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Fri, 18 Oct 2019 06:05:16 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id CCDC2B603; Fri, 18 Oct 2019 10:05:11 +0000 (UTC) Subject: Re: [PATCH v5 05/23] sg: bitops in sg_device To: Douglas Gilbert , linux-scsi@vger.kernel.org Cc: martin.petersen@oracle.com, jejb@linux.vnet.ibm.com References: <20191008075022.30055-1-dgilbert@interlog.com> <20191008075022.30055-6-dgilbert@interlog.com> From: Hannes Reinecke Openpgp: preference=signencrypt Autocrypt: addr=hare@suse.de; prefer-encrypt=mutual; keydata= mQINBE6KyREBEACwRN6XKClPtxPiABx5GW+Yr1snfhjzExxkTYaINHsWHlsLg13kiemsS6o7 qrc+XP8FmhcnCOts9e2jxZxtmpB652lxRB9jZE40mcSLvYLM7S6aH0WXKn8bOqpqOGJiY2bc 6qz6rJuqkOx3YNuUgiAxjuoYauEl8dg4bzex3KGkGRuxzRlC8APjHlwmsr+ETxOLBfUoRNuE b4nUtaseMPkNDwM4L9+n9cxpGbdwX0XwKFhlQMbG3rWA3YqQYWj1erKIPpgpfM64hwsdk9zZ QO1krgfULH4poPQFpl2+yVeEMXtsSou915jn/51rBelXeLq+cjuK5+B/JZUXPnNDoxOG3j3V VSZxkxLJ8RO1YamqZZbVP6jhDQ/bLcAI3EfjVbxhw9KWrh8MxTcmyJPn3QMMEp3wpVX9nSOQ tzG72Up/Py67VQe0x8fqmu7R4MmddSbyqgHrab/Nu+ak6g2RRn3QHXAQ7PQUq55BDtj85hd9 W2iBiROhkZ/R+Q14cJkWhzaThN1sZ1zsfBNW0Im8OVn/J8bQUaS0a/NhpXJWv6J1ttkX3S0c QUratRfX4D1viAwNgoS0Joq7xIQD+CfJTax7pPn9rT////hSqJYUoMXkEz5IcO+hptCH1HF3 qz77aA5njEBQrDRlslUBkCZ5P+QvZgJDy0C3xRGdg6ZVXEXJOQARAQABtCpIYW5uZXMgUmVp bmVja2UgKFN1U0UgTGFicykgPGhhcmVAc3VzZS5kZT6JAkEEEwECACsCGwMFCRLMAwAGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheABQJOisquAhkBAAoJEGz4yi9OyKjPOHoQAJLeLvr6JNHx GPcHXaJLHQiinz2QP0/wtsT8+hE26dLzxb7hgxLafj9XlAXOG3FhGd+ySlQ5wSbbjdxNjgsq FIjqQ88/Lk1NfnqG5aUTPmhEF+PzkPogEV7Pm5Q17ap22VK623MPaltEba+ly6/pGOODbKBH ak3gqa7Gro5YCQzNU0QVtMpWyeGF7xQK76DY/atvAtuVPBJHER+RPIF7iv5J3/GFIfdrM+wS BubFVDOibgM7UBnpa7aohZ9RgPkzJpzECsbmbttxYaiv8+EOwark4VjvOne8dRaj50qeyJH6 HLpBXZDJH5ZcYJPMgunghSqghgfuUsd5fHmjFr3hDb5EoqAfgiRMSDom7wLZ9TGtT6viDldv hfWaIOD5UhpNYxfNgH6Y102gtMmN4o2P6g3UbZK1diH13s9DA5vI2mO2krGz2c5BOBmcctE5 iS+JWiCizOqia5Op+B/tUNye/YIXSC4oMR++Fgt30OEafB8twxydMAE3HmY+foawCpGq06yM vAguLzvm7f6wAPesDAO9vxRNC5y7JeN4Kytl561ciTICmBR80Pdgs/Obj2DwM6dvHquQbQrU Op4XtD3eGUW4qgD99DrMXqCcSXX/uay9kOG+fQBfK39jkPKZEuEV2QdpE4Pry36SUGfohSNq xXW+bMc6P+irTT39VWFUJMcSuQINBE6KyREBEACvEJggkGC42huFAqJcOcLqnjK83t4TVwEn JRisbY/VdeZIHTGtcGLqsALDzk+bEAcZapguzfp7cySzvuR6Hyq7hKEjEHAZmI/3IDc9nbdh EgdCiFatah0XZ/p4vp7KAelYqbv8YF/ORLylAdLh9rzLR6yHFqVaR4WL4pl4kEWwFhNSHLxe 55G56/dxBuoj4RrFoX3ynerXfbp4dH2KArPc0NfoamqebuGNfEQmDbtnCGE5zKcR0zvmXsRp qU7+caufueZyLwjTU+y5p34U4PlOO2Q7/bdaPEdXfpgvSpWk1o3H36LvkPV/PGGDCLzaNn04 BdiiiPEHwoIjCXOAcR+4+eqM4TSwVpTn6SNgbHLjAhCwCDyggK+3qEGJph+WNtNU7uFfscSP k4jqlxc8P+hn9IqaMWaeX9nBEaiKffR7OKjMdtFFnBRSXiW/kOKuuRdeDjL5gWJjY+IpdafP KhjvUFtfSwGdrDUh3SvB5knSixE3qbxbhbNxmqDVzyzMwunFANujyyVizS31DnWC6tKzANkC k15CyeFC6sFFu+WpRxvC6fzQTLI5CRGAB6FAxz8Hu5rpNNZHsbYs9Vfr/BJuSUfRI/12eOCL IvxRPpmMOlcI4WDW3EDkzqNAXn5Onx/b0rFGFpM4GmSPriEJdBb4M4pSD6fN6Y/Jrng/Bdwk SQARAQABiQIlBBgBAgAPBQJOiskRAhsMBQkSzAMAAAoJEGz4yi9OyKjPgEwQAIP/gy/Xqc1q OpzfFScswk3CEoZWSqHxn/fZasa4IzkwhTUmukuIvRew+BzwvrTxhHcz9qQ8hX7iDPTZBcUt