On 2022/05/08 22:41, Sergey Shtylyov wrote:
> The packed transfer mode masks are declared as *unsigned long* (which is
> a 64-bit type on 64-bit architectures), however the actual mask occupies
> only 20 bits (7 PIO modes, 5 MWDMA modes, and 8 UDMA modes), so we can
> safely use 32-bit *unsigned int* variables instead. Convert all libata
> functions taking as a parameter or returning a packed transfer mode mask.
> This saves 470 bytes of object code in libata-core.o alone...
>
> Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
> ---
> drivers/ata/libata-acpi.c | 9 +++++----
> drivers/ata/libata-core.c | 28 ++++++++++++-------------
> drivers/ata/pata_acpi.c | 2 +-
> drivers/ata/pata_ali.c | 2 +-
> drivers/ata/pata_amd.c | 14 ++++++-------
> drivers/ata/pata_hpt366.c | 2 +-
> drivers/ata/pata_hpt37x.c | 6 +++---
> drivers/ata/pata_hpt3x2n.c | 2 +-
> drivers/ata/pata_pdc2027x.c | 4 ++--
> drivers/ata/pata_serverworks.c | 4 ++--
> drivers/ata/pata_sis.c | 2 +-
> drivers/ata/pata_via.c | 2 +-
> include/linux/libata.h | 37 +++++++++++++++++-----------------
> 13 files changed, 57 insertions(+), 57 deletions(-)
>
> diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
> index 3d345d173556..cdb7c0238a43 100644
> --- a/drivers/ata/libata-acpi.c
> +++ b/drivers/ata/libata-acpi.c
> @@ -480,10 +480,10 @@ static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
> * RETURNS:
> * Determined xfermask.
> */
> -unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
> - const struct ata_acpi_gtm *gtm)
> +unsigned int ata_acpi_gtm_xfermask(struct ata_device *dev,
> + const struct ata_acpi_gtm *gtm)
> {
> - unsigned long xfer_mask = 0;
> + unsigned int xfer_mask = 0;
> unsigned int type;
> int unit;
> u8 mode;
> @@ -525,7 +525,8 @@ int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
> struct ata_device *dev;
>
> ata_for_each_dev(dev, &ap->link, ENABLED) {
> - unsigned long xfer_mask, udma_mask;
> + unsigned long udma_mask;
Why not change this one to unsigned int too ?
See below.
> + unsigned int xfer_mask;
>
> xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
> ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 95bd028aea4f..2a6f301c3359 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -93,7 +93,7 @@ struct ata_force_param {
> const char *name;
> u8 cbl;
> u8 spd_limit;
> - unsigned long xfer_mask;
> + unsigned int xfer_mask;
> unsigned int horkage_on;
> unsigned int horkage_off;
> u16 lflags;
> @@ -796,9 +796,9 @@ int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
> * RETURNS:
> * Packed xfer_mask.
> */
> -unsigned long ata_pack_xfermask(unsigned long pio_mask,
> - unsigned long mwdma_mask,
> - unsigned long udma_mask)
> +unsigned int ata_pack_xfermask(unsigned long pio_mask,
> + unsigned long mwdma_mask,
> + unsigned long udma_mask)
> {
> return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
> ((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
> @@ -816,7 +816,7 @@ EXPORT_SYMBOL_GPL(ata_pack_xfermask);
> * Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
> * Any NULL destination masks will be ignored.
> */
> -void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
> +void ata_unpack_xfermask(unsigned int xfer_mask, unsigned long *pio_mask,
> unsigned long *mwdma_mask, unsigned long *udma_mask)
> {
> if (pio_mask)
> @@ -850,7 +850,7 @@ static const struct ata_xfer_ent {
> * RETURNS:
> * Matching XFER_* value, 0xff if no match found.
> */
> -u8 ata_xfer_mask2mode(unsigned long xfer_mask)
> +u8 ata_xfer_mask2mode(unsigned int xfer_mask)
> {
> int highbit = fls(xfer_mask) - 1;
> const struct ata_xfer_ent *ent;
> @@ -874,7 +874,7 @@ EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
> * RETURNS:
> * Matching xfer_mask, 0 if no match found.
> */
> -unsigned long ata_xfer_mode2mask(u8 xfer_mode)
> +unsigned int ata_xfer_mode2mask(u8 xfer_mode)
> {
> const struct ata_xfer_ent *ent;
>
> @@ -923,7 +923,7 @@ EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
> * Constant C string representing highest speed listed in
> * @mode_mask, or the constant C string "<n/a>".
