Replace the hardcoded context ID mask (0xFF0) with GENMASK(11, 4) to
improve readability and follow kernel bitfield conventions. Use
FIELD_PREP and FIELD_GET instead of manual shifts for setting and
extracting ctxid values.
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
---
drivers/misc/fastrpc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index ce397c687161..0d8d89a2e220 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -37,7 +37,7 @@
#define FASTRPC_CTX_MAX (256)
#define FASTRPC_INIT_HANDLE 1
#define FASTRPC_DSP_UTILITIES_HANDLE 2
-#define FASTRPC_CTXID_MASK (0xFF0)
+#define FASTRPC_CTXID_MASK GENMASK(11, 4)
#define INIT_FILELEN_MAX (2 * 1024 * 1024)
#define INIT_FILE_NAMELEN_MAX (128)
#define FASTRPC_DEVICE_NAME "fastrpc"
@@ -515,7 +515,7 @@ static void fastrpc_context_free(struct kref *ref)
fastrpc_buf_free(ctx->buf);
spin_lock_irqsave(&cctx->lock, flags);
- idr_remove(&cctx->ctx_idr, ctx->ctxid >> 4);
+ idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
spin_unlock_irqrestore(&cctx->lock, flags);
kfree(ctx->maps);
@@ -651,7 +651,7 @@ static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
spin_unlock_irqrestore(&cctx->lock, flags);
goto err_idr;
}
- ctx->ctxid = ret << 4;
+ ctx->ctxid = FIELD_PREP(FASTRPC_CTXID_MASK, ret);
spin_unlock_irqrestore(&cctx->lock, flags);
kref_init(&ctx->refcount);
@@ -2506,7 +2506,7 @@ static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
if (len < sizeof(*rsp))
return -EINVAL;
- ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
+ ctxid = FIELD_GET(FASTRPC_CTXID_MASK, rsp->ctx);
spin_lock_irqsave(&cctx->lock, flags);
ctx = idr_find(&cctx->ctx_idr, ctxid);
--
2.34.1Hi Ekansh,
kernel test robot noticed the following build errors:
[auto build test ERROR on char-misc/char-misc-testing]
[also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.19 next-20260213]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Ekansh-Gupta/misc-fastrpc-Move-fdlist-to-invoke-context-structure/20260216-022305
base: char-misc/char-misc-testing
patch link: https://lore.kernel.org/r/20260215182136.3995111-3-ekansh.gupta%40oss.qualcomm.com
patch subject: [PATCH v6 2/4] misc: fastrpc: Replace hardcoded ctxid mask with GENMASK
config: sh-allyesconfig (https://download.01.org/0day-ci/archive/20260216/202602161130.5b7COBet-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260216/202602161130.5b7COBet-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202602161130.5b7COBet-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/misc/fastrpc.c: In function 'fastrpc_context_free':
>> drivers/misc/fastrpc.c:518:36: error: implicit declaration of function 'FIELD_GET' [-Wimplicit-function-declaration]
518 | idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
| ^~~~~~~~~
drivers/misc/fastrpc.c: In function 'fastrpc_context_alloc':
>> drivers/misc/fastrpc.c:654:22: error: implicit declaration of function 'FIELD_PREP' [-Wimplicit-function-declaration]
654 | ctx->ctxid = FIELD_PREP(FASTRPC_CTXID_MASK, ret);
| ^~~~~~~~~~
vim +/FIELD_GET +518 drivers/misc/fastrpc.c
500
501 static void fastrpc_context_free(struct kref *ref)
502 {
503 struct fastrpc_invoke_ctx *ctx;
504 struct fastrpc_channel_ctx *cctx;
505 unsigned long flags;
506 int i;
507
508 ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
509 cctx = ctx->cctx;
510
511 for (i = 0; i < ctx->nbufs; i++)
512 fastrpc_map_put(ctx->maps[i]);
513
514 if (ctx->buf)
515 fastrpc_buf_free(ctx->buf);
516
517 spin_lock_irqsave(&cctx->lock, flags);
> 518 idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
519 spin_unlock_irqrestore(&cctx->lock, flags);
520
521 kfree(ctx->maps);
522 kfree(ctx->olaps);
523 kfree(ctx);
524
525 fastrpc_channel_ctx_put(cctx);
526 }
527
528 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
529 {
530 kref_get(&ctx->refcount);
531 }
532
533 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
534 {
