| Message ID | 20200819083259.919838-1-leon@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs: Add function declaration of simple_dname | expand |
On Wed, Aug 19, 2020 at 11:32:59AM +0300, Leon Romanovsky wrote: > From: Leon Romanovsky <leonro@nvidia.com> > > The simple_dname() is declared in internal header file as extern > and this generates the following GCC warning. The fact that it's declared as extern doesn't matter. You don't need the change to internal.h at all. The use of 'extern' on a function declaration is purely decorative: 5 If the declaration of an identifier for a function has no storage-class specifier, its linkage is determined exactly as if it were declared with the storage-class specifier extern. I'd drop the change to internal.h and fix the changelog. > fs/d_path.c:311:7: warning: no previous prototype for 'simple_dname' [-Wmissing-prototypes] > 311 | char *simple_dname(struct dentry *dentry, char *buffer, int buflen) > | ^~~~~~~~~~~~ > > Instead of that extern, reuse the fact that internal.h file is internal to fs/* and > declare simple_dname() like any other function. > > Fixes: 7e5f7bb08b8c ("unexport simple_dname()") > Signed-off-by: Leon Romanovsky <leonro@nvidia.com> > --- > fs/d_path.c | 2 ++ > fs/internal.h | 2 +- > 2 files changed, 3 insertions(+), 1 deletion(-) > > diff --git a/fs/d_path.c b/fs/d_path.c > index 0f1fc1743302..4b89448cc78e 100644 > --- a/fs/d_path.c > +++ b/fs/d_path.c > @@ -8,6 +8,8 @@ > #include <linux/prefetch.h> > #include "mount.h" > > +#include "internal.h" > + > static int prepend(char **buffer, int *buflen, const char *str, int namelen) > { > *buflen -= namelen; > diff --git a/fs/internal.h b/fs/internal.h > index 10517ece4516..2def264272f4 100644 > --- a/fs/internal.h > +++ b/fs/internal.h > @@ -164,7 +164,7 @@ extern int d_set_mounted(struct dentry *dentry); > extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc); > extern struct dentry *d_alloc_cursor(struct dentry *); > extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); > -extern char *simple_dname(struct dentry *, char *, int); > +char *simple_dname(struct dentry *d, char *buf, int len); > extern void dput_to_list(struct dentry *, struct list_head *); > extern void shrink_dentry_list(struct list_head *); > > -- > 2.26.2 >
On Wed, Aug 19, 2020 at 12:34:24PM +0100, Matthew Wilcox wrote: > On Wed, Aug 19, 2020 at 11:32:59AM +0300, Leon Romanovsky wrote: > > From: Leon Romanovsky <leonro@nvidia.com> > > > > The simple_dname() is declared in internal header file as extern > > and this generates the following GCC warning. > > The fact that it's declared as extern doesn't matter. You don't need > the change to internal.h at all. The use of 'extern' on a function > declaration is purely decorative: > > 5 If the declaration of an identifier for a function has no > storage-class specifier, its linkage is determined exactly as if it > were declared with the storage-class specifier extern. So why do we need to keep extern keyword if we use intenral.h directly? > > I'd drop the change to internal.h and fix the changelog. Thanks > > > fs/d_path.c:311:7: warning: no previous prototype for 'simple_dname' [-Wmissing-prototypes] > > 311 | char *simple_dname(struct dentry *dentry, char *buffer, int buflen) > > | ^~~~~~~~~~~~ > > > > Instead of that extern, reuse the fact that internal.h file is internal to fs/* and > > declare simple_dname() like any other function. > > > > Fixes: 7e5f7bb08b8c ("unexport simple_dname()") > > Signed-off-by: Leon Romanovsky <leonro@nvidia.com> > > --- > > fs/d_path.c | 2 ++ > > fs/internal.h | 2 +- > > 2 files changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/fs/d_path.c b/fs/d_path.c > > index 0f1fc1743302..4b89448cc78e 100644 > > --- a/fs/d_path.c > > +++ b/fs/d_path.c > > @@ -8,6 +8,8 @@ > > #include <linux/prefetch.h> > > #include "mount.h" > > > > +#include "internal.h" > > + > > static int prepend(char **buffer, int *buflen, const char *str, int namelen) > > { > > *buflen -= namelen; > > diff --git a/fs/internal.h b/fs/internal.h > > index 10517ece4516..2def264272f4 100644 > > --- a/fs/internal.h > > +++ b/fs/internal.h > > @@ -164,7 +164,7 @@ extern int d_set_mounted(struct dentry *dentry); > > extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc); > > extern struct dentry *d_alloc_cursor(struct dentry *); > > extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); > > -extern char *simple_dname(struct dentry *, char *, int); > > +char *simple_dname(struct dentry *d, char *buf, int len); > > extern void dput_to_list(struct dentry *, struct list_head *); > > extern void shrink_dentry_list(struct list_head *); > > > > -- > > 2.26.2 > >
On Wed, Aug 19, 2020 at 02:40:01PM +0300, Leon Romanovsky wrote: > On Wed, Aug 19, 2020 at 12:34:24PM +0100, Matthew Wilcox wrote: > > On Wed, Aug 19, 2020 at 11:32:59AM +0300, Leon Romanovsky wrote: > > > From: Leon Romanovsky <leonro@nvidia.com> > > > > > > The simple_dname() is declared in internal header file as extern > > > and this generates the following GCC warning. > > > > The fact that it's declared as extern doesn't matter. You don't need > > the change to internal.h at all. The use of 'extern' on a function > > declaration is purely decorative: > > > > 5 If the declaration of an identifier for a function has no > > storage-class specifier, its linkage is determined exactly as if it > > were declared with the storage-class specifier extern. > > So why do we need to keep extern keyword if we use intenral.h directly? We don't. It's just personal preference. I don't use extern keywords on function declarations anywhere, but Al does and it's rude to change it.
On Wed, Aug 19, 2020 at 12:47:55PM +0100, Matthew Wilcox wrote: > On Wed, Aug 19, 2020 at 02:40:01PM +0300, Leon Romanovsky wrote: > > On Wed, Aug 19, 2020 at 12:34:24PM +0100, Matthew Wilcox wrote: > > > On Wed, Aug 19, 2020 at 11:32:59AM +0300, Leon Romanovsky wrote: > > > > From: Leon Romanovsky <leonro@nvidia.com> > > > > > > > > The simple_dname() is declared in internal header file as extern > > > > and this generates the following GCC warning. > > > > > > The fact that it's declared as extern doesn't matter. You don't need > > > the change to internal.h at all. The use of 'extern' on a function > > > declaration is purely decorative: > > > > > > 5 If the declaration of an identifier for a function has no > > > storage-class specifier, its linkage is determined exactly as if it > > > were declared with the storage-class specifier extern. > > > > So why do we need to keep extern keyword if we use intenral.h directly? > > We don't. It's just personal preference. I don't use extern keywords > on function declarations anywhere, but Al does and it's rude to change it. I didn't have any intention to be rude, just like you, I don't use extern keyword. I'll resend to make a progress. Thanks >
diff --git a/fs/d_path.c b/fs/d_path.c index 0f1fc1743302..4b89448cc78e 100644 --- a/fs/d_path.c +++ b/fs/d_path.c @@ -8,6 +8,8 @@ #include <linux/prefetch.h> #include "mount.h" +#include "internal.h" + static int prepend(char **buffer, int *buflen, const char *str, int namelen) { *buflen -= namelen; diff --git a/fs/internal.h b/fs/internal.h index 10517ece4516..2def264272f4 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -164,7 +164,7 @@ extern int d_set_mounted(struct dentry *dentry); extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc); extern struct dentry *d_alloc_cursor(struct dentry *); extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); -extern char *simple_dname(struct dentry *, char *, int); +char *simple_dname(struct dentry *d, char *buf, int len); extern void dput_to_list(struct dentry *, struct list_head *); extern void shrink_dentry_list(struct list_head *);