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Message-ID: <7881ee36-89f6-3ba9-f4ac-7c4e614728dd@foss.st.com>
Date:   Thu, 30 Jun 2022 18:36:45 +0200
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Subject: Re: [PATCH 1/2] remoteproc: core: Introduce rproc_del_carveout
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To:     Chris Lew <quic_clew@quicinc.com>, <bjorn.andersson@linaro.org>,
        <mathieu.poirier@linaro.org>
CC:     <linux-remoteproc@vger.kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <1654888985-3846-1-git-send-email-quic_clew@quicinc.com>
 <1654888985-3846-2-git-send-email-quic_clew@quicinc.com>
From:   Arnaud POULIQUEN <arnaud.pouliquen@foss.st.com>
In-Reply-To: <1654888985-3846-2-git-send-email-quic_clew@quicinc.com>
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Hi,

On 6/10/22 21:23, Chris Lew wrote:
> To mirror the exported rproc_add_carveout(), add a rproc_del_carveout()
> so memory carveout resources added by devices outside of remoteproc can
> manage the resource lifetime more accurately.
> 
> Signed-off-by: Chris Lew <quic_clew@quicinc.com>
> ---
>  drivers/remoteproc/remoteproc_core.c | 20 ++++++++++++++++++++
>  include/linux/remoteproc.h           |  1 +
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 02a04ab34a23..ee71fccae970 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1001,6 +1001,26 @@ void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem)
>  EXPORT_SYMBOL(rproc_add_carveout);
>  
>  /**
> + * rproc_del_carveout() - remove an allocated carveout region
> + * @rproc: rproc handle
> + * @mem: memory entry to register
> + *
> + * This function removes specified memory entry in @rproc carveouts list.
> + */
> +void rproc_del_carveout(struct rproc *rproc, struct rproc_mem_entry *mem)
> +{
> +	struct rproc_mem_entry *entry, *tmp;
> +
> +	list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
> +		if (entry == mem) {
> +			list_del(&mem->node);
> +			return;
> +		}
> +	}
> +}
> +EXPORT_SYMBOL(rproc_del_carveout);

This API seems to me quite dangerous because it can be called while carveouts are in use.
At least some checks should be added...

What about using rproc_resource_cleanup instead?

Regards,
Arnaud

> +
> +/**
>   * rproc_mem_entry_init() - allocate and initialize rproc_mem_entry struct
>   * @dev: pointer on device struct
>   * @va: virtual address
> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> index 7c943f0a2fc4..43112aa78ffe 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -658,6 +658,7 @@ struct rproc *devm_rproc_alloc(struct device *dev, const char *name,
>  int devm_rproc_add(struct device *dev, struct rproc *rproc);
>  
>  void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem);
> +void rproc_del_carveout(struct rproc *rproc, struct rproc_mem_entry *mem);
>  
>  struct rproc_mem_entry *
>  rproc_mem_entry_init(struct device *dev,