[PATCH 21/25] fsinfo: pstore - add sb operation fsinfo() [ver #13]
From: David Howells <dhowells@redhat.com>
Date: 2019-05-28 15:14:11
Also in:
linux-fsdevel, lkml
Subsystem:
filesystems (vfs and infrastructure), pstore filesystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Kees Cook, Linus Torvalds
From: Ian Kent <raven@themaw.net> The new fsinfo() system call adds a new super block operation ->fsinfo() which is used by file systems to provide file system specific information for fsinfo() requests. The fsinfo() request FSINFO_ATTR_PARAMETERS provides the same function as sb operation ->show_options() so it needs to be implemented by any file system that provides ->show_options() as a minimum. Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: David Howells <dhowells@redhat.com> --- fs/pstore/inode.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 4640debf8755..44f4ffc4436e 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c@@ -36,6 +36,7 @@ #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/uaccess.h> +#include <linux/fsinfo.h> #include "internal.h"
@@ -281,6 +282,33 @@ static int pstore_show_options(struct seq_file *m, struct dentry *root) return 0; } +#ifdef CONFIG_FSINFO +/* + * Get filesystem information. + */ +static int pstore_fsinfo(struct path *path, struct fsinfo_kparams *params) +{ + struct fsinfo_capabilities *caps; + + switch (params->request) { + case FSINFO_ATTR_CAPABILITIES: + caps = params->buffer; + fsinfo_set_cap(caps, FSINFO_CAP_IS_FLASH_FS); + fsinfo_set_cap(caps, FSINFO_CAP_HAS_CTIME); + fsinfo_set_cap(caps, FSINFO_CAP_HAS_MTIME); + return sizeof(*caps); + + case FSINFO_ATTR_PARAMETERS: + if (kmsg_bytes != PSTORE_DEFAULT_KMSG_BYTES) + fsinfo_note_paramf(params, "kmsg_bytes", "%lu", kmsg_bytes); + return params->usage; + + default: + return generic_fsinfo(path, params); + } +} +#endif /* CONFIG_FSINFO */ + static int pstore_reconfigure(struct fs_context *fc) { sync_filesystem(fc->root->d_sb);
@@ -293,6 +321,9 @@ static const struct super_operations pstore_ops = { .drop_inode = generic_delete_inode, .evict_inode = pstore_evict_inode, .show_options = pstore_show_options, +#ifdef CONFIG_FSINFO + .fsinfo = pstore_fsinfo, +#endif }; static struct super_block *pstore_sb;