The f_op->mmap interface is deprecated, so update uio_info to use its successor, mmap_prepare.
Therefore, replace the uio_info->mmap hook with a new uio_info->mmap_prepare hook, and update its one user, target_core_user, to both specify this new mmap_prepare hook and also to use the new vm_ops->mapped() hook to continue to maintain a correct udev->kref refcount. Then update uio_mmap() to utilise the mmap_prepare compatibility layer to invoke this callback from the uio mmap invocation. Signed-off-by: Lorenzo Stoakes (Oracle) <[email protected]> --- drivers/target/target_core_user.c | 26 ++++++++++++++++++-------- drivers/uio/uio.c | 10 ++++++++-- include/linux/uio_driver.h | 4 ++-- 3 files changed, 28 insertions(+), 12 deletions(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index af95531ddd35..edc2afd5f4ee 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1860,6 +1860,17 @@ static struct page *tcmu_try_get_data_page(struct tcmu_dev *udev, uint32_t dpi) return NULL; } +static int tcmu_vma_mapped(unsigned long start, unsigned long end, pgoff_t pgoff, + const struct file *file, void **vm_private_data) +{ + struct tcmu_dev *udev = *vm_private_data; + + pr_debug("vma_mapped\n"); + + kref_get(&udev->kref); + return 0; +} + static void tcmu_vma_open(struct vm_area_struct *vma) { struct tcmu_dev *udev = vma->vm_private_data; @@ -1919,26 +1930,25 @@ static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf) } static const struct vm_operations_struct tcmu_vm_ops = { + .mapped = tcmu_vma_mapped, .open = tcmu_vma_open, .close = tcmu_vma_close, .fault = tcmu_vma_fault, }; -static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) +static int tcmu_mmap_prepare(struct uio_info *info, struct vm_area_desc *desc) { struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); - vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP); - vma->vm_ops = &tcmu_vm_ops; + vma_desc_set_flags(desc, VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT); + desc->vm_ops = &tcmu_vm_ops; - vma->vm_private_data = udev; + desc->private_data = udev; /* Ensure the mmap is exactly the right size */ - if (vma_pages(vma) != udev->mmap_pages) + if (vma_desc_pages(desc) != udev->mmap_pages) return -EINVAL; - tcmu_vma_open(vma); - return 0; } @@ -2253,7 +2263,7 @@ static int tcmu_configure_device(struct se_device *dev) info->irqcontrol = tcmu_irqcontrol; info->irq = UIO_IRQ_CUSTOM; - info->mmap = tcmu_mmap; + info->mmap_prepare = tcmu_mmap_prepare; info->open = tcmu_open; info->release = tcmu_release; diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index 5a4998e2caf8..1e4ade78ed84 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -850,8 +850,14 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma) goto out; } - if (idev->info->mmap) { - ret = idev->info->mmap(idev->info, vma); + if (idev->info->mmap_prepare) { + struct vm_area_desc desc; + + compat_set_desc_from_vma(&desc, filep, vma); + ret = idev->info->mmap_prepare(idev->info, &desc); + if (ret) + goto out; + ret = __compat_vma_mmap(&desc, vma); goto out; } diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h index 334641e20fb1..02eaac47ac44 100644 --- a/include/linux/uio_driver.h +++ b/include/linux/uio_driver.h @@ -97,7 +97,7 @@ struct uio_device { * @irq_flags: flags for request_irq() * @priv: optional private data * @handler: the device's irq handler - * @mmap: mmap operation for this uio device + * @mmap_prepare: mmap_prepare operation for this uio device * @open: open operation for this uio device * @release: release operation for this uio device * @irqcontrol: disable/enable irqs when 0/1 is written to /dev/uioX @@ -112,7 +112,7 @@ struct uio_info { unsigned long irq_flags; void *priv; irqreturn_t (*handler)(int irq, struct uio_info *dev_info); - int (*mmap)(struct uio_info *info, struct vm_area_struct *vma); + int (*mmap_prepare)(struct uio_info *info, struct vm_area_desc *desc); int (*open)(struct uio_info *info, struct inode *inode); int (*release)(struct uio_info *info, struct inode *inode); int (*irqcontrol)(struct uio_info *info, s32 irq_on); -- 2.53.0
