +
> +	status = ops->pr_register(bdev, 0, dev->pr_key, true);
> +	if (status) {
> +		pr_err("pNFS: failed to register key for block device %s.",
> +		       bdev->bd_disk->disk_name);
> +		return false;
> +	}
> +	return true;
> +}
> +
> +static void bl_unregister_dev(struct pnfs_block_dev *dev)
> +{
> +	if (dev->nr_children) {
> +		for (u32 i = 0; i < dev->nr_children; i++)
> +			bl_unregister_dev(&dev->children[i]);
> +		return;
> +	}
> +
> +	if (dev->type == PNFS_BLOCK_VOLUME_SCSI)
> +		bl_unregister_scsi(dev);
> +}
> +
> +int bl_register_dev(struct pnfs_block_dev *dev)
> +{
> +	if (dev->nr_children) {
> +		for (u32 i = 0; i < dev->nr_children; i++) {
> +			int ret = bl_register_dev(&dev->children[i]);
> +
> +			if (ret) {
> +				while (i > 0)
> +					bl_unregister_dev(&dev->children[--i]);
> +				return ret;
> +			}
> +		}
> +
> +		return 0;
> +	}
> +
> +	if (dev->type == PNFS_BLOCK_VOLUME_SCSI)
> +		return bl_register_scsi(dev);
> +	return 0;
> +}
> +
>  static void
>  bl_free_device(struct pnfs_block_dev *dev)
>  {
> +	bl_unregister_dev(dev);
> +
>  	if (dev->nr_children) {
>  		int i;
>  
> @@ -23,17 +88,6 @@ bl_free_device(struct pnfs_block_dev *dev)
>  			bl_free_device(&dev->children[i]);
>  		kfree(dev->children);
>  	} else {
> -		if (test_and_clear_bit(PNFS_BDEV_REGISTERED, &dev->flags)) {
> -			struct block_device *bdev = file_bdev(dev->bdev_file);
> -			const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
> -			int error;
> -
> -			error = ops->pr_register(file_bdev(dev->bdev_file),
> -				dev->pr_key, 0, false);
> -			if (error)
> -				pr_err("failed to unregister PR key.\n");
> -		}
> -
>  		if (dev->bdev_file)
>  			fput(dev->bdev_file);
>  	}
> @@ -226,30 +280,6 @@ static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
>  	return true;
>  }
>  
> -/**
> - * bl_pr_register_scsi - Register a SCSI PR key for @d
> - * @dev: pNFS block device, key to register is already in @d->pr_key
> - *
> - * Returns true if the device's PR key is registered, otherwise false.
> - */
> -static bool bl_pr_register_scsi(struct pnfs_block_dev *dev)
> -{
> -	struct block_device *bdev = file_bdev(dev->bdev_file);
> -	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
> -	int status;
> -
> -	if (test_and_set_bit(PNFS_BDEV_REGISTERED, &dev->flags))
> -		return true;
> -
> -	status = ops->pr_register(bdev, 0, dev->pr_key, true);
> -	if (status) {
> -		pr_err("pNFS: failed to register key for block device %s.",
> -		       bdev->bd_disk->disk_name);
> -		return false;
> -	}
> -	return true;
> -}
> -
>  static int
>  bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
>  		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
> @@ -392,7 +422,6 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
>  		goto out_blkdev_put;
>  	}
>  
> -	d->pr_register = bl_pr_register_scsi;
>  	return 0;
>  
>  out_blkdev_put:
> @@ -478,7 +507,9 @@ static int
>  bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
>  		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
>  {
> -	switch (volumes[idx].type) {
> +	d->type = volumes[idx].type;
> +
> +	switch (d->type) {
>  	case PNFS_BLOCK_VOLUME_SIMPLE:
>  		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
>  	case PNFS_BLOCK_VOLUME_SLICE:
> @@ -490,7 +521,7 @@ bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
>  	case PNFS_BLOCK_VOLUME_SCSI:
>  		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
>  	default:
> -		dprintk("unsupported volume type: %d\n", volumes[idx].type);
> +		dprintk("unsupported volume type: %d\n", d->type);
>  		return -EIO;
>  	}
>  }

Thanks. I've applied this as a separate patch (I can squash it into
1/4 once it passes testing). The first write I/O segfaults at L143
in do_add_page_to_bio() :

 142         if (!offset_in_map(disk_addr, map)) {                       
 143                 if (!dev->map(dev, disk_addr, map) || !offset_in_map(disk_addr, map))
 144                         return ERR_PTR(-EIO);

I'm looking into it.


-- 
Chuck Lever




[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux