| Message ID | 20240425215803.24267-1-linux@osuchow.ski (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] fs: Create anon_inode_getfile_fmode() | expand |
On Thu, Apr 25, 2024 at 11:58:03PM +0200, Dawid Osuchowski wrote: > +struct file *anon_inode_getfile_fmode(const char *name, > + const struct file_operations *fops, > + void *priv, int flags, fmode_t f_mode) ^^^^^^^ > +struct file *anon_inode_getfile_fmode(const char *name, > + const struct file_operations *fops, > + void *priv, int flags, unsigned int f_mode); ^^^^^^^^^^^^ They ought to match (and fmode_t is the right type here).
On 4/26/24 00:03, Al Viro wrote: > On Thu, Apr 25, 2024 at 11:58:03PM +0200, Dawid Osuchowski wrote: >> +struct file *anon_inode_getfile_fmode(const char *name, >> + const struct file_operations *fops, >> + void *priv, int flags, fmode_t f_mode) > ^^^^^^^ >> +struct file *anon_inode_getfile_fmode(const char *name, >> + const struct file_operations *fops, >> + void *priv, int flags, unsigned int f_mode); > ^^^^^^^^^^^^ > > They ought to match (and fmode_t is the right type here). Should I include the <linux/fs.h> header (or a different one) into anon_inodes.h to get the fmode_t type or can I copy the typedef directly as a sort of "forward declare" instead? The latter would mean something like this: struct inode; + typedef unsigned int fmode_t; -- Dawid
On Fri, Apr 26, 2024 at 12:15:52AM +0200, Dawid Osuchowski wrote: > On 4/26/24 00:03, Al Viro wrote: > > On Thu, Apr 25, 2024 at 11:58:03PM +0200, Dawid Osuchowski wrote: > > > +struct file *anon_inode_getfile_fmode(const char *name, > > > + const struct file_operations *fops, > > > + void *priv, int flags, fmode_t f_mode) > > ^^^^^^^ > > > +struct file *anon_inode_getfile_fmode(const char *name, > > > + const struct file_operations *fops, > > > + void *priv, int flags, unsigned int f_mode); > > ^^^^^^^^^^^^ > > > > They ought to match (and fmode_t is the right type here). > > Should I include the <linux/fs.h> header (or a different one) into > anon_inodes.h to get the fmode_t type or can I copy the typedef directly as > a sort of "forward declare" instead? > > The latter would mean something like this: > > struct inode; > + typedef unsigned int fmode_t; linux/types.h, if anything.
On 4/26/24 00:31, Al Viro wrote:
> linux/types.h, if anything.
Thanks, will address in next revision.
-- Dawid
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c index 0496cb5b6eab..42bd1cb7c9cd 100644 --- a/fs/anon_inodes.c +++ b/fs/anon_inodes.c @@ -148,6 +148,38 @@ struct file *anon_inode_getfile(const char *name, } EXPORT_SYMBOL_GPL(anon_inode_getfile); +/** + * anon_inode_getfile_fmode - creates a new file instance by hooking it up to an + * anonymous inode, and a dentry that describe the "class" + * of the file + * + * @name: [in] name of the "class" of the new file + * @fops: [in] file operations for the new file + * @priv: [in] private data for the new file (will be file's private_data) + * @flags: [in] flags + * @f_mode: [in] fmode + * + * Creates a new file by hooking it on a single inode. This is useful for files + * that do not need to have a full-fledged inode in order to operate correctly. + * All the files created with anon_inode_getfile() will share a single inode, + * hence saving memory and avoiding code duplication for the file/inode/dentry + * setup. Allows setting the fmode. Returns the newly created file* or an error + * pointer. + */ +struct file *anon_inode_getfile_fmode(const char *name, + const struct file_operations *fops, + void *priv, int flags, fmode_t f_mode) +{ + struct file *file; + + file = __anon_inode_getfile(name, fops, priv, flags, NULL, false); + if (!IS_ERR(file)) + file->f_mode |= f_mode; + + return file; +} +EXPORT_SYMBOL_GPL(anon_inode_getfile_fmode); + /** * anon_inode_create_getfile - Like anon_inode_getfile(), but creates a new * !S_PRIVATE anon inode rather than reuse the @@ -271,6 +303,7 @@ int anon_inode_create_getfd(const char *name, const struct file_operations *fops return __anon_inode_getfd(name, fops, priv, flags, context_inode, true); } + static int __init anon_inode_init(void) { anon_inode_mnt = kern_mount(&anon_inode_fs_type); diff --git a/include/linux/anon_inodes.h b/include/linux/anon_inodes.h index 93a5f16d03f3..ee55f9c11a16 100644 --- a/include/linux/anon_inodes.h +++ b/include/linux/anon_inodes.h @@ -15,6 +15,9 @@ struct inode; struct file *anon_inode_getfile(const char *name, const struct file_operations *fops, void *priv, int flags); +struct file *anon_inode_getfile_fmode(const char *name, + const struct file_operations *fops, + void *priv, int flags, unsigned int f_mode); struct file *anon_inode_create_getfile(const char *name, const struct file_operations *fops, void *priv, int flags,
Creates an anon_inode_getfile_fmode() function that works similarly to anon_inode_getfile() with the addition of being able to set the fmode member. Signed-off-by: Dawid Osuchowski <linux@osuchow.ski> --- Changes since v1: * removed __anon_inode_create_getfile_fmode() * streamlined if statement and got rid of goto --- fs/anon_inodes.c | 33 +++++++++++++++++++++++++++++++++ include/linux/anon_inodes.h | 3 +++ 2 files changed, 36 insertions(+)