> */
> -const char *ata_mode_string(unsigned long xfer_mask)
> +const char *ata_mode_string(unsigned int xfer_mask)
> {
> static const char * const xfer_mode_str[] = {
> "PIO0",
> @@ -1376,7 +1376,7 @@ static inline void ata_dump_id(struct ata_device *dev, const u16 *id)
> * RETURNS:
> * Computed xfermask
> */
> -unsigned long ata_id_xfermask(const u16 *id)
> +unsigned int ata_id_xfermask(const u16 *id)
> {
> unsigned long pio_mask, mwdma_mask, udma_mask;
>
> @@ -2522,7 +2522,7 @@ int ata_dev_configure(struct ata_device *dev)
> struct ata_port *ap = dev->link->ap;
> bool print_info = ata_dev_print_info(dev);
> const u16 *id = dev->id;
> - unsigned long xfer_mask;
> + unsigned int xfer_mask;
> unsigned int err_mask;
> char revbuf[7]; /* XYZ-99\0 */
> char fwrevbuf[ATA_ID_FW_REV_LEN+1];
> @@ -3190,7 +3190,7 @@ u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
> int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
> {
> char buf[32];
> - unsigned long orig_mask, xfer_mask;
> + unsigned int orig_mask, xfer_mask;
> unsigned long pio_mask, mwdma_mask, udma_mask;
> int quiet, highbit;
>
> @@ -3369,7 +3369,7 @@ int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
>
> /* step 1: calculate xfer_mask */
> ata_for_each_dev(dev, link, ENABLED) {
> - unsigned long pio_mask, dma_mask;
> + unsigned int pio_mask, dma_mask;
> unsigned int mode_mask;
>
> mode_mask = ATA_DMA_MASK_ATA;
> @@ -4205,7 +4205,7 @@ static void ata_dev_xfermask(struct ata_device *dev)
> struct ata_link *link = dev->link;
> struct ata_port *ap = link->ap;
> struct ata_host *host = ap->host;
> - unsigned long xfer_mask;
> + unsigned int xfer_mask;
>
> /* controller modes available */
> xfer_mask = ata_pack_xfermask(ap->pio_mask,
> @@ -5764,7 +5764,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
> /* set cable, sata_spd_limit and report */
> for (i = 0; i < host->n_ports; i++) {
> struct ata_port *ap = host->ports[i];
> - unsigned long xfer_mask;
> + unsigned int xfer_mask;
>
> /* set SATA cable type if still unset */
> if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
> diff --git a/drivers/ata/pata_acpi.c b/drivers/ata/pata_acpi.c
> index ade4c3eee230..f8706ee427d2 100644
> --- a/drivers/ata/pata_acpi.c
> +++ b/drivers/ata/pata_acpi.c
> @@ -97,7 +97,7 @@ static unsigned long pacpi_discover_modes(struct ata_port *ap, struct ata_device
> * this case the list of discovered valid modes obtained by ACPI probing
> */
>
> -static unsigned long pacpi_mode_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int pacpi_mode_filter(struct ata_device *adev, unsigned int mask)
> {
> struct pata_acpi *acpi = adev->link->ap->private_data;
> return mask & acpi->mask[adev->devno];
> diff --git a/drivers/ata/pata_ali.c b/drivers/ata/pata_ali.c
> index 1b90cda27246..76ad0e73fe2a 100644
> --- a/drivers/ata/pata_ali.c
> +++ b/drivers/ata/pata_ali.c
> @@ -115,7 +115,7 @@ static int ali_c2_cable_detect(struct ata_port *ap)
> * fix that later on. Also ensure we do not do UDMA on WDC drives
> */
>
> -static unsigned long ali_20_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int ali_20_filter(struct ata_device *adev, unsigned int mask)
> {
> char model_num[ATA_ID_PROD_LEN + 1];
> /* No DMA on anything but a disk for now */
> diff --git a/drivers/ata/pata_amd.c b/drivers/ata/pata_amd.c
> index 154748cfcc79..f216f9d7b9ec 100644
> --- a/drivers/ata/pata_amd.c
> +++ b/drivers/ata/pata_amd.c
> @@ -264,8 +264,8 @@ static void amd133_set_dmamode(struct ata_port *ap, struct ata_device *adev)
> * cached during driver attach and are consulted to select transfer
> * mode.