535 kref_put(&ctx->refcount, fastrpc_context_free);
536 }
537
538 static void fastrpc_context_put_wq(struct work_struct *work)
539 {
540 struct fastrpc_invoke_ctx *ctx =
541 container_of(work, struct fastrpc_invoke_ctx, put_work);
542
543 fastrpc_context_put(ctx);
544 }
545
546 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
547 static int olaps_cmp(const void *a, const void *b)
548 {
549 struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
550 struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
551 /* sort with lowest starting buffer first */
552 int st = CMP(pa->start, pb->start);
553 /* sort with highest ending buffer first */
554 int ed = CMP(pb->end, pa->end);
555
556 return st == 0 ? ed : st;
557 }
558
559 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
560 {
561 u64 max_end = 0;
562 int i;
563
564 for (i = 0; i < ctx->nbufs; ++i) {
565 ctx->olaps[i].start = ctx->args[i].ptr;
566 ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
567 ctx->olaps[i].raix = i;
568 }
569
570 sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
571
572 for (i = 0; i < ctx->nbufs; ++i) {
573 /* Falling inside previous range */
574 if (ctx->olaps[i].start < max_end) {
575 ctx->olaps[i].mstart = max_end;
576 ctx->olaps[i].mend = ctx->olaps[i].end;
577 ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
578
579 if (ctx->olaps[i].end > max_end) {
580 max_end = ctx->olaps[i].end;
581 } else {
582 ctx->olaps[i].mend = 0;
583 ctx->olaps[i].mstart = 0;
584 }
585
586 } else {
587 ctx->olaps[i].mend = ctx->olaps[i].end;
588 ctx->olaps[i].mstart = ctx->olaps[i].start;
589 ctx->olaps[i].offset = 0;
590 max_end = ctx->olaps[i].end;
591 }
592 }
593 }
594
595 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
596 struct fastrpc_user *user, u32 kernel, u32 sc,
597 struct fastrpc_invoke_args *args)
598 {
599 struct fastrpc_channel_ctx *cctx = user->cctx;
600 struct fastrpc_invoke_ctx *ctx = NULL;
601 unsigned long flags;
602 int ret;
603
604 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
605 if (!ctx)
606 return ERR_PTR(-ENOMEM);
607
608 INIT_LIST_HEAD(&ctx->node);
609 ctx->fl = user;
610 ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
611 ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
612 REMOTE_SCALARS_OUTBUFS(sc);
613
614 if (ctx->nscalars) {
615 ctx->maps = kcalloc(ctx->nscalars,
616 sizeof(*ctx->maps), GFP_KERNEL);
617 if (!ctx->maps) {
618 kfree(ctx);
619 return ERR_PTR(-ENOMEM);
620 }
621 ctx->olaps = kcalloc(ctx->nscalars,
622 sizeof(*ctx->olaps), GFP_KERNEL);
623 if (!ctx->olaps) {
624 kfree(ctx->maps);
625 kfree(ctx);
626 return ERR_PTR(-ENOMEM);
627 }
628 ctx->args = args;
629 fastrpc_get_buff_overlaps(ctx);
630 }
631
632 /* Released in fastrpc_context_put() */
633 fastrpc_channel_ctx_get(cctx);
634
635 ctx->sc = sc;
636 ctx->retval = -1;
637 ctx->pid = current->pid;
638 ctx->client_id = user->client_id;
639 ctx->cctx = cctx;
640 init_completion(&ctx->work);
641 INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
642
643 spin_lock(&user->lock);
644 list_add_tail(&ctx->node, &user->pending);
645 spin_unlock(&user->lock);
646
647 spin_lock_irqsave(&cctx->lock, flags);
648 ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
649 FASTRPC_CTX_MAX, GFP_ATOMIC);
650 if (ret < 0) {
651 spin_unlock_irqrestore(&cctx->lock, flags);
652 goto err_idr;
653 }
> 654 ctx->ctxid = FIELD_PREP(FASTRPC_CTXID_MASK, ret);
655 spin_unlock_irqrestore(&cctx->lock, flags);
656
657 kref_init(&ctx->refcount);
658
659 return ctx;
660 err_idr:
661 spin_lock(&user->lock);
662 list_del(&ctx->node);
663 spin_unlock(&user->lock);
664 fastrpc_channel_ctx_put(cctx);
665 kfree(ctx->maps);
666 kfree(ctx->olaps);
667 kfree(ctx);
668
669 return ERR_PTR(ret);
670 }
671
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Ekansh,
kernel test robot noticed the following build errors:
[auto build test ERROR on char-misc/char-misc-testing]
[also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.19 next-20260213]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Ekansh-Gupta/misc-fastrpc-Move-fdlist-to-invoke-context-structure/20260216-022305
base: char-misc/char-misc-testing
patch link: https://lore.kernel.org/r/20260215182136.3995111-3-ekansh.gupta%40oss.qualcomm.com
patch subject: [PATCH v6 2/4] misc: fastrpc: Replace hardcoded ctxid mask with GENMASK
config: hexagon-randconfig-001-20260216 (https://download.01.org/0day-ci/archive/20260216/202602161009.M2K52X34-lkp@intel.com/config)
compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project e86750b29fa0ff207cd43213d66dabe565417638)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260216/202602161009.M2K52X34-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202602161009.M2K52X34-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/misc/fastrpc.c:518:29: error: call to undeclared function 'FIELD_GET'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
518 | idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
| ^
>> drivers/misc/fastrpc.c:654:15: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
654 | ctx->ctxid = FIELD_PREP(FASTRPC_CTXID_MASK, ret);
| ^
drivers/misc/fastrpc.c:2509:10: error: call to undeclared function 'FIELD_GET'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
2509 | ctxid = FIELD_GET(FASTRPC_CTXID_MASK, rsp->ctx);
| ^
3 errors generated.
vim +/FIELD_GET +518 drivers/misc/fastrpc.c
500
501 static void fastrpc_context_free(struct kref *ref)
502 {
503 struct fastrpc_invoke_ctx *ctx;
504 struct fastrpc_channel_ctx *cctx;
505 unsigned long flags;
506 int i;
507
508 ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
509 cctx = ctx->cctx;
510
511 for (i = 0; i < ctx->nbufs; i++)
512 fastrpc_map_put(ctx->maps[i]);
513
514 if (ctx->buf)
515 fastrpc_buf_free(ctx->buf);
516
517 spin_lock_irqsave(&cctx->lock, flags);
> 518 idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
519 spin_unlock_irqrestore(&cctx->lock, flags);
520
521 kfree(ctx->maps);
522 kfree(ctx->olaps);
523 kfree(ctx);
524
525 fastrpc_channel_ctx_put(cctx);
526 }
527
528 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
529 {
530 kref_get(&ctx->refcount);
531 }
532
533 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
534 {
535 kref_put(&ctx->refcount, fastrpc_context_free);
536 }
537
538 static void fastrpc_context_put_wq(struct work_struct *work)
539 {
540 struct fastrpc_invoke_ctx *ctx =
541 container_of(work, struct fastrpc_invoke_ctx, put_work);
542
543 fastrpc_context_put(ctx);
544 }
545
546 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
547 static int olaps_cmp(const void *a, const void *b)
548 {
549 struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
550 struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
551 /* sort with lowest starting buffer first */
552 int st = CMP(pa->start, pb->start);
553 /* sort with highest ending buffer first */
554 int ed = CMP(pb->end, pa->end);
555
556 return st == 0 ? ed : st;
557 }
558
559 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
560 {
561 u64 max_end = 0;
562 int i;
563
564 for (i = 0; i < ctx->nbufs; ++i) {
565 ctx->olaps[i].start = ctx->args[i].ptr;
566 ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
567 ctx->olaps[i].raix = i;
568 }
569
570 sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
571
572 for (i = 0; i < ctx->nbufs; ++i) {
573 /* Falling inside previous range */
574 if (ctx->olaps[i].start < max_end) {
575 ctx->olaps[i].mstart = max_end;
576 ctx->olaps[i].mend = ctx->olaps[i].end;
577 ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
578
579 if (ctx->olaps[i].end > max_end) {
580 max_end = ctx->olaps[i].end;
581 } else {
582 ctx->olaps[i].mend = 0;
583 ctx->olaps[i].mstart = 0;
584 }
585
586 } else {
587 ctx->olaps[i].mend = ctx->olaps[i].end;
588 ctx->olaps[i].mstart = ctx->olaps[i].start;
