| Message ID | 20201128161510.347752-17-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/45] blk-cgroup: fix a hd_struct leak in blkcg_fill_root_iostats | expand |
On 11/28/20 5:14 PM, Christoph Hellwig wrote: > All of the current callers already have a reference, but to prepare for > additional users ensure bdgrab returns NULL if the block device is beeing > freed. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > fs/block_dev.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/fs/block_dev.c b/fs/block_dev.c > index d707ab376da86e..962fabe8a67b83 100644 > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -894,10 +894,14 @@ static struct block_device *bdget(dev_t dev) > /** > * bdgrab -- Grab a reference to an already referenced block device > * @bdev: Block device to grab a reference to. > + * > + * Returns the block_device with an additional reference when successful, > + * or NULL if the inode is already beeing freed. > */ > struct block_device *bdgrab(struct block_device *bdev) > { > - ihold(bdev->bd_inode); > + if (!igrab(bdev->bd_inode)) > + return NULL; > return bdev; > } > EXPORT_SYMBOL(bdgrab); > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
On Sat 28-11-20 17:14:41, Christoph Hellwig wrote: > All of the current callers already have a reference, but to prepare for > additional users ensure bdgrab returns NULL if the block device is beeing ^^^ being > freed. > > Signed-off-by: Christoph Hellwig <hch@lst.de> Otherwise looks good. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/block_dev.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/fs/block_dev.c b/fs/block_dev.c > index d707ab376da86e..962fabe8a67b83 100644 > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -894,10 +894,14 @@ static struct block_device *bdget(dev_t dev) > /** > * bdgrab -- Grab a reference to an already referenced block device > * @bdev: Block device to grab a reference to. > + * > + * Returns the block_device with an additional reference when successful, > + * or NULL if the inode is already beeing freed. > */ > struct block_device *bdgrab(struct block_device *bdev) > { > - ihold(bdev->bd_inode); > + if (!igrab(bdev->bd_inode)) > + return NULL; > return bdev; > } > EXPORT_SYMBOL(bdgrab); > -- > 2.29.2 >
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
diff --git a/fs/block_dev.c b/fs/block_dev.c index d707ab376da86e..962fabe8a67b83 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -894,10 +894,14 @@ static struct block_device *bdget(dev_t dev) /** * bdgrab -- Grab a reference to an already referenced block device * @bdev: Block device to grab a reference to. + * + * Returns the block_device with an additional reference when successful, + * or NULL if the inode is already beeing freed. */ struct block_device *bdgrab(struct block_device *bdev) { - ihold(bdev->bd_inode); + if (!igrab(bdev->bd_inode)) + return NULL; return bdev; } EXPORT_SYMBOL(bdgrab);
All of the current callers already have a reference, but to prepare for additional users ensure bdgrab returns NULL if the block device is beeing freed. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/block_dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)