weiping zhang
2017-Dec-01 17:51 UTC
[PATCH] virtio_mmio: add cleanup for virtio_mmio_probe
cleanup all resource allocated by virtio_mmio_probe. Signed-off-by: weiping zhang <zhangweiping at didichuxing.com> --- drivers/virtio/virtio_mmio.c | 34 ++++++++++++++++++++++++++-------- 1 file changed, 26 insertions(+), 8 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 74dc717..3fd0e66 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -513,8 +513,10 @@ static int virtio_mmio_probe(struct platform_device *pdev) return -EBUSY; vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL); - if (!vm_dev) - return -ENOMEM; + if (!vm_dev) { + rc = -ENOMEM; + goto free_mem; + } vm_dev->vdev.dev.parent = &pdev->dev; vm_dev->vdev.dev.release = virtio_mmio_release_dev_empty; @@ -524,14 +526,17 @@ static int virtio_mmio_probe(struct platform_device *pdev) spin_lock_init(&vm_dev->lock); vm_dev->base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem)); - if (vm_dev->base == NULL) - return -EFAULT; + if (vm_dev->base == NULL) { + rc = -EFAULT; + goto free_vmdev; + } /* Check magic value */ magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE); if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) { dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic); - return -ENODEV; + rc = -ENODEV; + goto unmap; } /* Check device version */ @@ -539,7 +544,8 @@ static int virtio_mmio_probe(struct platform_device *pdev) if (vm_dev->version < 1 || vm_dev->version > 2) { dev_err(&pdev->dev, "Version %ld not supported!\n", vm_dev->version); - return -ENXIO; + rc = -ENXIO; + goto unmap; } vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID); @@ -548,7 +554,8 @@ static int virtio_mmio_probe(struct platform_device *pdev) * virtio-mmio device with an ID 0 is a (dummy) placeholder * with no function. End probing now with no error reported. */ - return -ENODEV; + rc = -ENODEV; + goto unmap; } vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID); @@ -573,7 +580,18 @@ static int virtio_mmio_probe(struct platform_device *pdev) platform_set_drvdata(pdev, vm_dev); - return register_virtio_device(&vm_dev->vdev); + rc = register_virtio_device(&vm_dev->vdev); + if (rc) + goto unmap; + return 0; +unmap: + iounmap(vm_dev->base); +free_mem: + devm_release_mem_region(&pdev->dev, mem->start, + resource_size(mem)); +free_vmdev: + devm_kfree(&pdev->dev, vm_dev); + return rc; } static int virtio_mmio_remove(struct platform_device *pdev) -- 2.9.4
Cornelia Huck
2017-Dec-04 10:24 UTC
[PATCH] virtio_mmio: add cleanup for virtio_mmio_probe
On Sat, 2 Dec 2017 01:51:40 +0800 weiping zhang <zwp10758 at gmail.com> wrote:> cleanup all resource allocated by virtio_mmio_probe. > > Signed-off-by: weiping zhang <zhangweiping at didichuxing.com> > --- > drivers/virtio/virtio_mmio.c | 34 ++++++++++++++++++++++++++-------- > 1 file changed, 26 insertions(+), 8 deletions(-) > > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c > index 74dc717..3fd0e66 100644 > --- a/drivers/virtio/virtio_mmio.c > +++ b/drivers/virtio/virtio_mmio.c > @@ -513,8 +513,10 @@ static int virtio_mmio_probe(struct platform_device *pdev) > return -EBUSY; > > vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL); > - if (!vm_dev) > - return -ENOMEM; > + if (!vm_dev) { > + rc = -ENOMEM;Touching this would be a good time to remove the extra space in front of the -ENOMEM :)> + goto free_mem; > + } > > vm_dev->vdev.dev.parent = &pdev->dev; > vm_dev->vdev.dev.release = virtio_mmio_release_dev_empty;(...)> @@ -573,7 +580,18 @@ static int virtio_mmio_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, vm_dev); > > - return register_virtio_device(&vm_dev->vdev); > + rc = register_virtio_device(&vm_dev->vdev); > + if (rc) > + goto unmap; > + return 0; > +unmap: > + iounmap(vm_dev->base); > +free_mem: > + devm_release_mem_region(&pdev->dev, mem->start, > + resource_size(mem)); > +free_vmdev: > + devm_kfree(&pdev->dev, vm_dev);I think this is problematic as vm_dev embeds a struct device (via embedding a struct virtio_device). I think the right way to do this is - call this only if register_virtio_device() has not been called - put the devm_kfree() into the ->release callback for the virtio_device (IOW, replace virtio_mmio_release_dev_empty() with a function that calls this) - do a put_device() if register_virtio_device() failed I might be missing some interaction between the usual driver model handling and devm resources, though.> + return rc; > } > > static int virtio_mmio_remove(struct platform_device *pdev)
weiping zhang
2017-Dec-05 01:36 UTC
[PATCH] virtio_mmio: add cleanup for virtio_mmio_probe
2017-12-04 18:24 GMT+08:00 Cornelia Huck <cohuck at redhat.com>:> On Sat, 2 Dec 2017 01:51:40 +0800 > weiping zhang <zwp10758 at gmail.com> wrote: > >> cleanup all resource allocated by virtio_mmio_probe. >> >> Signed-off-by: weiping zhang <zhangweiping at didichuxing.com> >> --- >> drivers/virtio/virtio_mmio.c | 34 ++++++++++++++++++++++++++-------- >> 1 file changed, 26 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c >> index 74dc717..3fd0e66 100644 >> --- a/drivers/virtio/virtio_mmio.c >> +++ b/drivers/virtio/virtio_mmio.c >> @@ -513,8 +513,10 @@ static int virtio_mmio_probe(struct platform_device *pdev) >> return -EBUSY; >> >> vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL); >> - if (!vm_dev) >> - return -ENOMEM; >> + if (!vm_dev) { >> + rc = -ENOMEM; > > Touching this would be a good time to remove the extra space in front > of the -ENOMEM :)Thanks, I fix this at V2.> >> + goto free_mem; >> + } >> >> vm_dev->vdev.dev.parent = &pdev->dev; >> vm_dev->vdev.dev.release = virtio_mmio_release_dev_empty; > > (...) > >> @@ -573,7 +580,18 @@ static int virtio_mmio_probe(struct platform_device *pdev) >> >> platform_set_drvdata(pdev, vm_dev); >> >> - return register_virtio_device(&vm_dev->vdev); >> + rc = register_virtio_device(&vm_dev->vdev); >> + if (rc) >> + goto unmap; >> + return 0; >> +unmap: >> + iounmap(vm_dev->base); >> +free_mem: >> + devm_release_mem_region(&pdev->dev, mem->start, >> + resource_size(mem)); >> +free_vmdev: >> + devm_kfree(&pdev->dev, vm_dev); > > I think this is problematic as vm_dev embeds a struct device (via > embedding a struct virtio_device). I think the right way to do this is > - call this only if register_virtio_device() has not been called > - put the devm_kfree() into the ->release callback for the > virtio_device (IOW, replace virtio_mmio_release_dev_empty() with a > function that calls this) > - do a put_device() if register_virtio_device() failed > > I might be missing some interaction between the usual driver model > handling and devm resources, though. >if fail in virtio_mmio_probe, we need free @mem of @pdev, vdev->base, so I prefer clean all this resource in virtio_mmio_probe itself, keep vdev.dev.release do nothing. also we need release these resources at virtio_mmio_remove. I'll send V2. -- thanks a ton