part/dev_desc: Add log2 of blocksize to block_dev_desc data struct

log2 of the device block size serves as the shift value used to calculate
the block number to read in file systems when implementing avaiable block
sizes.
It is needed quite often in file systems thus it is pre-calculated and
stored in the block device descriptor.

Signed-off-by: Egbert Eich <eich@suse.com>

9 files changed, 21 insertions, 0 deletions

diff --git a/common/cmd_ide.c b/common/cmd_ide.c
index 0105bdb..78b4aa7 100644
--- a/common/cmd_ide.c
+++ b/common/cmd_ide.c
@@ -455,6 +455,8 @@ void ide_init(void)
 		ide_dev_desc[i].dev = i;
 		ide_dev_desc[i].part_type = PART_TYPE_UNKNOWN;
 		ide_dev_desc[i].blksz = 0;
+		ide_dev_desc[i].log2blksz =
+			LOG2_INVALID(typeof(ide_dev_desc[i].log2blksz));
 		ide_dev_desc[i].lba = 0;
 		ide_dev_desc[i].block_read = ide_read;
 		ide_dev_desc[i].block_write = ide_write;
@@ -806,6 +808,7 @@ static void ide_ident(block_dev_desc_t *dev_desc)
 	/* assuming HD */
 	dev_desc->type = DEV_TYPE_HARDDISK;
 	dev_desc->blksz = ATA_BLOCKSIZE;
+	dev_desc->log2blksz = LOG2(dev_desc->blksz);
 	dev_desc->lun = 0;	/* just to fill something in... */
 
 #if 0				/* only used to test the powersaving mode,
@@ -1448,6 +1451,7 @@ static void atapi_inquiry(block_dev_desc_t *dev_desc)
 	dev_desc->lun = 0;
 	dev_desc->lba = 0;
 	dev_desc->blksz = 0;
+	dev_desc->log2blksz = LOG2_INVALID(typeof(dev_desc->log2blksz));
 	dev_desc->type = iobuf[0] & 0x1f;
 
 	if ((iobuf[1] & 0x80) == 0x80)
@@ -1492,6 +1496,7 @@ static void atapi_inquiry(block_dev_desc_t *dev_desc)
 	dev_desc->blksz = ((unsigned long) iobuf[4] << 24) +
 		((unsigned long) iobuf[5] << 16) +
 		((unsigned long) iobuf[6] << 8) + ((unsigned long) iobuf[7]);
+	dev_desc->log2blksz = LOG2(dev_desc->blksz);
 #ifdef CONFIG_LBA48
 	/* ATAPI devices cannot use 48bit addressing (ATA/ATAPI v7) */
 	dev_desc->lba48 = 0;
diff --git a/common/cmd_sata.c b/common/cmd_sata.c
index 8d57285..5a57a37 100644
--- a/common/cmd_sata.c
+++ b/common/cmd_sata.c
@@ -44,6 +44,7 @@ int __sata_initialize(void)
 		sata_dev_desc[i].type = DEV_TYPE_HARDDISK;
 		sata_dev_desc[i].lba = 0;
 		sata_dev_desc[i].blksz = 512;
+		sata_dev_desc[i].log2blksz = LOG2(sata_dev_desc[i].blksz);
 		sata_dev_desc[i].block_read = sata_read;
 		sata_dev_desc[i].block_write = sata_write;
 
diff --git a/common/cmd_scsi.c b/common/cmd_scsi.c
index 13b3d99..294d9f5 100644
--- a/common/cmd_scsi.c
+++ b/common/cmd_scsi.c
@@ -106,6 +106,8 @@ void scsi_scan(int mode)
 		scsi_dev_desc[i].lun=0xff;
 		scsi_dev_desc[i].lba=0;
 		scsi_dev_desc[i].blksz=0;
+		scsi_dev_desc[i].log2blksz =
+			LOG2_INVALID(typeof(scsi_dev_desc[i].log2blksz));
 		scsi_dev_desc[i].type=DEV_TYPE_UNKNOWN;
 		scsi_dev_desc[i].vendor[0]=0;
 		scsi_dev_desc[i].product[0]=0;
@@ -166,6 +168,8 @@ void scsi_scan(int mode)
 			}
 			scsi_dev_desc[scsi_max_devs].lba=capacity;
 			scsi_dev_desc[scsi_max_devs].blksz=blksz;
+			scsi_dev_desc[scsi_max_devs].log2blksz =
+				LOG2(scsi_dev_desc[scsi_max_devs].blksz);
 			scsi_dev_desc[scsi_max_devs].type=perq;
 			init_part(&scsi_dev_desc[scsi_max_devs]);
 removable:
diff --git a/common/usb_storage.c b/common/usb_storage.c
index fb322b4..c5db044 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -1430,6 +1430,7 @@ int usb_stor_get_info(struct usb_device *dev, struct us_data *ss,
 			*capacity, *blksz);
 	dev_desc->lba = *capacity;
 	dev_desc->blksz = *blksz;
+	dev_desc->log2blksz = LOG2(dev_desc->blksz);
 	dev_desc->type = perq;
 	USB_STOR_PRINTF(" address %d\n", dev_desc->target);
 	USB_STOR_PRINTF("partype: %d\n", dev_desc->part_type);
diff --git a/drivers/block/ata_piix.c b/drivers/block/ata_piix.c
index 1e33a66..fcae448 100644
--- a/drivers/block/ata_piix.c
+++ b/drivers/block/ata_piix.c
@@ -406,6 +406,7 @@ void sata_identify(int num, int dev)
 	/* assuming HD */
 	sata_dev_desc[devno].type = DEV_TYPE_HARDDISK;
 	sata_dev_desc[devno].blksz = ATA_BLOCKSIZE;
+	sata_dev_desc[devno].log2blksz = LOG2(sata_dev_desc[devno].blksz);
 	sata_dev_desc[devno].lun = 0;	/* just to fill something in... */
 }
 