ovWPxz+3XfbGqE+q0JunlIsP4N+K/I10nyoGdoFpMFMfDnAiMUiUatHRf9Wsif/nT6oRiPNJ T0EbbeSyIYe+ZOMFfZBVGPqBCbe8YMI+JiZeez8L9JtegxQ6O3EMQ//1eoPJ5mv5lWXLFQfx f4rAcKseM8DE6xs1+1AIsSIG6H+EE3tVm+GdCkBaVAZo2VMVapx9k8RMSlW7vlGEQsHtI0FT c1XNOCGjaP4ITYUiOpfkh+N0nUZVRTxWnJqVPGZ2Nt7xCk7eoJWTSMWmodFlsKSgfblXVfdM 9qoNScM3u0b9iYYuw/ijZ7VtYXFuQdh0XMM/V6zFrLnnhNmg0pnK6hO1LUgZlrxHwLZk5X8F uD/0MCbPmsYUMHPuJd5dSLUFTlejVXIbKTSAMd0tDSP5Ms8Ds84z5eHreiy1ijatqRFWFJRp ZtWlhGRERnDH17PUXDglsOA08HCls0PHx8itYsjYCAyETlxlLApXWdVl9YVwbQpQ+i693t/Y PGu8jotn0++P19d3JwXW8t6TVvBIQ1dRZHx1IxGLMn+CkDJMOmHAUMWTAXX2rf5tUjas8/v2 azzYF4VRJsdl+d0MCaSy8mUh Message-ID: <49e72e62-1ce6-1588-481d-469d382dce59@suse.de> Date: Fri, 18 Oct 2019 12:05:11 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20191008075022.30055-6-dgilbert@interlog.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 10/8/19 9:50 AM, Douglas Gilbert wrote: > Introduce bitops in sg_device to replace an atomic, a bool and a > char. That char (sgdebug) had been reduced to only two states. > Add some associated macros to make the code a little clearer. > > Signed-off-by: Douglas Gilbert > --- > drivers/scsi/sg.c | 104 +++++++++++++++++++++++----------------------- > 1 file changed, 53 insertions(+), 51 deletions(-) > > diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c > index 9aa1b1030033..97ce84f0c51b 100644 > --- a/drivers/scsi/sg.c > +++ b/drivers/scsi/sg.c > @@ -74,6 +74,11 @@ static char *sg_version_date = "20190606"; > > #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) > > +/* Bit positions (flags) for sg_device::fdev_bm bitmask follow */ > +#define SG_FDEV_EXCLUDE 0 /* have fd open with O_EXCL */ > +#define SG_FDEV_DETACHING 1 /* may be unexpected device removal */ > +#define SG_FDEV_LOG_SENSE 2 /* set by ioctl(SG_SET_DEBUG) */ > + > int sg_big_buff = SG_DEF_RESERVED_SIZE; > /* N.B. This variable is readable and writeable via > /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer > @@ -155,14 +160,12 @@ struct sg_device { /* holds the state of each scsi generic device */ > struct scsi_device *device; > wait_queue_head_t open_wait; /* queue open() when O_EXCL present */ > struct mutex open_rel_lock; /* held when in open() or release() */ > - int sg_tablesize; /* adapter's max scatter-gather table size */ > - u32 index; /* device index number */ > struct list_head sfds; > rwlock_t sfd_lock; /* protect access to sfd list */ > - atomic_t detaching; /* 0->device usable, 1->device detaching */ > - bool exclude; /* 1->open(O_EXCL) succeeded and is active */ > + int sg_tablesize; /* adapter's max scatter-gather table size */ > + u32 index; /* device index number */ > int open_cnt; /* count of opens (perhaps < num(sfds) ) */ > - char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */ > + unsigned long fdev_bm[1]; /* see SG_FDEV_* defines above */ > struct gendisk *disk; > struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg] */ > struct kref d_ref; > @@ -200,6 +203,9 @@ static void sg_device_destroy(struct kref *kref); > #define SZ_SG_IO_HDR ((int)sizeof(struct