> */
> -static unsigned long nv_mode_filter(struct ata_device *dev,
> - unsigned long xfer_mask)
> +static unsigned int nv_mode_filter(struct ata_device *dev,
> + unsigned int xfer_mask)
> {
> static const unsigned int udma_mask_map[] =
> { ATA_UDMA2, ATA_UDMA1, ATA_UDMA0, 0,
> @@ -274,7 +274,7 @@ static unsigned long nv_mode_filter(struct ata_device *dev,
> char acpi_str[32] = "";
> u32 saved_udma, udma;
> const struct ata_acpi_gtm *gtm;
> - unsigned long bios_limit = 0, acpi_limit = 0, limit;
> + unsigned int bios_limit = 0, acpi_limit = 0, limit;
>
> /* find out what BIOS configured */
> udma = saved_udma = (unsigned long)ap->host->private_data;
> @@ -310,10 +310,10 @@ static unsigned long nv_mode_filter(struct ata_device *dev,
> cable detection result */
> limit |= ata_pack_xfermask(ATA_PIO4, ATA_MWDMA2, ATA_UDMA2);
>
> - ata_port_dbg(ap, "nv_mode_filter: 0x%lx&0x%lx->0x%lx, "
> - "BIOS=0x%lx (0x%x) ACPI=0x%lx%s\n",
> - xfer_mask, limit, xfer_mask & limit, bios_limit,
> - saved_udma, acpi_limit, acpi_str);
> + ata_port_dbg(ap,
> + "nv_mode_filter: 0x%x&0x%x->0x%x, BIOS=0x%x (0x%x) ACPI=0x%x%s\n",
> + xfer_mask, limit, xfer_mask & limit, bios_limit,
> + saved_udma, acpi_limit, acpi_str);
>
> return xfer_mask & limit;
> }
> diff --git a/drivers/ata/pata_hpt366.c b/drivers/ata/pata_hpt366.c
> index c99e8f0708b3..7e441fb304d3 100644
> --- a/drivers/ata/pata_hpt366.c
> +++ b/drivers/ata/pata_hpt366.c
> @@ -194,7 +194,7 @@ static int hpt_dma_blacklisted(const struct ata_device *dev, char *modestr,
> * Block UDMA on devices that cause trouble with this controller.
> */
>
> -static unsigned long hpt366_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int hpt366_filter(struct ata_device *adev, unsigned int mask)
> {
> if (adev->class == ATA_DEV_ATA) {
> if (hpt_dma_blacklisted(adev, "UDMA", bad_ata33))
> diff --git a/drivers/ata/pata_hpt37x.c b/drivers/ata/pata_hpt37x.c
> index 156f304ef051..0e9f490214de 100644
> --- a/drivers/ata/pata_hpt37x.c
> +++ b/drivers/ata/pata_hpt37x.c
> @@ -278,7 +278,7 @@ static const char * const bad_ata100_5[] = {
> * Block UDMA on devices that cause trouble with this controller.
> */
>
> -static unsigned long hpt370_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int hpt370_filter(struct ata_device *adev, unsigned int mask)
> {
> if (adev->class == ATA_DEV_ATA) {
> if (hpt_dma_blacklisted(adev, "UDMA", bad_ata33))
> @@ -297,7 +297,7 @@ static unsigned long hpt370_filter(struct ata_device *adev, unsigned long mask)
> * Block UDMA on devices that cause trouble with this controller.
> */
>
> -static unsigned long hpt370a_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int hpt370a_filter(struct ata_device *adev, unsigned int mask)
> {
> if (adev->class == ATA_DEV_ATA) {
> if (hpt_dma_blacklisted(adev, "UDMA100", bad_ata100_5))
> @@ -314,7 +314,7 @@ static unsigned long hpt370a_filter(struct ata_device *adev, unsigned long mask)
> * The Marvell bridge chips used on the HighPoint SATA cards do not seem
> * to support the UltraDMA modes 1, 2, and 3 as well as any MWDMA modes...
> */
> -static unsigned long hpt372_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int hpt372_filter(struct ata_device *adev, unsigned int mask)
> {
> if (ata_id_is_sata(adev->id))
> mask &= ~((0xE << ATA_SHIFT_UDMA) | ATA_MASK_MWDMA);
> diff --git a/drivers/ata/pata_hpt3x2n.c b/drivers/ata/pata_hpt3x2n.c
> index 1f6afd8ee29b..071b2e4abf1d 100644
> --- a/drivers/ata/pata_hpt3x2n.c
> +++ b/drivers/ata/pata_hpt3x2n.c
> @@ -113,7 +113,7 @@ static u32 hpt3x2n_find_mode(struct ata_port *ap, int speed)
> * The Marvell bridge chips used on the HighPoint SATA cards do not seem
> * to support the UltraDMA modes 1, 2, and 3 as well as any MWDMA modes...
