From e1706f0764f8bea42db8d33df5d7f9e754b89693 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:18:57 -0300 Subject: vfio/samples: Remove module get/put The patch to move the get/put to core and the patch to convert the samples to use vfio_device crossed in a way that this was missed. When both patches are together the samples do not need their own get/put. Fixes: 437e41368c01 ("vfio/mdpy: Convert to use vfio_register_group_dev()") Fixes: 681c1615f891 ("vfio/mbochs: Convert to use vfio_register_group_dev()") Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Reviewed-by: Max Gurtovoy Link: https://lore.kernel.org/r/1-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- samples/vfio-mdev/mbochs.c | 4 ---- samples/vfio-mdev/mdpy.c | 4 ---- 2 files changed, 8 deletions(-) (limited to 'samples') diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c index 6c0f229db36a..e81b875b4d87 100644 --- a/samples/vfio-mdev/mbochs.c +++ b/samples/vfio-mdev/mbochs.c @@ -1274,9 +1274,6 @@ static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd, static int mbochs_open(struct vfio_device *vdev) { - if (!try_module_get(THIS_MODULE)) - return -ENODEV; - return 0; } @@ -1300,7 +1297,6 @@ static void mbochs_close(struct vfio_device *vdev) mbochs_put_pages(mdev_state); mutex_unlock(&mdev_state->ops_lock); - module_put(THIS_MODULE); } static ssize_t diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index 393c9df6f6a0..a7d4ed28d664 100644 --- a/samples/vfio-mdev/mdpy.c +++ b/samples/vfio-mdev/mdpy.c @@ -611,15 +611,11 @@ static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd, static int mdpy_open(struct vfio_device *vdev) { - if (!try_module_get(THIS_MODULE)) - return -ENODEV; - return 0; } static void mdpy_close(struct vfio_device *vdev) { - module_put(THIS_MODULE); } static ssize_t -- cgit v1.2.3 From de5494af4815a4c9328536c72741229b7de88e7f Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:18:58 -0300 Subject: vfio/mbochs: Fix missing error unwind of mbochs_used_mbytes Convert mbochs to use an atomic scheme for this like mtty was changed into. The atomic fixes various race conditions with probing. Add the missing error unwind. Also add the missing kfree of mdev_state->pages. Fixes: 681c1615f891 ("vfio/mbochs: Convert to use vfio_register_group_dev()") Reported-by: Cornelia Huck Co-developed-by: Alex Williamson Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/2-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- samples/vfio-mdev/mbochs.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) (limited to 'samples') diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c index e81b875b4d87..3e885be7d076 100644 --- a/samples/vfio-mdev/mbochs.c +++ b/samples/vfio-mdev/mbochs.c @@ -129,7 +129,7 @@ static dev_t mbochs_devt; static struct class *mbochs_class; static struct cdev mbochs_cdev; static struct device mbochs_dev; -static int mbochs_used_mbytes; +static atomic_t mbochs_avail_mbytes; static const struct vfio_device_ops mbochs_dev_ops; struct vfio_region_info_ext { @@ -507,18 +507,22 @@ static int mbochs_reset(struct mdev_state *mdev_state) static int mbochs_probe(struct mdev_device *mdev) { + int avail_mbytes = atomic_read(&mbochs_avail_mbytes); const struct mbochs_type *type = &mbochs_types[mdev_get_type_group_id(mdev)]; struct device *dev = mdev_dev(mdev); struct mdev_state *mdev_state; int ret = -ENOMEM; - if (type->mbytes + mbochs_used_mbytes > max_mbytes) - return -ENOMEM; + do { + if (avail_mbytes < type->mbytes) + return -ENOSPC; + } while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes, + avail_mbytes - type->mbytes)); mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL); if (mdev_state == NULL) - return -ENOMEM; + goto err_avail; vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mbochs_dev_ops); mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL); @@ -549,17 +553,17 @@ static int mbochs_probe(struct mdev_device *mdev) mbochs_create_config_space(mdev_state); mbochs_reset(mdev_state); - mbochs_used_mbytes += type->mbytes; - ret = vfio_register_group_dev(&mdev_state->vdev); if (ret) goto err_mem; dev_set_drvdata(&mdev->dev, mdev_state); return 0; - err_mem: + kfree(mdev_state->pages); kfree(mdev_state->vconfig); kfree(mdev_state); +err_avail: + atomic_add(type->mbytes, &mbochs_avail_mbytes); return ret; } @@ -567,8 +571,8 @@ static void mbochs_remove(struct mdev_device *mdev) { struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev); - mbochs_used_mbytes -= mdev_state->type->mbytes; vfio_unregister_group_dev(&mdev_state->vdev); + atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes); kfree(mdev_state->pages); kfree(mdev_state->vconfig); kfree(mdev_state); @@ -1351,7 +1355,7 @@ static ssize_t available_instances_show(struct mdev_type *mtype, { const struct mbochs_type *type = &mbochs_types[mtype_get_type_group_id(mtype)]; - int count = (max_mbytes - mbochs_used_mbytes) / type->mbytes; + int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes; return sprintf(buf, "%d\n", count); } @@ -1433,6 +1437,8 @@ static int __init mbochs_dev_init(void) { int ret = 0; + atomic_set(&mbochs_avail_mbytes, max_mbytes); + ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME); if (ret < 0) { pr_err("Error: failed to register mbochs_dev, err: %d\n", ret); -- cgit v1.2.3 From ae03c3771b8cbbed3802ad1153d896c32015c520 Mon Sep 17 00:00:00 2001 From: Max Gurtovoy Date: Thu, 5 Aug 2021 22:18:59 -0300 Subject: vfio: Introduce a vfio_uninit_group_dev() API call This pairs with vfio_init_group_dev() and allows undoing any state that is stored in the vfio_device unrelated to registration. Add appropriately placed calls to all the drivers. The following patch will use this to add pre-registration state for the device set. Signed-off-by: Max Gurtovoy Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- samples/vfio-mdev/mbochs.c | 2 ++ samples/vfio-mdev/mdpy.c | 25 +++++++++++++++---------- samples/vfio-mdev/mtty.c | 27 ++++++++++++++++----------- 3 files changed, 33 insertions(+), 21 deletions(-) (limited to 'samples') diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c index 3e885be7d076..0f1511849b7c 100644 --- a/samples/vfio-mdev/mbochs.c +++ b/samples/vfio-mdev/mbochs.c @@ -559,6 +559,7 @@ static int mbochs_probe(struct mdev_device *mdev) dev_set_drvdata(&mdev->dev, mdev_state); return 0; err_mem: + vfio_uninit_group_dev(&mdev_state->vdev); kfree(mdev_state->pages); kfree(mdev_state->vconfig); kfree(mdev_state); @@ -572,6 +573,7 @@ static void mbochs_remove(struct mdev_device *mdev) struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev); vfio_unregister_group_dev(&mdev_state->vdev); + vfio_uninit_group_dev(&mdev_state->vdev); atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes); kfree(mdev_state->pages); kfree(mdev_state->vconfig); diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index a7d4ed28d664..57334034cde6 100644 --- a/samples/vfio-mdev/mdpy.c +++ b/samples/vfio-mdev/mdpy.c @@ -235,17 +235,16 @@ static int mdpy_probe(struct mdev_device *mdev) mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL); if (mdev_state->vconfig == NULL) { - kfree(mdev_state); - return -ENOMEM; + ret = -ENOMEM; + goto err_state; } fbsize = roundup_pow_of_two(type->width * type->height * type->bytepp); mdev_state->memblk = vmalloc_user(fbsize); if (!mdev_state->memblk) { - kfree(mdev_state->vconfig); - kfree(mdev_state); - return -ENOMEM; + ret = -ENOMEM; + goto err_vconfig; } dev_info(dev, "%s: %s (%dx%d)\n", __func__, type->name, type->width, type->height); @@ -260,13 +259,18 @@ static int mdpy_probe(struct mdev_device *mdev) mdpy_count++; ret = vfio_register_group_dev(&mdev_state->vdev); - if (ret) { - kfree(mdev_state->vconfig); - kfree(mdev_state); - return ret; - } + if (ret) + goto err_mem; dev_set_drvdata(&mdev->dev, mdev_state); return 0; +err_mem: + vfree(mdev_state->memblk); +err_vconfig: + kfree(mdev_state->vconfig); +err_state: + vfio_uninit_group_dev(&mdev_state->vdev); + kfree(mdev_state); + return ret; } static void mdpy_remove(struct mdev_device *mdev) @@ -278,6 +282,7 @@ static void mdpy_remove(struct mdev_device *mdev) vfio_unregister_group_dev(&mdev_state->vdev); vfree(mdev_state->memblk); kfree(mdev_state->vconfig); + vfio_uninit_group_dev(&mdev_state->vdev); kfree(mdev_state); mdpy_count--; diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c index 8b26fecc4afe..37cc9067e160 100644 --- a/samples/vfio-mdev/mtty.c +++ b/samples/vfio-mdev/mtty.c @@ -718,8 +718,8 @@ static int mtty_probe(struct mdev_device *mdev) mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL); if (mdev_state == NULL) { - atomic_add(nr_ports, &mdev_avail_ports); - return -ENOMEM; + ret = -ENOMEM; + goto err_nr_ports; } vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mtty_dev_ops); @@ -732,9 +732,8 @@ static int mtty_probe(struct mdev_device *mdev) mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL); if (mdev_state->vconfig == NULL) { - kfree(mdev_state); - atomic_add(nr_ports, &mdev_avail_ports); - return -ENOMEM; + ret = -ENOMEM; + goto err_state; } mutex_init(&mdev_state->ops_lock); @@ -743,14 +742,19 @@ static int mtty_probe(struct mdev_device *mdev) mtty_create_config_space(mdev_state); ret = vfio_register_group_dev(&mdev_state->vdev); - if (ret) { - kfree(mdev_state); - atomic_add(nr_ports, &mdev_avail_ports); - return ret; - } - + if (ret) + goto err_vconfig; dev_set_drvdata(&mdev->dev, mdev_state); return 