drivers/atm: Use DIV_ROUND_UP

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

In the case of the file drivers/atm/eni.c, I am a little bit suspicious of
the -1 at the end of the affected expression.  Please check that that is
what is wanted.

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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/atm/eni.c b/drivers/atm/eni.c
index 41b2204..5503bfc 100644 (file)
--- a/drivers/atm/eni.c
+++ b/drivers/atm/eni.c
@@ -1270,7 +1270,7 @@ static int comp_tx(struct eni_dev *eni_dev,int *pcr,int reserved,int *pre,
                        if (*pre < 3) (*pre)++; /* else fail later */
                        div = pre_div[*pre]*-*pcr;
                        DPRINTK("max div %d\n",div);
-                       *res = (TS_CLOCK+div-1)/div-1;
+                       *res = DIV_ROUND_UP(TS_CLOCK, div)-1;
                }
                if (*res < 0) *res = 0;
                if (*res > MID_SEG_MAX_RATE) *res = MID_SEG_MAX_RATE;

diff --git a/drivers/atm/horizon.c b/drivers/atm/horizon.c
index c0ac728..6154123 100644 (file)
--- a/drivers/atm/horizon.c
+++ b/drivers/atm/horizon.c
@@ -635,7 +635,7 @@ static int make_rate (const hrz_dev * dev, u32 c, rounding r,
                // take care of rounding
                switch (r) {
                        case round_down:
-                               pre = (br+(c<<div)-1)/(c<<div);
+                               pre = DIV_ROUND_UP(br, c<<div);
                                // but p must be non-zero
                                if (!pre)
                                        pre = 1;
@@ -668,7 +668,7 @@ static int make_rate (const hrz_dev * dev, u32 c, rounding r,
                        // take care of rounding
                        switch (r) {
                                case round_down:
-                                       pre = (br+(c<<div)-1)/(c<<div);
+                                       pre = DIV_ROUND_UP(br, c<<div);
                                        break;
                                case round_nearest:
                                        pre = (br+(c<<div)/2)/(c<<div);
@@ -698,7 +698,7 @@ got_it:
                if (bits)
                        *bits = (div<<CLOCK_SELECT_SHIFT) | (pre-1);
                if (actual) {
-                       *actual = (br + (pre<<div) - 1) / (pre<<div);
+                       *actual = DIV_ROUND_UP(br, pre<<div);
                        PRINTD (DBG_QOS, "actual rate: %u", *actual);
                }
                return 0;
@@ -1967,7 +1967,7 @@ static int __devinit hrz_init (hrz_dev * dev) {
   // Set the max AAL5 cell count to be just enough to contain the
   // largest AAL5 frame that the user wants to receive
   wr_regw (dev, MAX_AAL5_CELL_COUNT_OFF,
-          (max_rx_size + ATM_AAL5_TRAILER + ATM_CELL_PAYLOAD - 1) / ATM_CELL_PAYLOAD);
+          DIV_ROUND_UP(max_rx_size + ATM_AAL5_TRAILER, ATM_CELL_PAYLOAD));
   
   // Enable receive
   wr_regw (dev, RX_CONFIG_OFF, rd_regw (dev, RX_CONFIG_OFF) | RX_ENABLE);

diff --git a/drivers/atm/zatm.c b/drivers/atm/zatm.c
index 58583c6..752b1ba 100644 (file)
--- a/drivers/atm/zatm.c
+++ b/drivers/atm/zatm.c
@@ -496,8 +496,8 @@ static int open_rx_first(struct atm_vcc *vcc)
                        vcc->qos.rxtp.max_sdu = 65464;
                        /* fix this - we may want to receive 64kB SDUs
                           later */
-               cells = (vcc->qos.rxtp.max_sdu+ATM_AAL5_TRAILER+
-                   ATM_CELL_PAYLOAD-1)/ATM_CELL_PAYLOAD;
+               cells = DIV_ROUND_UP(vcc->qos.rxtp.max_sdu + ATM_AAL5_TRAILER,
+                               ATM_CELL_PAYLOAD);
                zatm_vcc->pool = pool_index(cells*ATM_CELL_PAYLOAD);
        }
        else {
@@ -820,7 +820,7 @@ static int alloc_shaper(struct atm_dev *dev,int *pcr,int min,int max,int ubr)
                        }
                        else {
                                i = 255;
-                               m = (ATM_OC3_PCR*255+max-1)/max;
+                               m = DIV_ROUND_UP(ATM_OC3_PCR*255, max);
                        }
                }
                if (i > m) {