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author | 2006-01-06 00:11:42 -0800 | |
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committer | 2006-01-06 08:33:32 -0800 | |
commit | b0e15190ead07056ab0c3844a499ff35e66d27cc (patch) | |
tree | 0601a8d68fa051a7ee85d22640e982c0a64f0efc /mm/tiny-shmem.c | |
parent | [PATCH] NOMMU: Provide shared-writable mmap support on ramfs (diff) | |
download | linux-b0e15190ead07056ab0c3844a499ff35e66d27cc.tar.gz linux-b0e15190ead07056ab0c3844a499ff35e66d27cc.tar.bz2 linux-b0e15190ead07056ab0c3844a499ff35e66d27cc.zip |
[PATCH] NOMMU: Make SYSV IPC SHM use ramfs facilities on NOMMU
The attached patch makes the SYSV IPC shared memory facilities use the new
ramfs facilities on a no-MMU kernel.
The following changes are made:
(1) There are now shmem_mmap() and shmem_get_unmapped_area() functions to
allow the IPC SHM facilities to commune with the tiny-shmem and shmem
code.
(2) ramfs files now need resizing using do_truncate() rather than by modifying
the inode size directly (see shmem_file_setup()). This causes ramfs to
attempt to bind a block of pages of sufficient size to the inode.
(3) CONFIG_SYSVIPC is no longer contingent on CONFIG_MMU.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/tiny-shmem.c')
-rw-r--r-- | mm/tiny-shmem.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/mm/tiny-shmem.c b/mm/tiny-shmem.c index b58abcf44ed6..cdc6d431972b 100644 --- a/mm/tiny-shmem.c +++ b/mm/tiny-shmem.c @@ -81,13 +81,19 @@ struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags) goto close_file; d_instantiate(dentry, inode); - inode->i_size = size; inode->i_nlink = 0; /* It is unlinked */ + file->f_vfsmnt = mntget(shm_mnt); file->f_dentry = dentry; file->f_mapping = inode->i_mapping; file->f_op = &ramfs_file_operations; file->f_mode = FMODE_WRITE | FMODE_READ; + + /* notify everyone as to the change of file size */ + error = do_truncate(dentry, size, file); + if (error < 0) + goto close_file; + return file; close_file: @@ -123,3 +129,24 @@ int shmem_unuse(swp_entry_t entry, struct page *page) { return 0; } + +int shmem_mmap(struct file *file, struct vm_area_struct *vma) +{ + file_accessed(file); +#ifndef CONFIG_MMU + return ramfs_nommu_mmap(file, vma); +#else + return 0; +#endif +} + +#ifndef CONFIG_MMU +unsigned long shmem_get_unmapped_area(struct file *file, + unsigned long addr, + unsigned long len, + unsigned long pgoff, + unsigned long flags) +{ + return ramfs_nommu_get_unmapped_area(file, addr, len, pgoff, flags); +} +#endif |