sg_io_hdr)) /* v3 header */ > #define SZ_SG_REQ_INFO ((int)sizeof(struct sg_req_info)) > > +#define SG_IS_DETACHING(sdp) test_bit(SG_FDEV_DETACHING, (sdp)->fdev_bm) > +#define SG_HAVE_EXCLUDE(sdp) test_bit(SG_FDEV_EXCLUDE, (sdp)->fdev_bm) > + > /* > * Kernel needs to be built with CONFIG_SCSI_LOGGING to see log messages. > * 'depth' is a number between 1 (most severe) and 7 (most noisy, most > @@ -273,26 +279,26 @@ sg_wait_open_event(struct sg_device *sdp, bool o_excl) > while (sdp->open_cnt > 0) { > mutex_unlock(&sdp->open_rel_lock); > retval = wait_event_interruptible(sdp->open_wait, > - (atomic_read(&sdp->detaching) || > + (SG_IS_DETACHING(sdp) || > !sdp->open_cnt)); > mutex_lock(&sdp->open_rel_lock); > > if (retval) /* -ERESTARTSYS */ > return retval; > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > } > } else { > - while (sdp->exclude) { > + while (SG_HAVE_EXCLUDE(sdp)) { > mutex_unlock(&sdp->open_rel_lock); > retval = wait_event_interruptible(sdp->open_wait, > - (atomic_read(&sdp->detaching) || > - !sdp->exclude)); > + (SG_IS_DETACHING(sdp) || > + !SG_HAVE_EXCLUDE(sdp))); > mutex_lock(&sdp->open_rel_lock); > > if (retval) /* -ERESTARTSYS */ > return retval; > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > } > } > @@ -354,7 +360,7 @@ sg_open(struct inode *inode, struct file *filp) > goto error_mutex_locked; > } > } else { > - if (sdp->exclude) { > + if (SG_HAVE_EXCLUDE(sdp)) { > retval = -EBUSY; > goto error_mutex_locked; > } > @@ -367,10 +373,10 @@ sg_open(struct inode *inode, struct file *filp) > > /* N.B. at this point we are holding the open_rel_lock */ > if (o_excl) > - sdp->exclude = true; > + set_bit(SG_FDEV_EXCLUDE, sdp->fdev_bm); > > if (sdp->open_cnt < 1) { /* no existing opens */ > - sdp->sgdebug = 0; > + clear_bit(SG_FDEV_LOG_SENSE, sdp->fdev_bm); > q = sdp->device->request_queue; > sdp->sg_tablesize = queue_max_segments(q); > } > @@ -393,8 +399,8 @@ sg_open(struct inode *inode, struct file *filp) > return retval; > > out_undo: > - if (o_excl) { > - sdp->exclude = false; /* undo if error */ > + if (o_excl) { /* undo if error */ > + clear_bit(SG_FDEV_EXCLUDE, sdp->fdev_bm); > wake_up_interruptible(&sdp->open_wait); > } > error_mutex_locked: > @@ -428,12 +434,10 @@ sg_release(struct inode *inode, struct file *filp) > > /* possibly many open()s waiting on exlude clearing, start many; > * only open(O_EXCL)s wait on 0==open_cnt so only start one */ > - if (sdp->exclude) { > - sdp->exclude = false; > + if (test_and_clear_bit(SG_FDEV_EXCLUDE, sdp->fdev_bm)) > wake_up_interruptible_all(&sdp->open_wait); > - } else if (0 == sdp->open_cnt) { > + else if (sdp->open_cnt == 0) > wake_up_interruptible(&sdp->open_wait); > - } > mutex_unlock(&sdp->open_rel_lock); > return 0; > } > @@ -467,7 +471,7 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) > SG_LOG(3, sfp, "%s: write(3rd arg) count=%d\n", __func__, (int)count); > if (!sdp) > return -ENXIO; > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > if (!