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drivers/block: Use DIV_ROUND_UP
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The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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Julia Lawall authored and Jens Axboe committed Oct 9, 2008
1 parent 905bd78 commit 061837b
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Showing 3 changed files with 9 additions and 9 deletions.
8 changes: 4 additions & 4 deletions drivers/block/cciss.c
Original file line number Diff line number Diff line change
Expand Up @@ -3460,8 +3460,8 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
hba[i]->intr[SIMPLE_MODE_INT], dac ? "" : " not");

hba[i]->cmd_pool_bits =
kmalloc(((hba[i]->nr_cmds + BITS_PER_LONG -
1) / BITS_PER_LONG) * sizeof(unsigned long), GFP_KERNEL);
kmalloc(DIV_ROUND_UP(hba[i]->nr_cmds, BITS_PER_LONG)
* sizeof(unsigned long), GFP_KERNEL);
hba[i]->cmd_pool = (CommandList_struct *)
pci_alloc_consistent(hba[i]->pdev,
hba[i]->nr_cmds * sizeof(CommandList_struct),
Expand Down Expand Up @@ -3493,8 +3493,8 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
/* command and error info recs zeroed out before
they are used */
memset(hba[i]->cmd_pool_bits, 0,
((hba[i]->nr_cmds + BITS_PER_LONG -
1) / BITS_PER_LONG) * sizeof(unsigned long));
DIV_ROUND_UP(hba[i]->nr_cmds, BITS_PER_LONG)
* sizeof(unsigned long));

hba[i]->num_luns = 0;
hba[i]->highest_lun = -1;
Expand Down
2 changes: 1 addition & 1 deletion drivers/block/cpqarray.c
Original file line number Diff line number Diff line change
Expand Up @@ -424,7 +424,7 @@ static int __init cpqarray_register_ctlr( int i, struct pci_dev *pdev)
hba[i]->pci_dev, NR_CMDS * sizeof(cmdlist_t),
&(hba[i]->cmd_pool_dhandle));
hba[i]->cmd_pool_bits = kcalloc(
(NR_CMDS+BITS_PER_LONG-1)/BITS_PER_LONG, sizeof(unsigned long),
DIV_ROUND_UP(NR_CMDS, BITS_PER_LONG), sizeof(unsigned long),
GFP_KERNEL);

if (!hba[i]->cmd_pool_bits || !hba[i]->cmd_pool)
Expand Down
8 changes: 4 additions & 4 deletions drivers/block/floppy.c
Original file line number Diff line number Diff line change
Expand Up @@ -1355,20 +1355,20 @@ static void fdc_specify(void)
}

/* Convert step rate from microseconds to milliseconds and 4 bits */
srt = 16 - (DP->srt * scale_dtr / 1000 + NOMINAL_DTR - 1) / NOMINAL_DTR;
srt = 16 - DIV_ROUND_UP(DP->srt * scale_dtr / 1000, NOMINAL_DTR);
if (slow_floppy) {
srt = srt / 4;
}
SUPBOUND(srt, 0xf);
INFBOUND(srt, 0);

hlt = (DP->hlt * scale_dtr / 2 + NOMINAL_DTR - 1) / NOMINAL_DTR;
hlt = DIV_ROUND_UP(DP->hlt * scale_dtr / 2, NOMINAL_DTR);
if (hlt < 0x01)
hlt = 0x01;
else if (hlt > 0x7f)
hlt = hlt_max_code;

hut = (DP->hut * scale_dtr / 16 + NOMINAL_DTR - 1) / NOMINAL_DTR;
hut = DIV_ROUND_UP(DP->hut * scale_dtr / 16, NOMINAL_DTR);
if (hut < 0x1)
hut = 0x1;
else if (hut > 0xf)
Expand Down Expand Up @@ -2385,7 +2385,7 @@ static void rw_interrupt(void)

#ifdef FLOPPY_SANITY_CHECK
if (nr_sectors / ssize >
(in_sector_offset + current_count_sectors + ssize - 1) / ssize) {
DIV_ROUND_UP(in_sector_offset + current_count_sectors, ssize)) {
DPRINT("long rw: %x instead of %lx\n",
nr_sectors, current_count_sectors);
printk("rs=%d s=%d\n", R_SECTOR, SECTOR);
Expand Down

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