SETUPMAPPING is a command for use with 'virtiofsd', a fuse-over-virtio implementation; it may find use in other fuse impelementations as well in which the kernel does not have access to the address space of the daemon directly. A SETUPMAPPING operation causes a section of a file to be mapped into a memory window visible to the kernel. The offsets in the file and the window are defined by the kernel performing the operation. The daemon may reject the request, for reasons including permissions and limited resources. When a request perfectly overlaps a previous mapping, the previous mapping is replaced. When a mapping partially overlaps a previous mapping, the previous mapping is split into one or two smaller mappings. REMOVEMAPPING is the complement to SETUPMAPPING; it unmaps a range of mapped files from the window visible to the kernel. The map_alignment field communicates the alignment constraint for FUSE_SETUPMAPPING/FUSE_REMOVEMAPPING and allows the daemon to constrain the addresses and file offsets chosen by the kernel.
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| @@ -133,6 +133,8 @@ · 132 unmodified lines | ||
| 133 | 133 | * |
| 134 | 134 | * 7.31 |
| 135 | 135 | * - add FUSE_WRITE_KILL_PRIV flag |
| 136 | + * - add FUSE_SETUPMAPPING and FUSE_REMOVEMAPPING | |
| 137 | + * - add map_alignment to fuse_init_out, add FUSE_MAP_ALIGNMENT flag | |
| 136 | 138 | */ |
| 137 | 139 | |
| 138 | 140 | #ifndef _LINUX_FUSE_H |
| @@ -274,6 +276,7 @@ struct fuse_file_lock { · 135 unmodified lines | ||
| 274 | 276 | * FUSE_CACHE_SYMLINKS: cache READLINK responses |
| 275 | 277 | * FUSE_NO_OPENDIR_SUPPORT: kernel supports zero-message opendir |
| 276 | 278 | * FUSE_EXPLICIT_INVAL_DATA: only invalidate cached pages on explicit request |
| 279 | + * FUSE_MAP_ALIGNMENT: map_alignment field is valid | |
| 277 | 280 | */ |
| 278 | 281 | #define FUSE_ASYNC_READ (1 << 0) |
| 279 | 282 | #define FUSE_POSIX_LOCKS (1 << 1) |
| @@ -301,6 +304,7 @@ struct fuse_file_lock { · 21 unmodified lines | ||
| 301 | 304 | #define FUSE_CACHE_SYMLINKS (1 << 23) |
| 302 | 305 | #define FUSE_NO_OPENDIR_SUPPORT (1 << 24) |
| 303 | 306 | #define FUSE_EXPLICIT_INVAL_DATA (1 << 25) |
| 307 | +#define FUSE_MAP_ALIGNMENT (1 << 26) | |
| 304 | 308 | |
| 305 | 309 | /** |
| 306 | 310 | * CUSE INIT request/reply flags |
| @@ -422,6 +426,8 @@ enum fuse_opcode { · 115 unmodified lines | ||
| 422 | 426 | FUSE_RENAME2 = 45, |
| 423 | 427 | FUSE_LSEEK = 46, |
| 424 | 428 | FUSE_COPY_FILE_RANGE = 47, |
| 429 | + FUSE_SETUPMAPPING = 48, | |
| 430 | + FUSE_REMOVEMAPPING = 49, | |
| 425 | 431 | |
| 426 | 432 | /* CUSE specific operations */ |
| 427 | 433 | CUSE_INIT = 4096, |
| @@ -656,7 +662,7 @@ struct fuse_init_out { · 228 unmodified lines | ||
| 656 | 662 | uint32_t max_write; |
| 657 | 663 | uint32_t time_gran; |
| 658 | 664 | uint16_t max_pages; |
| 659 | − uint16_t padding; | |
| 665 | + uint16_t map_alignment; | |
| 660 | 666 | uint32_t unused[8]; |
| 661 | 667 | }; |
| 662 | 668 | |