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hw/scsi/megasas: Silent GCC duplicated-cond warning

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GCC9 is confused when building with CFLAG -O3:

  hw/scsi/megasas.c: In function ‘megasas_scsi_realize’:
  hw/scsi/megasas.c:2387:26: error: duplicated ‘if’ condition [-Werror=duplicated-cond]
   2387 |     } else if (s->fw_sge >= 128 - MFI_PASS_FRAME_SIZE) {
  hw/scsi/megasas.c:2385:19: note: previously used here
   2385 |     if (s->fw_sge >= MEGASAS_MAX_SGE - MFI_PASS_FRAME_SIZE) {
  cc1: all warnings being treated as errors

When this device was introduced in commit e8f943c3bc, the author
cared about modularity, using a definition for the firmware limit.

However if the firmware limit isn't changed (MEGASAS_MAX_SGE = 128),
the code ends doing the same check twice.

Per the maintainer [*]:

> The original code assumed that one could change MFI_PASS_FRAME_SIZE,
> but it turned out not to be possible as it's being hardcoded in the
> drivers themselves (even though the interface provides mechanisms to
> query it). So we can remove the duplicate lines.

Add the 'MEGASAS_MIN_SGE' definition for the '64' magic value,
slightly rewrite the condition check to simplify a bit the logic
and remove the unnecessary / duplicated check.

[*] https://lore.kernel.org/qemu-devel/e0029fc5-882f-1d63-15e3-1c3dbe9b6a2c@suse.de/

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20230328210126.16282-1-philmd@linaro.org>
This commit is contained in:
Philippe Mathieu-Daudé 2019-12-17 18:34:00 +01:00 committed by Philippe Mathieu-Daudé
parent af33a321fa
commit 48143e0fd2
1 changed files with 10 additions and 6 deletions
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16
hw/scsi/megasas.c
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@ -42,6 +42,7 @@
#define MEGASAS_MAX_FRAMES 2048 /* Firmware limit at 65535 */
#define MEGASAS_DEFAULT_FRAMES 1000 /* Windows requires this */
#define MEGASAS_GEN2_DEFAULT_FRAMES 1008 /* Windows requires this */
#define MEGASAS_MIN_SGE 64
#define MEGASAS_MAX_SGE 128 /* Firmware limit */
#define MEGASAS_DEFAULT_SGE 80
#define MEGASAS_MAX_SECTORS 0xFFFF /* No real limit */
@ -2356,6 +2357,7 @@ static void megasas_scsi_realize(PCIDevice *dev, Error **errp)
MegasasState *s = MEGASAS(dev);
MegasasBaseClass *b = MEGASAS_GET_CLASS(s);
uint8_t *pci_conf;
uint32_t sge;
int i, bar_type;
Error *err = NULL;
int ret;
@ -2424,13 +2426,15 @@ static void megasas_scsi_realize(PCIDevice *dev, Error **errp)
if (!s->hba_serial) {
s->hba_serial = g_strdup(MEGASAS_HBA_SERIAL);
}
if (s->fw_sge >= MEGASAS_MAX_SGE - MFI_PASS_FRAME_SIZE) {
s->fw_sge = MEGASAS_MAX_SGE - MFI_PASS_FRAME_SIZE;
} else if (s->fw_sge >= 128 - MFI_PASS_FRAME_SIZE) {
s->fw_sge = 128 - MFI_PASS_FRAME_SIZE;
} else {
s->fw_sge = 64 - MFI_PASS_FRAME_SIZE;
sge = s->fw_sge + MFI_PASS_FRAME_SIZE;
if (sge < MEGASAS_MIN_SGE) {
sge = MEGASAS_MIN_SGE;
} else if (sge >= MEGASAS_MAX_SGE) {
sge = MEGASAS_MAX_SGE;
}
s->fw_sge = sge - MFI_PASS_FRAME_SIZE;
if (s->fw_cmds > MEGASAS_MAX_FRAMES) {
s->fw_cmds = MEGASAS_MAX_FRAMES;
}