> */
> -static unsigned long hpt372n_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int hpt372n_filter(struct ata_device *adev, unsigned int mask)
> {
> if (ata_id_is_sata(adev->id))
> mask &= ~((0xE << ATA_SHIFT_UDMA) | ATA_MASK_MWDMA);
> diff --git a/drivers/ata/pata_pdc2027x.c b/drivers/ata/pata_pdc2027x.c
> index 4fbb3eed8b0b..4191aa61c8e4 100644
> --- a/drivers/ata/pata_pdc2027x.c
> +++ b/drivers/ata/pata_pdc2027x.c
> @@ -57,7 +57,7 @@ static int pdc2027x_prereset(struct ata_link *link, unsigned long deadline);
> static void pdc2027x_set_piomode(struct ata_port *ap, struct ata_device *adev);
> static void pdc2027x_set_dmamode(struct ata_port *ap, struct ata_device *adev);
> static int pdc2027x_check_atapi_dma(struct ata_queued_cmd *qc);
> -static unsigned long pdc2027x_mode_filter(struct ata_device *adev, unsigned long mask);
> +static unsigned int pdc2027x_mode_filter(struct ata_device *adev, unsigned int mask);
> static int pdc2027x_cable_detect(struct ata_port *ap);
> static int pdc2027x_set_mode(struct ata_link *link, struct ata_device **r_failed);
>
> @@ -251,7 +251,7 @@ static int pdc2027x_prereset(struct ata_link *link, unsigned long deadline)
> * Block UDMA on devices that cause trouble with this controller.
> */
>
> -static unsigned long pdc2027x_mode_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int pdc2027x_mode_filter(struct ata_device *adev, unsigned int mask)
> {
> unsigned char model_num[ATA_ID_PROD_LEN + 1];
> struct ata_device *pair = ata_dev_pair(adev);
> diff --git a/drivers/ata/pata_serverworks.c b/drivers/ata/pata_serverworks.c
> index e410fe44177f..c0bc4af0d196 100644
> --- a/drivers/ata/pata_serverworks.c
> +++ b/drivers/ata/pata_serverworks.c
> @@ -150,7 +150,7 @@ static u8 serverworks_is_csb(struct pci_dev *pdev)
> * bug we hit.
> */
>
> -static unsigned long serverworks_osb4_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int serverworks_osb4_filter(struct ata_device *adev, unsigned int mask)
> {
> if (adev->class == ATA_DEV_ATA)
> mask &= ~ATA_MASK_UDMA;
> @@ -166,7 +166,7 @@ static unsigned long serverworks_osb4_filter(struct ata_device *adev, unsigned l
> * Check the blacklist and disable UDMA5 if matched
> */
>
> -static unsigned long serverworks_csb_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int serverworks_csb_filter(struct ata_device *adev, unsigned int mask)
> {
> const char *p;
> char model_num[ATA_ID_PROD_LEN + 1];
> diff --git a/drivers/ata/pata_sis.c b/drivers/ata/pata_sis.c
> index b5b764e18adf..92e4cf05de2c 100644
> --- a/drivers/ata/pata_sis.c
> +++ b/drivers/ata/pata_sis.c
> @@ -525,7 +525,7 @@ static void sis_133_set_dmamode (struct ata_port *ap, struct ata_device *adev)
> * Block UDMA6 on devices that do not support it.
> */
>
> -static unsigned long sis_133_mode_filter(struct ata_device *adev, unsigned long mask)
> +static unsigned int sis_133_mode_filter(struct ata_device *adev, unsigned int mask)
> {
> struct ata_port *ap = adev->link->ap;
> struct pci_dev *pdev = to_pci_dev(ap->host->dev);
> diff --git a/drivers/ata/pata_via.c b/drivers/ata/pata_via.c
> index 215c02d4056a..34f00f389932 100644
> --- a/drivers/ata/pata_via.c
> +++ b/drivers/ata/pata_via.c
> @@ -352,7 +352,7 @@ static void via_set_dmamode(struct ata_port *ap, struct ata_device *adev)
> * one breed of Transcend SSD. Return the updated mask.
