Re: [PATCH v6 1/3] mtd: nand: raw: qcom_nandc: reorder qcom_nand_host struct

From: Manivannan Sadhasivam <mani@kernel.org>
To: Ansuel Smith <ansuelsmth@gmail.com>
Cc: Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	linux-mtd@lists.infradead.org, linux-arm-msm@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 1/3] mtd: nand: raw: qcom_nandc: reorder qcom_nand_host struct
Date: Wed, 15 Jun 2022 02:25:50 +0530	[thread overview]
Message-ID: <20220614205550.GA5596@thinkpad> (raw)
In-Reply-To: <62a2298c.1c69fb81.bc909.d2d0@mx.google.com>

On Thu, Jun 09, 2022 at 07:10:33PM +0200, Ansuel Smith wrote:
> On Thu, Jun 09, 2022 at 10:37:22PM +0530, Manivannan Sadhasivam wrote:
> > On Thu, Jun 09, 2022 at 03:23:42PM +0200, Ansuel Smith wrote:
> > > Reorder qcom_nand_host to save holes in the struct.
> > 
> > You forgot to reorder other structs also as I requested :/
> > 
> > Thanks,
> > Mani
> >
> 
> Mhhh I didn't find obvius hole in other struct.
> Think I will pass this with dwarf to better check them. Sorry!
> Feel free to point them if you notice obvius hole that I didn't notice.
> 

Sorry, I should be explicit. Please rearrange the members in other structs such
that we could avoid holes (in future also). For instance, in
"struct bam_transaction" u32's and bool are mixed in the middle. You could
organize them like,

struct pointer
struct
u32
bool

And this goes same for all other structs as well.

Thanks,
Mani

> > > 
> > > Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> > > ---
> > >  drivers/mtd/nand/raw/qcom_nandc.c | 10 ++++++----
> > >  1 file changed, 6 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> > > index 1a77542c6d67..7fbbd3e7784c 100644
> > > --- a/drivers/mtd/nand/raw/qcom_nandc.c
> > > +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> > > @@ -431,11 +431,12 @@ struct qcom_nand_controller {
> > >   *				and reserved bytes
> > >   * @cw_data:			the number of bytes within a codeword protected
> > >   *				by ECC
> > > + * @ecc_bytes_hw:		ECC bytes used by controller hardware for this
> > > + *				chip
> > > + *
> > >   * @use_ecc:			request the controller to use ECC for the
> > >   *				upcoming read/write
> > >   * @bch_enabled:		flag to tell whether BCH ECC mode is used
> > > - * @ecc_bytes_hw:		ECC bytes used by controller hardware for this
> > > - *				chip
> > >   * @status:			value to be returned if NAND_CMD_STATUS command
> > >   *				is executed
> > >   * @last_command:		keeps track of last command on this chip. used
> > > @@ -452,11 +453,12 @@ struct qcom_nand_host {
> > >  	int cs;
> > >  	int cw_size;
> > >  	int cw_data;
> > > -	bool use_ecc;
> > > -	bool bch_enabled;
> > >  	int ecc_bytes_hw;
> > >  	int spare_bytes;
> > >  	int bbm_size;
> > > +
> > > +	bool use_ecc;
> > > +	bool bch_enabled;
> > >  	u8 status;
> > >  	int last_command;
> > >  
> > > -- 
> > > 2.36.1
> > > 
> > 
> > -- 
> > மணிவண்ணன் சதாசிவம்
> 
> -- 
> 	Ansuel

-- 
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