diff options
Diffstat (limited to 'fs/devfs.c')
| -rw-r--r-- | fs/devfs.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/fs/devfs.c b/fs/devfs.c index d088c1a66c..e1893d1bd0 100644 --- a/fs/devfs.c +++ b/fs/devfs.c @@ -94,6 +94,26 @@ static int devfs_protect(struct device_d *_dev, FILE *f, size_t count, loff_t of return cdev->ops->protect(cdev, count, offset + cdev->offset, prot); } +static int devfs_discard_range(struct device_d *dev, FILE *f, loff_t count, + loff_t offset) +{ + struct cdev *cdev = f->priv; + + if (!cdev->ops->discard_range) + return -ENOSYS; + + if (cdev->flags & DEVFS_PARTITION_READONLY) + return -EPERM; + + if (offset >= cdev->size) + return 0; + + if (count + offset > cdev->size) + count = cdev->size - offset; + + return cdev->ops->discard_range(cdev, count, offset + cdev->offset); +} + static int devfs_memmap(struct device_d *_dev, FILE *f, void **map, int flags) { struct cdev *cdev = f->priv; @@ -329,6 +349,7 @@ static struct fs_driver_d devfs_driver = { .truncate = devfs_truncate, .erase = devfs_erase, .protect = devfs_protect, + .discard_range = devfs_discard_range, .memmap = devfs_memmap, .flags = FS_DRIVER_NO_DEV, .drv = { |