diff options
| author | Alexey Dobriyan <adobriyan@sw.ru> | 2007-10-16 23:26:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-17 08:42:46 -0700 |
| commit | e4dc1b14d8dc57c3975bf69740e4f5cda6bfba09 (patch) | |
| tree | 084771b19ecb4335c31cdd91093f7a02b7861e69 /fs | |
| parent | deba0f49b9345f885a53a077623a68cef89c01d5 (diff) | |
Use list_head in binfmt handling
Switch single-linked binfmt formats list to usual list_head's. This leads
to one-liners in register_binfmt() and unregister_binfmt(). The downside
is one pointer more in struct linux_binfmt. This is not a problem, since
the set of registered binfmts on typical box is very small -- (ELF +
something distro enabled for you).
Test-booted, played with executable .txt files, modprobe/rmmod binfmt_misc.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 34 |
1 files changed, 6 insertions, 28 deletions
diff --git a/fs/exec.c b/fs/exec.c index 073b0b8c6d0..65825bdc447 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -66,27 +66,15 @@ int suid_dumpable = 0; EXPORT_SYMBOL(suid_dumpable); /* The maximal length of core_pattern is also specified in sysctl.c */ -static struct linux_binfmt *formats; +static LIST_HEAD(formats); static DEFINE_RWLOCK(binfmt_lock); int register_binfmt(struct linux_binfmt * fmt) { - struct linux_binfmt ** tmp = &formats; - if (!fmt) return -EINVAL; - if (fmt->next) - return -EBUSY; write_lock(&binfmt_lock); - while (*tmp) { - if (fmt == *tmp) { - write_unlock(&binfmt_lock); - return -EBUSY; - } - tmp = &(*tmp)->next; - } - fmt->next = formats; - formats = fmt; + list_add(&fmt->lh, &formats); write_unlock(&binfmt_lock); return 0; } @@ -95,20 +83,10 @@ EXPORT_SYMBOL(register_binfmt); int unregister_binfmt(struct linux_binfmt * fmt) { - struct linux_binfmt ** tmp = &formats; - write_lock(&binfmt_lock); - while (*tmp) { - if (fmt == *tmp) { - *tmp = fmt->next; - fmt->next = NULL; - write_unlock(&binfmt_lock); - return 0; - } - tmp = &(*tmp)->next; - } + list_del(&fmt->lh); write_unlock(&binfmt_lock); - return -EINVAL; + return 0; } EXPORT_SYMBOL(unregister_binfmt); @@ -155,7 +133,7 @@ asmlinkage long sys_uselib(const char __user * library) struct linux_binfmt * fmt; read_lock(&binfmt_lock); - for (fmt = formats ; fmt ; fmt = fmt->next) { + list_for_each_entry(fmt, &formats, lh) { if (!fmt->load_shlib) continue; if (!try_module_get(fmt->module)) @@ -1284,7 +1262,7 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) retval = -ENOENT; for (try=0; try<2; try++) { read_lock(&binfmt_lock); - for (fmt = formats ; fmt ; fmt = fmt->next) { + list_for_each_entry(fmt, &formats, lh) { int (*fn)(struct linux_binprm *, struct pt_regs *) = fmt->load_binary; if (!fn) continue; |