> */
>
> -static unsigned long via_mode_filter(struct ata_device *dev, unsigned long mask)
> +static unsigned int via_mode_filter(struct ata_device *dev, unsigned int mask)
> {
> struct ata_host *host = dev->link->ap->host;
> const struct via_isa_bridge *config = host->private_data;
> diff --git a/include/linux/libata.h b/include/linux/libata.h
> index 732de9014626..1429b7012ae8 100644
> --- a/include/linux/libata.h
> +++ b/include/linux/libata.h
> @@ -275,7 +275,7 @@ enum {
> PORT_DISABLED = 2,
>
> /* encoding various smaller bitmaps into a single
> - * unsigned long bitmap
> + * unsigned int bitmap
> */
> ATA_NR_PIO_MODES = 7,
> ATA_NR_MWDMA_MODES = 5,
> @@ -426,12 +426,9 @@ enum {
> };
>
> enum ata_xfer_mask {
> - ATA_MASK_PIO = ((1LU << ATA_NR_PIO_MODES) - 1)
> - << ATA_SHIFT_PIO,
> - ATA_MASK_MWDMA = ((1LU << ATA_NR_MWDMA_MODES) - 1)
> - << ATA_SHIFT_MWDMA,
> - ATA_MASK_UDMA = ((1LU << ATA_NR_UDMA_MODES) - 1)
> - << ATA_SHIFT_UDMA,
> + ATA_MASK_PIO = ((1U << ATA_NR_PIO_MODES) - 1) << ATA_SHIFT_PIO,
> + ATA_MASK_MWDMA = ((1U << ATA_NR_MWDMA_MODES) - 1) << ATA_SHIFT_MWDMA,
> + ATA_MASK_UDMA = ((1U << ATA_NR_UDMA_MODES) - 1) << ATA_SHIFT_UDMA,
> };
>
> enum hsm_task_states {
> @@ -886,7 +883,7 @@ struct ata_port_operations {
> * Configuration and exception handling
> */
> int (*cable_detect)(struct ata_port *ap);
> - unsigned long (*mode_filter)(struct ata_device *dev, unsigned long xfer_mask);
> + unsigned int (*mode_filter)(struct ata_device *dev, unsigned int xfer_mask);
> void (*set_piomode)(struct ata_port *ap, struct ata_device *dev);
> void (*set_dmamode)(struct ata_port *ap, struct ata_device *dev);
> int (*set_mode)(struct ata_link *link, struct ata_device **r_failed_dev);
> @@ -1103,16 +1100,18 @@ extern void ata_msleep(struct ata_port *ap, unsigned int msecs);
> extern u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask,
> u32 val, unsigned long interval, unsigned long timeout);
> extern int atapi_cmd_type(u8 opcode);
> -extern unsigned long ata_pack_xfermask(unsigned long pio_mask,
> - unsigned long mwdma_mask, unsigned long udma_mask);
> -extern void ata_unpack_xfermask(unsigned long xfer_mask,
> - unsigned long *pio_mask, unsigned long *mwdma_mask,
> - unsigned long *udma_mask);
> -extern u8 ata_xfer_mask2mode(unsigned long xfer_mask);
> -extern unsigned long ata_xfer_mode2mask(u8 xfer_mode);
> +extern unsigned int ata_pack_xfermask(unsigned long pio_mask,
> + unsigned long mwdma_mask,
> + unsigned long udma_mask);
> +extern void ata_unpack_xfermask(unsigned int xfer_mask,
> + unsigned long *pio_mask,
> + unsigned long *mwdma_mask,
> + unsigned long *udma_mask);
Why not change all of these to unsigned int too ?
They are defined as "1LU << shift" but everything actually fits within 32 bits
> +extern u8 ata_xfer_mask2mode(unsigned int xfer_mask);
> +extern unsigned int ata_xfer_mode2mask(u8 xfer_mode);
> extern int ata_xfer_mode2shift(u8 xfer_mode);
> -extern const char *ata_mode_string(unsigned long xfer_mask);
> -extern unsigned long ata_id_xfermask(const u16 *id);
> +extern const char *ata_mode_string(unsigned int xfer_mask);
> +extern unsigned int ata_id_xfermask(const u16 *id);
> extern int ata_std_qc_defer(struct ata_queued_cmd *qc);
> extern enum ata_completion_errors ata_noop_qc_prep(struct ata_queued_cmd *qc);
> extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
> @@ -1284,8 +1283,8 @@ static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap)
> }
> int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm);
> int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *stm);
> -unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
> - const struct ata_acpi_gtm *gtm);
> +unsigned int ata_acpi_gtm_xfermask(struct ata_device *dev,
> + const struct ata_acpi_gtm *gtm);
> int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm);
> #else
> static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap)
--
Damien Le Moal
Western Digital Research
