From 7a37f55af7af868119b4fb69285f5fa03ba8cf35 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 5 Aug 2025 17:10:56 +0200 Subject: fuse: add COPY_FILE_RANGE_64 that allows large copies The FUSE protocol uses struct fuse_write_out to convey the return value of copy_file_range, which is restricted to uint32_t. But the COPY_FILE_RANGE interface supports a 64-bit size copies and there's no reason why copies should be limited to 32-bit. Introduce a new op COPY_FILE_RANGE_64, which is identical, except the number of bytes copied is returned in a 64-bit value. If the fuse server does not support COPY_FILE_RANGE_64, fall back to COPY_FILE_RANGE. Reported-by: Florian Weimer Closes: https://lore.kernel.org/all/lhuh5ynl8z5.fsf@oldenburg.str.redhat.com/ Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 122d6586e8d4..94621f68a5cc 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -235,6 +235,10 @@ * * 7.44 * - add FUSE_NOTIFY_INC_EPOCH + * + * 7.45 + * - add FUSE_COPY_FILE_RANGE_64 + * - add struct fuse_copy_file_range_out */ #ifndef _LINUX_FUSE_H @@ -270,7 +274,7 @@ #define FUSE_KERNEL_VERSION 7 /** Minor version number of this interface */ -#define FUSE_KERNEL_MINOR_VERSION 44 +#define FUSE_KERNEL_MINOR_VERSION 45 /** The node ID of the root inode */ #define FUSE_ROOT_ID 1 @@ -657,6 +661,7 @@ enum fuse_opcode { FUSE_SYNCFS = 50, FUSE_TMPFILE = 51, FUSE_STATX = 52, + FUSE_COPY_FILE_RANGE_64 = 53, /* CUSE specific operations */ CUSE_INIT = 4096, @@ -1148,6 +1153,11 @@ struct fuse_copy_file_range_in { uint64_t flags; }; +/* For FUSE_COPY_FILE_RANGE_64 */ +struct fuse_copy_file_range_out { + uint64_t bytes_copied; +}; + #define FUSE_SETUPMAPPING_FLAG_WRITE (1ull << 0) #define FUSE_SETUPMAPPING_FLAG_READ (1ull << 1) struct fuse_setupmapping_in { -- cgit v1.2.3 From dfb84c33079497bf27058b15780e1c7bba4c371b Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Fri, 22 Aug 2025 13:10:44 +0200 Subject: fuse: allow synchronous FUSE_INIT FUSE_INIT has always been asynchronous with mount. That means that the server processed this request after the mount syscall returned. This means that FUSE_INIT can't supply the root inode's ID, hence it currently has a hardcoded value. There are other limitations such as not being able to perform getxattr during mount, which is needed by selinux. To remove these limitations allow server to process FUSE_INIT while initializing the in-core super block for the fuse filesystem. This can only be done if the server is prepared to handle this, so add FUSE_DEV_IOC_SYNC_INIT ioctl, which a) lets the server know whether this feature is supported, returning ENOTTY othewrwise. b) lets the kernel know to perform a synchronous initialization The implementation is slightly tricky, since fuse_dev/fuse_conn are set up only during super block creation. This is solved by setting the private data of the fuse device file to a special value ((struct fuse_dev *) 1) and waiting for this to be turned into a proper fuse_dev before commecing with operations on the device file. Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 94621f68a5cc..6b9fb8b08768 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -1131,6 +1131,7 @@ struct fuse_backing_map { #define FUSE_DEV_IOC_BACKING_OPEN _IOW(FUSE_DEV_IOC_MAGIC, 1, \ struct fuse_backing_map) #define FUSE_DEV_IOC_BACKING_CLOSE _IOW(FUSE_DEV_IOC_MAGIC, 2, uint32_t) +#define FUSE_DEV_IOC_SYNC_INIT _IO(FUSE_DEV_IOC_MAGIC, 3) struct fuse_lseek_in { uint64_t fh; -- cgit v1.2.3 From 0a0fdb98d16e334e259352893462030f15fb887f Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 26 Aug 2025 17:08:19 +0200 Subject: fuse: remove FUSE_NOTIFY_CODE_MAX from Constants that change value from version to version have no place in an interface definition. Hopefully this won't break anything. Reviewed-by: Joanne Koong Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 6b9fb8b08768..30bf0846547f 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -680,7 +680,6 @@ enum fuse_notify_code { FUSE_NOTIFY_DELETE = 6, FUSE_NOTIFY_RESEND = 7, FUSE_NOTIFY_INC_EPOCH = 8, - FUSE_NOTIFY_CODE_MAX, }; /* The read buffer is required to be at least 8k, but may be much larger */ -- cgit v1.2.3 From 3f29d59e92a96d843c2ff10ebfed92ac26878658 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 2 Sep 2025 10:22:06 +0200 Subject: fuse: add prune notification Some fuse servers need to prune their caches, which can only be done if the kernel's own dentry/inode caches are pruned first to avoid dangling references. Add FUSE_NOTIFY_PRUNE, which takes an array of node ID's to try and get rid of. Inodes with active references are skipped. A similar functionality is already provided by FUSE_NOTIFY_INVAL_ENTRY with the FUSE_EXPIRE_ONLY flag. Differences in the interface are FUSE_NOTIFY_INVAL_ENTRY: - can only prune one dentry - dentry is determined by parent ID and name - if inode has multiple aliases (cached hard links), then they would have to be invalidated individually to be able to get rid of the inode FUSE_NOTIFY_PRUNE: - can prune multiple inodes - inodes determined by their node ID - aliases are taken care of automatically Reviewed-by: Joanne Koong Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 30bf0846547f..c13e1f9a2f12 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -239,6 +239,7 @@ * 7.45 * - add FUSE_COPY_FILE_RANGE_64 * - add struct fuse_copy_file_range_out + * - add FUSE_NOTIFY_PRUNE */ #ifndef _LINUX_FUSE_H @@ -680,6 +681,7 @@ enum fuse_notify_code { FUSE_NOTIFY_DELETE = 6, FUSE_NOTIFY_RESEND = 7, FUSE_NOTIFY_INC_EPOCH = 8, + FUSE_NOTIFY_PRUNE = 9, }; /* The read buffer is required to be at least 8k, but may be much larger */ @@ -1118,6 +1120,12 @@ struct fuse_notify_retrieve_in { uint64_t dummy4; }; +struct fuse_notify_prune_out { + uint32_t count; + uint32_t padding; + uint64_t spare; +}; + struct fuse_backing_map { int32_t fd; uint32_t flags; -- cgit v1.2.3