| Message ID | 20240401082655.31613-2-d.bogdanov@yadro.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | configfs: reduce memory consumption by symlinks | expand |
On Mon, Apr 01, 2024 at 11:26:54AM +0300, Dmitry Bogdanov wrote: > Instead of preallocating PAGE_SIZE for a symlink path, allocate the exact > size of that path. > > Fixes: e9c03af21cc7 (configfs: calculate the symlink target only once) > Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com> Reviewed-by: Joel Becker <jlbec@evilplan.org> > > --- > I treat this as bugfux due to reducing of enourmous memory consumption. > --- > fs/configfs/symlink.c | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c > index 0623c3edcfb9..224c9e4899d4 100644 > --- a/fs/configfs/symlink.c > +++ b/fs/configfs/symlink.c > @@ -54,7 +54,7 @@ static void fill_item_path(struct config_item * item, char * buffer, int length) > } > > static int configfs_get_target_path(struct config_item *item, > - struct config_item *target, char *path) > + struct config_item *target, char **path) > { > int depth, size; > char *s; > @@ -66,11 +66,16 @@ static int configfs_get_target_path(struct config_item *item, > > pr_debug("%s: depth = %d, size = %d\n", __func__, depth, size); > > - for (s = path; depth--; s += 3) > + *path = kzalloc(size, GFP_KERNEL); > + if (!*path) > + return -ENOMEM; > + > + > + for (s = *path; depth--; s += 3) > strcpy(s,"../"); > > - fill_item_path(target, path, size); > - pr_debug("%s: path = '%s'\n", __func__, path); > + fill_item_path(target, *path, size); > + pr_debug("%s: path = '%s'\n", __func__, *path); > return 0; > } > > @@ -79,27 +84,22 @@ static int create_link(struct config_item *parent_item, > struct dentry *dentry) > { > struct configfs_dirent *target_sd = item->ci_dentry->d_fsdata; > - char *body; > + char *body = NULL; > int ret; > > if (!configfs_dirent_is_ready(target_sd)) > return -ENOENT; > > - body = kzalloc(PAGE_SIZE, GFP_KERNEL); > - if (!body) > - return -ENOMEM; > - > configfs_get(target_sd); > spin_lock(&configfs_dirent_lock); > if (target_sd->s_type & CONFIGFS_USET_DROPPING) { > spin_unlock(&configfs_dirent_lock); > configfs_put(target_sd); > - kfree(body); > return -ENOENT; > } > target_sd->s_links++; > spin_unlock(&configfs_dirent_lock); > - ret = configfs_get_target_path(parent_item, item, body); > + ret = configfs_get_target_path(parent_item, item, &body); > if (!ret) > ret = configfs_create_link(target_sd, parent_item->ci_dentry, > dentry, body); > -- > 2.25.1 >
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c index 0623c3edcfb9..224c9e4899d4 100644 --- a/fs/configfs/symlink.c +++ b/fs/configfs/symlink.c @@ -54,7 +54,7 @@ static void fill_item_path(struct config_item * item, char * buffer, int length) } static int configfs_get_target_path(struct config_item *item, - struct config_item *target, char *path) + struct config_item *target, char **path) { int depth, size; char *s; @@ -66,11 +66,16 @@ static int configfs_get_target_path(struct config_item *item, pr_debug("%s: depth = %d, size = %d\n", __func__, depth, size); - for (s = path; depth--; s += 3) + *path = kzalloc(size, GFP_KERNEL); + if (!*path) + return -ENOMEM; + + + for (s = *path; depth--; s += 3) strcpy(s,"../"); - fill_item_path(target, path, size); - pr_debug("%s: path = '%s'\n", __func__, path); + fill_item_path(target, *path, size); + pr_debug("%s: path = '%s'\n", __func__, *path); return 0; } @@ -79,27 +84,22 @@ static int create_link(struct config_item *parent_item, struct dentry *dentry) { struct configfs_dirent *target_sd = item->ci_dentry->d_fsdata; - char *body; + char *body = NULL; int ret; if (!configfs_dirent_is_ready(target_sd)) return -ENOENT; - body = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!body) - return -ENOMEM; - configfs_get(target_sd); spin_lock(&configfs_dirent_lock); if (target_sd->s_type & CONFIGFS_USET_DROPPING) { spin_unlock(&configfs_dirent_lock); configfs_put(target_sd); - kfree(body); return -ENOENT; } target_sd->s_links++; spin_unlock(&configfs_dirent_lock); - ret = configfs_get_target_path(parent_item, item, body); + ret = configfs_get_target_path(parent_item, item, &body); if (!ret) ret = configfs_create_link(target_sd, parent_item->ci_dentry, dentry, body);
Instead of preallocating PAGE_SIZE for a symlink path, allocate the exact size of that path. Fixes: e9c03af21cc7 (configfs: calculate the symlink target only once) Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com> --- I treat this as bugfux due to reducing of enourmous memory consumption. --- fs/configfs/symlink.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)