From: Karel Zak Date: Tue, 17 Jul 2012 19:57:22 +0000 (+0200) Subject: libmount: allow to disable swap between source and target X-Git-Tag: v2.22-rc1~125 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e39cbb76033e689093da42453839afa9c8d4c8e5;p=thirdparty%2Futil-linux.git libmount: allow to disable swap between source and target In some cases (for example if only one mount argument is given) may be mount request ambivalent: # mount /foo and fstab: /dev/sda5 /foo rw 0 0 /foo /bar bind 0 0 The libmount allows to swap between source and target (if source is not LABEL or UUID) by default. The new function mnt_context_disable_swapmatch() allows to disable this feature. Signed-off-by: Karel Zak --- diff --git a/libmount/docs/libmount-sections.txt b/libmount/docs/libmount-sections.txt index e9a6dce720..dc6aeabf5d 100644 --- a/libmount/docs/libmount-sections.txt +++ b/libmount/docs/libmount-sections.txt @@ -24,6 +24,7 @@ mnt_context_apply_fstab mnt_context_disable_canonicalize mnt_context_disable_helpers mnt_context_disable_mtab +mnt_context_disable_swapmatch mnt_context_enable_fake mnt_context_enable_force mnt_context_enable_fork @@ -32,7 +33,6 @@ mnt_context_enable_loopdel mnt_context_enable_rdonly_umount mnt_context_enable_sloppy mnt_context_enable_verbose -mnt_context_tab_applied mnt_context_get_cache mnt_context_get_fs mnt_context_get_fstab @@ -66,6 +66,7 @@ mnt_context_is_parent mnt_context_is_rdonly_umount mnt_context_is_restricted mnt_context_is_sloppy +mnt_context_is_swapmatch mnt_context_is_verbose mnt_context_reset_status mnt_context_set_cache @@ -86,6 +87,7 @@ mnt_context_set_target mnt_context_set_user_mflags mnt_context_strerror mnt_context_syscall_called +mnt_context_tab_applied mnt_context_wait_for_children diff --git a/libmount/src/context.c b/libmount/src/context.c index e0b6a35f4a..bfc418cd8d 100644 --- a/libmount/src/context.c +++ b/libmount/src/context.c @@ -502,7 +502,7 @@ int mnt_context_disable_mtab(struct libmnt_context *cxt, int disable) } /** - * mnt_context_is_nomtab + * mnt_context_is_nomtab: * @cxt: mount context * * Returns: 1 if no-mtab is enabled or 0 @@ -512,6 +512,32 @@ int mnt_context_is_nomtab(struct libmnt_context *cxt) return cxt && (cxt->flags & MNT_FL_NOMTAB) ? 1 : 0; } +/** + * mnt_context_disable_swapmatch: + * @cxt: mount context + * @disable: TRUE or FALSE + * + * Disable/enable swap between source and target for mount(8) if only one path + * is specified. + * + * Returns: 0 on success, negative number in case of error. + */ +int mnt_context_disable_swapmatch(struct libmnt_context *cxt, int disable) +{ + return set_flag(cxt, MNT_FL_NOSWAPMATCH, disable); +} + +/** + * mnt_context_is_swapmatch: + * @cxt: mount context + * + * Returns: 1 if swap between source and target is allowed (default is 1) or 0. + */ +int mnt_context_is_swapmatch(struct libmnt_context *cxt) +{ + return cxt && (cxt->flags & MNT_FL_NOSWAPMATCH) ? 0 : 1; +} + /** * mnt_context_enable_force: * @cxt: mount context @@ -1617,7 +1643,7 @@ static int apply_table(struct libmnt_context *cxt, struct libmnt_table *tb, else if (tgt) fs = mnt_table_find_target(tb, tgt, direction); - if (!fs) { + if (!fs && mnt_context_is_swapmatch(cxt)) { /* swap source and target (if @src is not LABEL/UUID), * for example in * diff --git a/libmount/src/context_umount.c b/libmount/src/context_umount.c index 39d940f6c2..2c2975e7ea 100644 --- a/libmount/src/context_umount.c +++ b/libmount/src/context_umount.c @@ -64,7 +64,7 @@ static int lookup_umount_fs(struct libmnt_context *cxt) try_loopdev: fs = mnt_table_find_target(mtab, tgt, MNT_ITER_BACKWARD); - if (!fs) { + if (!fs && mnt_context_is_swapmatch(cxt)) { /* maybe the option is source rather than target (mountpoint) */ fs = mnt_table_find_source(mtab, tgt, MNT_ITER_BACKWARD); diff --git a/libmount/src/libmount.h.in b/libmount/src/libmount.h.in index 2c66871b74..326588fecc 100644 --- a/libmount/src/libmount.h.in +++ b/libmount/src/libmount.h.in @@ -428,6 +428,7 @@ extern int mnt_context_enable_force(struct libmnt_context *cxt, int enable); extern int mnt_context_enable_verbose(struct libmnt_context *cxt, int enable); extern int mnt_context_enable_loopdel(struct libmnt_context *cxt, int enable); extern int mnt_context_enable_fork(struct libmnt_context *cxt, int enable); +extern int mnt_context_disable_swapmatch(struct libmnt_context *cxt, int disable); extern int mnt_context_get_optsmode(struct libmnt_context *cxt); extern int mnt_context_is_lazy(struct libmnt_context *cxt); @@ -440,6 +441,7 @@ extern int mnt_context_is_verbose(struct libmnt_context *cxt); extern int mnt_context_is_loopdel(struct libmnt_context *cxt); extern int mnt_context_is_nohelpers(struct libmnt_context *cxt); extern int mnt_context_is_nocanonicalize(struct libmnt_context *cxt); +extern int mnt_context_is_swapmatch(struct libmnt_context *cxt); extern int mnt_context_is_fork(struct libmnt_context *cxt); extern int mnt_context_is_parent(struct libmnt_context *cxt); diff --git a/libmount/src/libmount.sym b/libmount/src/libmount.sym index 39f81d665b..260642d4d7 100644 --- a/libmount/src/libmount.sym +++ b/libmount/src/libmount.sym @@ -244,4 +244,6 @@ global: mnt_fs_get_swaptype; mnt_fs_get_tid; mnt_fs_get_usedsize; + mnt_context_is_swapmatch; + mnt_context_disable_swapmatch; } MOUNT_2.21; diff --git a/libmount/src/mountP.h b/libmount/src/mountP.h index a2922c2b3e..0ef073a69a 100644 --- a/libmount/src/mountP.h +++ b/libmount/src/mountP.h @@ -335,6 +335,7 @@ struct libmnt_context #define MNT_FL_NOCANONICALIZE (1 << 9) #define MNT_FL_RDONLY_UMOUNT (1 << 11) /* remount,ro after EBUSY umount(2) */ #define MNT_FL_FORK (1 << 12) +#define MNT_FL_NOSWAPMATCH (1 << 13) #define MNT_FL_EXTERN_FS (1 << 15) /* cxt->fs is not private */ #define MNT_FL_EXTERN_FSTAB (1 << 16) /* cxt->fstab is not private */