From: Sinan Kaya <okaya@codeaurora.org> To: linux-scsi@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, jcm@redhat.com Cc: agross@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya <okaya@codeaurora.org>, Doug Gilbert <dgilbert@interlog.com>, "James E.J. Bottomley" <JBottomley@odin.com>, linux-kernel@vger.kernel.org Subject: [PATCH V2 2/3] scsi: fix compiler warning for sg Date: Sun, 8 Nov 2015 20:57:45 -0500 [thread overview] Message-ID: <1447034266-28003-3-git-send-email-okaya@codeaurora.org> (raw) In-Reply-To: <1447034266-28003-1-git-send-email-okaya@codeaurora.org> The MULDIV macro has been designed for small numbers. Compiler emits an overflow warning on 64 bit systems. This patch uses 64 bit numbers in order to suppress warning. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> --- drivers/scsi/sg.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 9d7b7db..112d8974 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -51,6 +51,7 @@ static int sg_version_num = 30536; /* 2 digits for each component */ #include <linux/atomic.h> #include <linux/ratelimit.h> #include <linux/uio.h> +#include <asm/div64.h> #include "scsi.h" #include <scsi/scsi_dbg.h> @@ -85,12 +86,17 @@ static void sg_proc_cleanup(void); * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m * calculates the same, but prevents the overflow when both m and d * are "small" numbers (like HZ and USER_HZ). - * Of course an overflow is inavoidable if the result of muldiv doesn't fit - * in 32 bits. */ -#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL)) +static inline u64 mult_frac64(u64 x, u32 numer, u32 denom) +{ + u64 r1 = do_div(x, denom); + u64 r2 = r1 * numer; + + do_div(r2, denom); + return (x * numer) + r2; +} -#define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) +#define SG_DEFAULT_TIMEOUT mult_frac64(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) int sg_big_buff = SG_DEF_RESERVED_SIZE; /* N.B. This variable is readable and writeable via @@ -877,10 +883,10 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) return result; if (val < 0) return -EIO; - if (val >= MULDIV (INT_MAX, USER_HZ, HZ)) - val = MULDIV (INT_MAX, USER_HZ, HZ); + if (val >= mult_frac64(INT_MAX, USER_HZ, HZ)) + val = mult_frac64(INT_MAX, USER_HZ, HZ); sfp->timeout_user = val; - sfp->timeout = MULDIV (val, HZ, USER_HZ); + sfp->timeout = mult_frac64(val, HZ, USER_HZ); return 0; case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ -- Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
WARNING: multiple messages have this Message-ID (diff)
From: okaya@codeaurora.org (Sinan Kaya) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 2/3] scsi: fix compiler warning for sg Date: Sun, 8 Nov 2015 20:57:45 -0500 [thread overview] Message-ID: <1447034266-28003-3-git-send-email-okaya@codeaurora.org> (raw) In-Reply-To: <1447034266-28003-1-git-send-email-okaya@codeaurora.org> The MULDIV macro has been designed for small numbers. Compiler emits an overflow warning on 64 bit systems. This patch uses 64 bit numbers in order to suppress warning. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> --- drivers/scsi/sg.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 9d7b7db..112d8974 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -51,6 +51,7 @@ static int sg_version_num = 30536; /* 2 digits for each component */ #include <linux/atomic.h> #include <linux/ratelimit.h> #include <linux/uio.h> +#include <asm/div64.h> #include "scsi.h" #include <scsi/scsi_dbg.h> @@ -85,12 +86,17 @@ static void sg_proc_cleanup(void); * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m * calculates the same, but prevents the overflow when both m and d * are "small" numbers (like HZ and USER_HZ). - * Of course an overflow is inavoidable if the result of muldiv doesn't fit - * in 32 bits. */ -#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL)) +static inline u64 mult_frac64(u64 x, u32 numer, u32 denom) +{ + u64 r1 = do_div(x, denom); + u64 r2 = r1 * numer; + + do_div(r2, denom); + return (x * numer) + r2; +} -#define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) +#define SG_DEFAULT_TIMEOUT mult_frac64(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) int