((filp->f_flags & O_NONBLOCK) || > scsi_block_when_processing_errors(sdp->device))) > @@ -666,7 +670,7 @@ sg_common_write(struct sg_fd *sfp, struct sg_request *srp, > sg_remove_request(sfp, srp); > return k; /* probably out of space --> ENOMEM */ > } > - if (atomic_read(&sdp->detaching)) { > + if (SG_IS_DETACHING(sdp)) { > if (srp->bio) { > scsi_req_free_cmd(scsi_req(srp->rq)); > blk_put_request(srp->rq); > @@ -831,7 +835,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) > } > srp = sg_get_rq_mark(sfp, req_pack_id); > if (!srp) { /* now wait on packet to arrive */ > - if (atomic_read(&sdp->detaching)) { > + if (SG_IS_DETACHING(sdp)) { > retval = -ENODEV; > goto free_old_hdr; > } > @@ -840,9 +844,9 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) > goto free_old_hdr; > } > retval = wait_event_interruptible(sfp->read_wait, > - (atomic_read(&sdp->detaching) || > + (SG_IS_DETACHING(sdp) || > (srp = sg_get_rq_mark(sfp, req_pack_id)))); > - if (atomic_read(&sdp->detaching)) { > + if (SG_IS_DETACHING(sdp)) { > retval = -ENODEV; > goto free_old_hdr; > } > @@ -997,7 +1001,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) > > switch (cmd_in) { > case SG_IO: > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > if (!scsi_block_when_processing_errors(sdp->device)) > return -ENXIO; > @@ -1008,8 +1012,8 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) > if (result < 0) > return result; > result = wait_event_interruptible(sfp->read_wait, > - (srp_done(sfp, srp) || atomic_read(&sdp->detaching))); > - if (atomic_read(&sdp->detaching)) > + (srp_done(sfp, srp) || SG_IS_DETACHING(sdp))); > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > write_lock_irq(&sfp->rq_list_lock); > if (srp->done) { > @@ -1052,7 +1056,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) > else { > sg_scsi_id_t __user *sg_idp = p; > > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > __put_user((int) sdp->device->host->host_no, > &sg_idp->host_no); > @@ -1176,18 +1180,18 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) > return result; > } > case SG_EMULATED_HOST: > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > return put_user(sdp->device->host->hostt->emulated, ip); > case SCSI_IOCTL_SEND_COMMAND: > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p); > case SG_SET_DEBUG: > result = get_user(val, ip); > if (result) > return result; > - sdp->sgdebug = (char) val; > + assign_bit(SG_FDEV_LOG_SENSE, sdp->fdev_bm, val); > return 0; > case BLKSECTGET: > return put_user(max_sectors_bytes(sdp->device->request_queue), > @@ -1208,7 +1212,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) > case SCSI_IOCTL_PROBE_HOST: > case SG_GET_TRANSFORM: > case SG_SCSI_RESET: > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > return -ENODEV; > break; > default: > @@ -1271,7 +1275,7 @@ sg_poll(struct file *filp, poll_table * wait) > } > read_unlock_irqrestore(&sfp->rq_list_lock, iflags); > > - if (sfp->parentdp && atomic_read(&sfp->parentdp->detaching)) { > + if (sfp->parentdp && SG_IS_DETACHING(sfp->parentdp)) { > p_res |= EPOLLHUP; > } else