589 ctx->olaps[i].offset = 0;
590 max_end = ctx->olaps[i].end;
591 }
592 }
593 }
594
595 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
596 struct fastrpc_user *user, u32 kernel, u32 sc,
597 struct fastrpc_invoke_args *args)
598 {
599 struct fastrpc_channel_ctx *cctx = user->cctx;
600 struct fastrpc_invoke_ctx *ctx = NULL;
601 unsigned long flags;
602 int ret;
603
604 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
605 if (!ctx)
606 return ERR_PTR(-ENOMEM);
607
608 INIT_LIST_HEAD(&ctx->node);
609 ctx->fl = user;
610 ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
611 ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
612 REMOTE_SCALARS_OUTBUFS(sc);
613
614 if (ctx->nscalars) {
615 ctx->maps = kcalloc(ctx->nscalars,
616 sizeof(*ctx->maps), GFP_KERNEL);
617 if (!ctx->maps) {
618 kfree(ctx);
619 return ERR_PTR(-ENOMEM);
620 }
621 ctx->olaps = kcalloc(ctx->nscalars,
622 sizeof(*ctx->olaps), GFP_KERNEL);
623 if (!ctx->olaps) {
624 kfree(ctx->maps);
625 kfree(ctx);
626 return ERR_PTR(-ENOMEM);
627 }
628 ctx->args = args;
629 fastrpc_get_buff_overlaps(ctx);
630 }
631
632 /* Released in fastrpc_context_put() */
633 fastrpc_channel_ctx_get(cctx);
634
635 ctx->sc = sc;
636 ctx->retval = -1;
637 ctx->pid = current->pid;
638 ctx->client_id = user->client_id;
639 ctx->cctx = cctx;
640 init_completion(&ctx->work);
641 INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
642
643 spin_lock(&user->lock);
644 list_add_tail(&ctx->node, &user->pending);
645 spin_unlock(&user->lock);
646
647 spin_lock_irqsave(&cctx->lock, flags);
648 ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
649 FASTRPC_CTX_MAX, GFP_ATOMIC);
650 if (ret < 0) {
651 spin_unlock_irqrestore(&cctx->lock, flags);
652 goto err_idr;
653 }
> 654 ctx->ctxid = FIELD_PREP(FASTRPC_CTXID_MASK, ret);
655 spin_unlock_irqrestore(&cctx->lock, flags);
656
657 kref_init(&ctx->refcount);
658
659 return ctx;
660 err_idr:
661 spin_lock(&user->lock);
662 list_del(&ctx->node);
663 spin_unlock(&user->lock);
664 fastrpc_channel_ctx_put(cctx);
665 kfree(ctx->maps);
666 kfree(ctx->olaps);
667 kfree(ctx);
668
669 return ERR_PTR(ret);
670 }
671
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On 2/16/26 3:39 AM, kernel test robot wrote: > Hi Ekansh, > > kernel test robot noticed the following build errors: > > [auto build test ERROR on char-misc/char-misc-testing] > [also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.19 next-20260213] > [If your patch is applied to the wrong git tree, kindly drop us a note. > And when submitting patch, we suggest to use '--base' as documented in > https://git-scm.com/docs/git-format-patch#_base_tree_information] > > url: https://github.com/intel-lab-lkp/linux/commits/Ekansh-Gupta/misc-fastrpc-Move-fdlist-to-invoke-context-structure/20260216-022305 > base: char-misc/char-misc-testing > patch link: https://lore.kernel.org/r/20260215182136.3995111-3-ekansh.gupta%40oss.qualcomm.com > patch subject: [PATCH v6 2/4] misc: fastrpc: Replace hardcoded ctxid mask with GENMASK > config: hexagon-randconfig-001-20260216 (https://download.01.org/0day-ci/archive/20260216/202602161009.M2K52X34-lkp@intel.com/config) > compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project e86750b29fa0ff207cd43213d66dabe565417638) > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260216/202602161009.M2K52X34-lkp@intel.com/reproduce) > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot <lkp@intel.com> > | Closes: https://lore.kernel.org/oe-kbuild-all/202602161009.M2K52X34-lkp@intel.com/ > > All errors (new ones prefixed by >>): > >>> drivers/misc/fastrpc.c:518:29: error: call to undeclared function 'FIELD_GET'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] > 518 | idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid)); #include <linux/bitops.h> Konrad
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