0; + +err_vconfig: + kfree(mdev_state->vconfig); +err_state: + vfio_uninit_group_dev(&mdev_state->vdev); + kfree(mdev_state); +err_nr_ports: + atomic_add(nr_ports, &mdev_avail_ports); + return ret; } static void mtty_remove(struct mdev_device *mdev) @@ -761,6 +765,7 @@ static void mtty_remove(struct mdev_device *mdev) vfio_unregister_group_dev(&mdev_state->vdev); kfree(mdev_state->vconfig); + vfio_uninit_group_dev(&mdev_state->vdev); kfree(mdev_state); atomic_add(nr_ports, &mdev_avail_ports); } -- cgit v1.2.3 From 17a1e4fa3f7f07f541c751745b5aa6f2fcab9a48 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:19:01 -0300 Subject: vfio/samples: Delete useless open/close The core code no longer requires these ops to be defined, so delete these empty functions and leave the op as NULL. mtty's functions only log a pointless message, delete that entirely. Signed-off-by: Yishai Hadas Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/5-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- samples/vfio-mdev/mbochs.c | 6 ------ samples/vfio-mdev/mdpy.c | 11 ----------- samples/vfio-mdev/mtty.c | 13 ------------- 3 files changed, 30 deletions(-) (limited to 'samples') diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c index 0f1511849b7c..7b2e12fe7082 100644 --- a/samples/vfio-mdev/mbochs.c +++ b/samples/vfio-mdev/mbochs.c @@ -1278,11 +1278,6 @@ static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd, return -ENOTTY; } -static int mbochs_open(struct vfio_device *vdev) -{ - return 0; -} - static void mbochs_close(struct vfio_device *vdev) { struct mdev_state *mdev_state = @@ -1401,7 +1396,6 @@ static struct attribute_group *mdev_type_groups[] = { }; static const struct vfio_device_ops mbochs_dev_ops = { - .open = mbochs_open, .release = mbochs_close, .read = mbochs_read, .write = mbochs_write, diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index 57334034cde6..8d1a80a0722a 100644 --- a/samples/vfio-mdev/mdpy.c +++ b/samples/vfio-mdev/mdpy.c @@ -614,15 +614,6 @@ static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd, return -ENOTTY; } -static int mdpy_open(struct vfio_device *vdev) -{ - return 0; -} - -static void mdpy_close(struct vfio_device *vdev) -{ -} - static ssize_t resolution_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -717,8 +708,6 @@ static struct attribute_group *mdev_type_groups[] = { }; static const struct vfio_device_ops mdpy_dev_ops = { - .open = mdpy_open, - .release = mdpy_close, .read = mdpy_read, .write = mdpy_write, .ioctl = mdpy_ioctl, diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c index 37cc9067e160..5983cdb16e3d 100644 --- a/samples/vfio-mdev/mtty.c +++ b/samples/vfio-mdev/mtty.c @@ -1207,17 +1207,6 @@ static long mtty_ioctl(struct vfio_device *vdev, unsigned int cmd, return -ENOTTY; } -static int mtty_open(struct vfio_device *vdev) -{ - pr_info("%s\n", __func__); - return 0; -} - -static void mtty_close(struct vfio_device *mdev) -{ - pr_info("%s\n", __func__); -} - static ssize_t sample_mtty_dev_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -1325,8 +1314,6 @@ static struct attribute_group *mdev_type_groups[] = { static const struct vfio_device_ops mtty_dev_ops = { .name = "vfio-mtty", - .open = mtty_open, - .release = mtty_close, .read = mtty_read, .write = mtty_write, .ioctl = mtty_ioctl, -- cgit v1.2.3 From 3cb24827147b75557bddc5b39d63897786935b14 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:19:07 -0300 Subject: vfio/mbochs: Fix close when multiple device FDs are open mbochs_close() iterates over global device state and frees it. Currently this is done every time a device FD is closed, but if multiple device FDs are open this could corrupt other still active FDs. Change this to use close_device() so it only runs on the last close. Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/11-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- samples/vfio-mdev/mbochs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'samples') diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c index 7b2e12fe7082..c313ab4d1f4e 100644 --- a/samples/vfio-mdev/mbochs.c +++ b/samples/vfio-mdev/mbochs.c @@ -1278,7 +1278,7 @@ static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd, return -ENOTTY; } -static void mbochs_close(struct vfio_device *vdev) +static void mbochs_close_device(struct vfio_device *vdev) { struct mdev_state *mdev_state = container_of(vdev, struct mdev_state, vdev); @@ -1396,7 +1396,7 @@ static struct attribute_group *mdev_type_groups[] = { }; static const struct vfio_device_ops mbochs_dev_ops = { - .release = mbochs_close, + .close_device = mbochs_close_device, .read = mbochs_read, .write = mbochs_write, .ioctl = mbochs_ioctl, -- cgit v1.2.3