diff options
author | Dave Hansen <haveblue@us.ibm.com> | 2008-02-15 14:37:27 -0800 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-19 00:25:31 -0400 |
commit | d57999e1527f0b0c818846dcba5a23015beb4823 (patch) | |
tree | 6cd6f1e773fb19b18531997131b0887f835dcf03 /fs | |
parent | 3925e6fc1f774048404fdd910b0345b06c699eb4 (diff) | |
download | kernel_samsung_smdk4412-d57999e1527f0b0c818846dcba5a23015beb4823.zip kernel_samsung_smdk4412-d57999e1527f0b0c818846dcba5a23015beb4823.tar.gz kernel_samsung_smdk4412-d57999e1527f0b0c818846dcba5a23015beb4823.tar.bz2 |
[PATCH] do namei_flags calculation inside open_namei()
My end goal here is to make sure all users of may_open()
return filps. This will ensure that we properly release
mount write counts which were taken for the filp in
may_open().
This patch moves the sys_open flags to namei flags
calculation into fs/namei.c. We'll shortly be moving
the nameidata_to_filp() calls into namei.c, and this
gets the sys_open flags to a place where we can get
at them when we need them.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/namei.c | 43 | ||||
-rw-r--r-- | fs/open.c | 22 |
2 files changed, 36 insertions, 29 deletions
@@ -1677,7 +1677,12 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) return 0; } -static int open_namei_create(struct nameidata *nd, struct path *path, +/* + * Be careful about ever adding any more callers of this + * function. Its flags must be in the namei format, not + * what get passed to sys_open(). + */ +static int __open_namei_create(struct nameidata *nd, struct path *path, int flag, int mode) { int error; @@ -1696,26 +1701,46 @@ static int open_namei_create(struct nameidata *nd, struct path *path, } /* + * Note that while the flag value (low two bits) for sys_open means: + * 00 - read-only + * 01 - write-only + * 10 - read-write + * 11 - special + * it is changed into + * 00 - no permissions needed + * 01 - read-permission + * 10 - write-permission + * 11 - read-write + * for the internal routines (ie open_namei()/follow_link() etc) + * This is more logical, and also allows the 00 "no perm needed" + * to be used for symlinks (where the permissions are checked + * later). + * +*/ +static inline int open_to_namei_flags(int flag) +{ + if ((flag+1) & O_ACCMODE) + flag++; + return flag; +} + +/* * open_namei() * * namei for open - this is in fact almost the whole open-routine. * * Note that the low bits of "flag" aren't the same as in the open - * system call - they are 00 - no permissions needed - * 01 - read permission needed - * 10 - write permission needed - * 11 - read/write permissions needed - * which is a lot more logical, and also allows the "no perm" needed - * for symlinks (where the permissions are checked later). + * system call. See open_to_namei_flags(). * SMP-safe */ -int open_namei(int dfd, const char *pathname, int flag, +int open_namei(int dfd, const char *pathname, int open_flag, int mode, struct nameidata *nd) { int acc_mode, error; struct path path; struct dentry *dir; int count = 0; + int flag = open_to_namei_flags(open_flag); acc_mode = ACC_MODE(flag); @@ -1776,7 +1801,7 @@ do_last: /* Negative dentry, just create the file */ if (!path.dentry->d_inode) { - error = open_namei_create(nd, &path, flag, mode); + error = __open_namei_create(nd, &path, flag, mode); if (error) goto exit; return 0; @@ -796,31 +796,13 @@ cleanup_file: return ERR_PTR(error); } -/* - * Note that while the flag value (low two bits) for sys_open means: - * 00 - read-only - * 01 - write-only - * 10 - read-write - * 11 - special - * it is changed into - * 00 - no permissions needed - * 01 - read-permission - * 10 - write-permission - * 11 - read-write - * for the internal routines (ie open_namei()/follow_link() etc). 00 is - * used by symlinks. - */ static struct file *do_filp_open(int dfd, const char *filename, int flags, int mode) { - int namei_flags, error; + int error; struct nameidata nd; - namei_flags = flags; - if ((namei_flags+1) & O_ACCMODE) - namei_flags++; - - error = open_namei(dfd, filename, namei_flags, mode, &nd); + error = open_namei(dfd, filename, flags, mode, &nd); if (!error) return nameidata_to_filp(&nd, flags); |