linux-block.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
	linux-block@vger.kernel.org
Subject: [PATCH 8/9] loop: split loop_lookup
Date: Wed, 23 Jun 2021 16:59:07 +0200	[thread overview]
Message-ID: <20210623145908.92973-9-hch@lst.de> (raw)
In-Reply-To: <20210623145908.92973-1-hch@lst.de>

loop_lookup has two callers - one wants to do the a find by index and the
other wants any unbound loop device.  Open code the respective
functionality in each caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/loop.c | 57 ++++++++++----------------------------------
 1 file changed, 12 insertions(+), 45 deletions(-)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 58fc29f1b1ae..93abf6d8b88c 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2184,44 +2184,6 @@ static void loop_remove(struct loop_device *lo)
 	kfree(lo);
 }
 
-static int find_free_cb(int id, void *ptr, void *data)
-{
-	struct loop_device *lo = ptr;
-	struct loop_device **l = data;
-
-	if (lo->lo_state == Lo_unbound) {
-		*l = lo;
-		return 1;
-	}
-	return 0;
-}
-
-static int loop_lookup(struct loop_device **l, int i)
-{
-	struct loop_device *lo;
-	int ret = -ENODEV;
-
-	if (i < 0) {
-		int err;
-
-		err = idr_for_each(&loop_index_idr, &find_free_cb, &lo);
-		if (err == 1) {
-			*l = lo;
-			ret = lo->lo_number;
-		}
-		goto out;
-	}
-
-	/* lookup and return a specific i */
-	lo = idr_find(&loop_index_idr, i);
-	if (lo) {
-		*l = lo;
-		ret = lo->lo_number;
-	}
-out:
-	return ret;
-}
-
 static void loop_probe(dev_t dev)
 {
 	int idx = MINOR(dev) >> part_shift;
@@ -2245,9 +2207,11 @@ static int loop_control_remove(int idx)
 	if (ret)
 		return ret;
 
-	ret = loop_lookup(&lo, idx);
-	if (ret < 0)
+	lo = idr_find(&loop_index_idr, idx);
+	if (!lo) {
+		ret = -ENODEV;
 		goto out_unlock_ctrl;
+	}
 
 	ret = mutex_lock_killable(&lo->lo_mutex);
 	if (ret)
@@ -2271,17 +2235,20 @@ static int loop_control_remove(int idx)
 static int loop_control_get_free(int idx)
 {
 	struct loop_device *lo;
-	int ret;
+	int id, ret;
 
 	ret = mutex_lock_killable(&loop_ctl_mutex);
 	if (ret)
 		return ret;
-	ret = loop_lookup(&lo, -1);
+	idr_for_each_entry(&loop_index_idr, lo, id) {
+		if (lo->lo_state == Lo_unbound)
+			goto found;
+	}
 	mutex_unlock(&loop_ctl_mutex);
-
-	if (ret >= 0)
-		return ret;
 	return loop_add(-1);
+found:
+	mutex_unlock(&loop_ctl_mutex);
+	return id;
 }
 
 static long loop_control_ioctl(struct file *file, unsigned int cmd,
-- 
2.30.2


  parent reply	other threads:[~2021-06-23 15:04 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-23 14:58 loop cleanups v2 Christoph Hellwig
2021-06-23 14:59 ` [PATCH 1/9] loop: reorder loop_exit Christoph Hellwig
2021-06-23 14:59 ` [PATCH 2/9] loop: reduce loop_ctl_mutex coverage in loop_exit Christoph Hellwig
2021-06-23 14:59 ` [PATCH 3/9] loop: remove the l argument to loop_add Christoph Hellwig
2021-06-23 14:59 ` [PATCH 4/9] loop: don't call loop_lookup before adding a loop device Christoph Hellwig
2021-06-23 14:59 ` [PATCH 5/9] loop: split loop_control_ioctl Christoph Hellwig
2021-06-23 14:59 ` [PATCH 6/9] loop: move loop_ctl_mutex locking into loop_add Christoph Hellwig
2021-06-23 14:59 ` [PATCH 7/9] loop: don't allow deleting an unspecified loop device Christoph Hellwig
2021-06-23 14:59 ` Christoph Hellwig [this message]
2021-06-23 14:59 ` [PATCH 9/9] loop: rewrite loop_exit using idr_for_each_entry Christoph Hellwig
2021-06-24  2:45 ` loop cleanups v2 Jens Axboe
  -- strict thread matches above, loose matches on Subject: below --
2021-06-21 10:15 loop cleanups Christoph Hellwig
2021-06-21 10:15 ` [PATCH 8/9] loop: split loop_lookup Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210623145908.92973-9-hch@lst.de \
    --to=hch@lst.de \
    --cc=axboe@kernel.dk \
    --cc=linux-block@vger.kernel.org \
    --cc=penguin-kernel@i-love.sakura.ne.jp \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).