From b8798636798ee04feb0f1bb87eec0027e3f68d98 Mon Sep 17 00:00:00 2001 From: Andrzej Pietrasiewicz Date: Tue, 15 Oct 2013 08:33:13 +0200 Subject: [PATCH] usb: gadget: storage_common: pass filesem to fsg_store_cdrom If cdrom flag is set ro flag is implied. Try setting the ro first, and only if it succeeds set the cdrom flag. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Kyungmin Park Acked-by: Michal Nazarewicz Signed-off-by: Felipe Balbi --- drivers/usb/gadget/f_mass_storage.c | 7 ++++- drivers/usb/gadget/storage_common.c | 42 +++++++++++++++++++++-------- drivers/usb/gadget/storage_common.h | 3 ++- 3 files changed, 39 insertions(+), 13 deletions(-) diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c index 6e5a6daf1a12..6b5f45144cdf 100644 --- a/drivers/usb/gadget/f_mass_storage.c +++ b/drivers/usb/gadget/f_mass_storage.c @@ -3281,7 +3281,12 @@ static ssize_t fsg_lun_opts_cdrom_show(struct fsg_lun_opts *opts, char *page) static ssize_t fsg_lun_opts_cdrom_store(struct fsg_lun_opts *opts, const char *page, size_t len) { - return fsg_store_cdrom(opts->lun, page, len); + struct fsg_opts *fsg_opts; + + fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent); + + return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page, + len); } static struct fsg_lun_opts_attribute fsg_lun_opts_cdrom = diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c index 8bd5f2d838db..ec20a1f50c2d 100644 --- a/drivers/usb/gadget/storage_common.c +++ b/drivers/usb/gadget/storage_common.c @@ -371,6 +371,23 @@ ssize_t fsg_show_removable(struct fsg_lun *curlun, char *buf) } EXPORT_SYMBOL(fsg_show_removable); +/* + * The caller must hold fsg->filesem for reading when calling this function. + */ +static ssize_t _fsg_store_ro(struct fsg_lun *curlun, bool ro) +{ + if (fsg_lun_is_open(curlun)) { + LDBG(curlun, "read-only status change prevented\n"); + return -EBUSY; + } + + curlun->ro = ro; + curlun->initially_ro = ro; + LDBG(curlun, "read-only status set to %d\n", curlun->ro); + + return 0; +} + ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem, const char *buf, size_t count) { @@ -386,16 +403,11 @@ ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem, * backing file is closed. */ down_read(filesem); - if (fsg_lun_is_open(curlun)) { - LDBG(curlun, "read-only status change prevented\n"); - rc = -EBUSY; - } else { - curlun->ro = ro; - curlun->initially_ro = ro; - LDBG(curlun, "read-only status set to %d\n", curlun->ro); + rc = _fsg_store_ro(curlun, ro); + if (!rc) rc = count; - } up_read(filesem); + return rc; } EXPORT_SYMBOL(fsg_store_ro); @@ -450,7 +462,8 @@ ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem, } EXPORT_SYMBOL(fsg_store_file); -ssize_t fsg_store_cdrom(struct fsg_lun *curlun, const char *buf, size_t count) +ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem, + const char *buf, size_t count) { bool cdrom; int ret; @@ -459,9 +472,16 @@ ssize_t fsg_store_cdrom(struct fsg_lun *curlun, const char *buf, size_t count) if (ret) return ret; - curlun->cdrom = cdrom; + down_read(filesem); + ret = cdrom ? _fsg_store_ro(curlun, true) : 0; - return count; + if (!ret) { + curlun->cdrom = cdrom; + ret = count; + } + up_read(filesem); + + return ret; } EXPORT_SYMBOL(fsg_store_cdrom); diff --git a/drivers/usb/gadget/storage_common.h b/drivers/usb/gadget/storage_common.h index e0f7aa69c7ed..c74c2fdbd56e 100644 --- a/drivers/usb/gadget/storage_common.h +++ b/drivers/usb/gadget/storage_common.h @@ -221,7 +221,8 @@ ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem, ssize_t fsg_store_nofua(struct fsg_lun *curlun, const char *buf, size_t count); ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem, const char *buf, size_t count); -ssize_t fsg_store_cdrom(struct fsg_lun *curlun, const char *buf, size_t count); +ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem, + const char *buf, size_t count); ssize_t fsg_store_removable(struct fsg_lun *curlun, const char *buf, size_t count); -- 2.30.2