diff options
Diffstat (limited to 'fs/xattr.c')
| -rw-r--r-- | fs/xattr.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/fs/xattr.c b/fs/xattr.c index ba37a8f5cfd1..2d607542281b 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -1040,6 +1040,26 @@ const char *xattr_full_name(const struct xattr_handler *handler, EXPORT_SYMBOL(xattr_full_name); /** + * simple_xattr_space - estimate the memory used by a simple xattr + * @name: the full name of the xattr + * @size: the size of its value + * + * This takes no account of how much larger the two slab objects actually are: + * that would depend on the slab implementation, when what is required is a + * deterministic number, which grows with name length and size and quantity. + * + * Return: The approximate number of bytes of memory used by such an xattr. + */ +size_t simple_xattr_space(const char *name, size_t size) +{ + /* + * Use "40" instead of sizeof(struct simple_xattr), to return the + * same result on 32-bit and 64-bit, and even if simple_xattr grows. + */ + return 40 + size + strlen(name); +} + +/** * simple_xattr_free - free an xattr object * @xattr: the xattr object * @@ -1363,14 +1383,17 @@ void simple_xattrs_init(struct simple_xattrs *xattrs) /** * simple_xattrs_free - free xattrs * @xattrs: xattr header whose xattrs to destroy + * @freed_space: approximate number of bytes of memory freed from @xattrs * * Destroy all xattrs in @xattr. When this is called no one can hold a * reference to any of the xattrs anymore. */ -void simple_xattrs_free(struct simple_xattrs *xattrs) +void simple_xattrs_free(struct simple_xattrs *xattrs, size_t *freed_space) { struct rb_node *rbp; + if (freed_space) + *freed_space = 0; rbp = rb_first(&xattrs->rb_root); while (rbp) { struct simple_xattr *xattr; @@ -1379,6 +1402,9 @@ void simple_xattrs_free(struct simple_xattrs *xattrs) rbp_next = rb_next(rbp); xattr = rb_entry(rbp, struct simple_xattr, rb_node); rb_erase(&xattr->rb_node, &xattrs->rb_root); + if (freed_space) + *freed_space += simple_xattr_space(xattr->name, + xattr->size); simple_xattr_free(xattr); rbp = rbp_next; } |