diff --git a/drivers/block/pata_bfin.c b/drivers/block/pata_bfin.c
index b847dd9..27ecaf4 100644
--- a/drivers/block/pata_bfin.c
+++ b/drivers/block/pata_bfin.c
@@ -897,6 +897,8 @@ static void bfin_ata_identify(struct ata_port *ap, int dev)
 	/* assuming HD */
 	sata_dev_desc[ap->port_no].type = DEV_TYPE_HARDDISK;
 	sata_dev_desc[ap->port_no].blksz = ATA_SECT_SIZE;
+	sata_dev_desc[ap->port_no].log2blksz =
+		LOG2(sata_dev_desc[ap->port_no].blksz);
 	sata_dev_desc[ap->port_no].lun = 0;	/* just to fill something in... */
 
 	printf("PATA device#%d %s is found on ata port#%d.\n",
diff --git a/drivers/block/systemace.c b/drivers/block/systemace.c
index bf29cbb..b08715f 100644
--- a/drivers/block/systemace.c
+++ b/drivers/block/systemace.c
@@ -127,6 +127,7 @@ block_dev_desc_t *systemace_get_dev(int dev)
 		systemace_dev.part_type = PART_TYPE_UNKNOWN;
 		systemace_dev.type = DEV_TYPE_HARDDISK;
 		systemace_dev.blksz = 512;
+		systemace_dev.log2blksz = LOG2(systemace_dev.blksz);
 		systemace_dev.removable = 1;
 		systemace_dev.block_read = systemace_read;
 
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 23aeec1..2590f1b 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1203,6 +1203,7 @@ static int mmc_startup(struct mmc *mmc)
 	mmc->block_dev.lun = 0;
 	mmc->block_dev.type = 0;
 	mmc->block_dev.blksz = mmc->read_bl_len;
+	mmc->block_dev.log2blksz = LOG2(mmc->block_dev.blksz);
 	mmc->block_dev.lba = lldiv(mmc->capacity, mmc->read_bl_len);
 	sprintf(mmc->block_dev.vendor, "Man %06x Snr %04x%04x",
 		mmc->cid[0] >> 24, (mmc->cid[2] & 0xffff),
diff --git a/include/part.h b/include/part.h
index 12e9b05..f7c7cc5 100644
--- a/include/part.h
+++ b/include/part.h
@@ -38,6 +38,7 @@ typedef struct block_dev_desc {
 #endif
 	lbaint_t	lba;		/* number of blocks */
 	unsigned long	blksz;		/* block size */
+	int		log2blksz;	/* for convenience: log2(blksz) */
 	char		vendor [40+1];	/* IDE model, SCSI Vendor */
 	char		product[20+1];	/* IDE Serial no, SCSI product */
 	char		revision[8+1];	/* firmware revision */
@@ -58,6 +59,10 @@ typedef struct block_dev_desc {
 #define BLOCK_CNT(size, block_dev_desc) (PAD_COUNT(size, block_dev_desc->blksz))
 #define PAD_TO_BLOCKSIZE(size, block_dev_desc) \
 	(PAD_SIZE(size, block_dev_desc->blksz))
+#define LOG2(x) (((x & 0xaaaaaaaa) ? 1 : 0) + ((x & 0xcccccccc) ? 2 : 0) + \
+		 ((x & 0xf0f0f0f0) ? 4 : 0) + ((x & 0xff00ff00) ? 8 : 0) + \
+		 ((x & 0xffff0000) ? 16 : 0))
+#define LOG2_INVALID(type) ((type)((sizeof(type)<<3)-1))
 
 /* Interface types: */
 #define IF_TYPE_UNKNOWN		0