mirror of
https://github.com/torvalds/linux.git
synced 2024-09-20 23:13:00 +00:00
fda0b98ef0
An mmap request for a file open in passthrough mode, maps the memory directly to the backing file. An mmap of a file in direct io mode, usually uses cached mmap and puts the inode in caching io mode, which denies new passthrough opens of that inode, because caching io mode is conflicting with passthrough io mode. For the same reason, trying to mmap a direct io file, while there is a passthrough file open on the same inode will fail with -ENODEV. An mmap of a file in direct io mode, also needs to wait for parallel dio writes in-progress to complete. If a passthrough file is opened, while an mmap of another direct io file is waiting for parallel dio writes to complete, the wait is aborted and mmap fails with -ENODEV. A FUSE server that uses passthrough and direct io opens on the same inode that may also be mmaped, is advised to provide a backing fd also for the files that are open in direct io mode (i.e. use the flags combination FOPEN_DIRECT_IO | FOPEN_PASSTHROUGH), so that mmap will always use the backing file, even if read/write do not passthrough. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> |
||
|---|---|---|
| .. | ||
| acl.c | ||
| control.c | ||
| cuse.c | ||
| dax.c | ||
| dev.c | ||
| dir.c | ||
| file.c | ||
| fuse_i.h | ||
| inode.c | ||
| ioctl.c | ||
| iomode.c | ||
| Kconfig | ||
| Makefile | ||
| passthrough.c | ||
| readdir.c | ||
| virtio_fs.c | ||
| xattr.c | ||