diff options
| author |   Yi Liu <yi.l.liu@intel.com> | 2023-07-18 06:55:45 -0700 |
|---|---|---|
| committer |   Alex Williamson <alex.williamson@redhat.com> | 2023-07-25 10:19:53 -0600 |
| commit | 1c9dc07487cb0f246075b2d3b305bba91156d376 (patch) | |
| tree | d0c650d7449e67bb9b886d6dcb2350c6436bc28f | |
| parent | vfio: Test kvm pointer in _vfio_device_get_kvm_safe() (diff) | |
| download | wireguard-linux-1c9dc07487cb0f246075b2d3b305bba91156d376.tar.xz wireguard-linux-1c9dc07487cb0f246075b2d3b305bba91156d376.zip | |
iommufd: Add iommufd_ctx_from_fd()
It's common to get a reference to the iommufd context from a given file
descriptor. So adds an API for it. Existing users of this API are compiled
only when IOMMUFD is enabled, so no need to have a stub for the IOMMUFD
disabled case.
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-21-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| -rw-r--r-- | drivers/iommu/iommufd/main.c | 24 | ||||
| -rw-r--r-- | include/linux/iommufd.h | 1 |
2 files changed, 25 insertions, 0 deletions
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 32ce7befc8dd..4bbb20dff430 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -378,6 +378,30 @@ struct iommufd_ctx *iommufd_ctx_from_file(struct file *file) EXPORT_SYMBOL_NS_GPL(iommufd_ctx_from_file, IOMMUFD); /** + * iommufd_ctx_from_fd - Acquires a reference to the iommufd context + * @fd: File descriptor to obtain the reference from + * + * Returns a pointer to the iommufd_ctx, otherwise ERR_PTR. On success + * the caller is responsible to call iommufd_ctx_put(). + */ +struct iommufd_ctx *iommufd_ctx_from_fd(int fd) +{ + struct file *file; + + file = fget(fd); + if (!file) + return ERR_PTR(-EBADF); + + if (file->f_op != &iommufd_fops) { + fput(file); + return ERR_PTR(-EBADFD); + } + /* fget is the same as iommufd_ctx_get() */ + return file->private_data; +} +EXPORT_SYMBOL_NS_GPL(iommufd_ctx_from_fd, IOMMUFD); + +/** * iommufd_ctx_put - Put back a reference * @ictx: Context to put back */ diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 3a3216cb9482..9657c58813dc 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -54,6 +54,7 @@ void iommufd_ctx_get(struct iommufd_ctx *ictx); #if IS_ENABLED(CONFIG_IOMMUFD) struct iommufd_ctx *iommufd_ctx_from_file(struct file *file); +struct iommufd_ctx *iommufd_ctx_from_fd(int fd); void iommufd_ctx_put(struct iommufd_ctx *ictx); bool iommufd_ctx_has_group(struct iommufd_ctx *ictx, struct iommu_group *group); |