sg_big_buff = SG_DEF_RESERVED_SIZE; /* N.B. This variable is readable and writeable via @@ -877,10 +883,10 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) return result; if (val < 0) return -EIO; - if (val >= MULDIV (INT_MAX, USER_HZ, HZ)) - val = MULDIV (INT_MAX, USER_HZ, HZ); + if (val >= mult_frac64(INT_MAX, USER_HZ, HZ)) + val = mult_frac64(INT_MAX, USER_HZ, HZ); sfp->timeout_user = val; - sfp->timeout = MULDIV (val, HZ, USER_HZ); + sfp->timeout = mult_frac64(val, HZ, USER_HZ); return 0; case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ -- Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
next prev parent reply other threads:[~2015-11-09 1:57 UTC|newest] Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-11-09 1:57 [PATCH V2 0/3] scsi: mptxsas: updates for ARM64 Sinan Kaya 2015-11-09 1:57 ` Sinan Kaya 2015-11-09 1:57 ` [PATCH V2 1/3] scsi: mptxsas: try 64 bit DMA when 32 bit DMA fails Sinan Kaya 2015-11-09 1:57 ` Sinan Kaya 2015-11-09 7:09 ` Hannes Reinecke 2015-11-09 7:09 ` Hannes Reinecke 2015-11-09 8:59 ` Arnd Bergmann 2015-11-09 8:59 ` Arnd Bergmann 2015-11-09 14:07 ` Sinan Kaya 2015-11-09 14:07 ` Sinan Kaya 2015-11-09 14:33 ` Arnd Bergmann 2015-11-09 14:33 ` Arnd Bergmann 2015-11-09 23:22 ` Sinan Kaya 2015-11-09 23:22 ` Sinan Kaya 2015-11-09 23:29 ` Timur Tabi 2015-11-09 23:29 ` Timur Tabi 2015-11-10 8:38 ` Arnd Bergmann 2015-11-10 8:38 ` Arnd Bergmann 2015-11-10 16:06 ` Sinan Kaya 2015-11-10 16:06 ` Sinan Kaya 2015-11-10 16:47 ` Arnd Bergmann 2015-11-10 16:47 ` Arnd Bergmann 2015-11-10 17:00 ` Timur Tabi 2015-11-10 17:00 ` Timur Tabi 2015-11-10 19:13 ` Arnd Bergmann 2015-11-10 19:13 ` Arnd Bergmann 2015-11-10 21:03 ` Timur Tabi 2015-11-10 21:03 ` Timur Tabi 2015-11-10 21:54 ` Arnd Bergmann 2015-11-10 21:54 ` Arnd Bergmann 2015-11-10 21:59 ` Timur Tabi 2015-11-10 21:59 ` Timur Tabi 2015-11-10 22:08 ` Arnd Bergmann 2015-11-10 22:08 ` Arnd Bergmann 2015-11-10 17:19 ` Sinan Kaya 2015-11-10 17:19 ` Sinan Kaya 2015-11-10 18:27 ` James Bottomley 2015-11-10 18:27 ` James Bottomley 2015-11-10 19:14 ` Sinan Kaya 2015-11-10 19:14 ` Sinan Kaya 2015-11-10 19:43 ` James Bottomley 2015-11-10 19:43 ` James Bottomley 2015-11-10 19:56 ` Sinan Kaya 2015-11-10 19:56 ` Sinan Kaya 2015-11-10 20:05 ` James Bottomley 2015-11-10 20:05 ` James Bottomley 2015-11-10 20:26 ` Sinan Kaya 2015-11-10 20:26 ` Sinan Kaya 2015-11-10 20:35 ` James Bottomley 2015-11-10 20:35 ` James Bottomley 2015-11-10 19:56 ` Arnd Bergmann 2015-11-10 19:56 ` Arnd Bergmann 2015-11-10 20:58 ` Sinan Kaya 2015-11-10 20:58 ` Sinan Kaya 2015-11-10 22:06 ` Arnd Bergmann 2015-11-10 22:06 ` Arnd Bergmann 2015-11-09 14:00 ` Sinan Kaya 2015-11-09 14:00 ` Sinan Kaya 2015-11-09 1:57 ` Sinan Kaya [this message] 2015-11-09 1:57 ` [PATCH V2 2/3] scsi: fix compiler warning for sg Sinan Kaya 2015-11-09 14:14 ` Andy Shevchenko 2015-11-09 14:14 ` Andy Shevchenko 2015-11-10 3:21 ` Sinan Kaya 2015-11-10 3:21 ` Sinan Kaya 2015-11-10 3:21 ` Sinan Kaya 2015-11-10 3:26 ` Timur Tabi 2015-11-10 3:26 ` Timur Tabi 2015-11-10 4:51 ` Sinan Kaya 2015-11-10 4:51 ` Sinan Kaya 2015-11-10 4:53 ` Timur Tabi 2015-11-10 4:53 ` Timur Tabi 2015-11-10 9:23 ` Andy Shevchenko 2015-11-10 9:23 ` Andy Shevchenko 2015-11-10 10:09 ` Arnd Bergmann 2015-11-10 10:09 ` Arnd Bergmann 2015-11-09 1:57 ` [PATCH V2 3/3] scsi: mptxsas: offload IRQ execution Sinan Kaya 2015-11-09 1:57 ` Sinan Kaya 2015-11-09 7:15 ` Hannes Reinecke 2015-11-09 7:15 ` Hannes Reinecke 2015-11-09 14:01 ` Sinan Kaya 2015-11-09 14:01 ` Sinan Kaya 2015-11-10 5:59 ` Sinan Kaya 2015-11-10 5:59 ` Sinan Kaya 2015-11-10 5:59 ` Sinan Kaya 2016-03-16 15:31 ` Christopher Covington 2016-03-16 15:31 ` Christopher Covington
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1447034266-28003-3-git-send-email-okaya@codeaurora.org \ --to=okaya@codeaurora.org \ --cc=JBottomley@odin.com \ --cc=agross@codeaurora.org \ --cc=cov@codeaurora.org \ --cc=dgilbert@interlog.com \ --cc=jcm@redhat.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-arm-msm@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-scsi@vger.kernel.org \ --cc=timur@codeaurora.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.