if (!sfp->cmd_q) { > if (count == 0) > @@ -1419,7 +1423,7 @@ sg_rq_end_io(struct request *rq, blk_status_t status) > return; > > sdp = sfp->parentdp; > - if (unlikely(atomic_read(&sdp->detaching))) > + if (unlikely(SG_IS_DETACHING(sdp))) > pr_info("%s: device detaching\n", __func__); > > sense = req->sense; > @@ -1440,9 +1444,9 @@ sg_rq_end_io(struct request *rq, blk_status_t status) > srp->header.msg_status = msg_byte(result); > srp->header.host_status = host_byte(result); > srp->header.driver_status = driver_byte(result); > - if ((sdp->sgdebug > 0) && > - ((CHECK_CONDITION == srp->header.masked_status) || > - (COMMAND_TERMINATED == srp->header.masked_status))) > + if (test_bit(SG_FDEV_LOG_SENSE, sdp->fdev_bm) && > + (srp->header.masked_status == CHECK_CONDITION || > + srp->header.masked_status == COMMAND_TERMINATED)) > __scsi_print_sense(sdp->device, __func__, sense, > SCSI_SENSE_BUFFERSIZE); > > @@ -1557,7 +1561,7 @@ sg_alloc(struct gendisk *disk, struct scsi_device *scsidp) > mutex_init(&sdp->open_rel_lock); > INIT_LIST_HEAD(&sdp->sfds); > init_waitqueue_head(&sdp->open_wait); > - atomic_set(&sdp->detaching, 0); > + clear_bit(SG_FDEV_DETACHING, sdp->fdev_bm); > rwlock_init(&sdp->sfd_lock); > sdp->sg_tablesize = queue_max_segments(q); > sdp->index = k; > @@ -1682,13 +1686,11 @@ sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) > struct sg_device *sdp = dev_get_drvdata(cl_dev); > unsigned long iflags; > struct sg_fd *sfp; > - int val; > > if (!sdp) > return; > - /* want sdp->detaching non-zero as soon as possible */ > - val = atomic_inc_return(&sdp->detaching); > - if (val > 1) > + /* set this flag as soon as possible as it could be a surprise */ > + if (test_and_set_bit(SG_FDEV_DETACHING, sdp->fdev_bm)) > return; /* only want to do following once per device */ > > SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, sdp->device, > @@ -2218,7 +2220,7 @@ sg_add_sfp(struct sg_device *sdp) > sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; > sfp->parentdp = sdp; > write_lock_irqsave(&sdp->sfd_lock, iflags); > - if (atomic_read(&sdp->detaching)) { > + if (SG_IS_DETACHING(sdp)) { > write_unlock_irqrestore(&sdp->sfd_lock, iflags); > kfree(sfp); > return ERR_PTR(-ENODEV); > @@ -2315,8 +2317,8 @@ sg_get_dev(int dev) > sdp = sg_lookup_dev(dev); > if (!sdp) > sdp = ERR_PTR(-ENXIO); > - else if (atomic_read(&sdp->detaching)) { > - /* If sdp->detaching, then the refcount may already be 0, in > + else if (SG_IS_DETACHING(sdp)) { > + /* If detaching, then the refcount may already be 0, in > * which case it would be a bug to do kref_get(). > */ > sdp = ERR_PTR(-ENODEV); > @@ -2530,8 +2532,7 @@ sg_proc_seq_show_dev(struct seq_file *s, void *v) > > read_lock_irqsave(&sg_index_lock, iflags); > sdp = it ? sg_lookup_dev(it->index) : NULL; > - if ((NULL == sdp) || (NULL == sdp->device) || > - (atomic_read(&sdp->detaching))) > + if (!sdp || !sdp->device || SG_IS_DETACHING(sdp)) > seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); > else { > scsidp = sdp->device; > @@ -2558,7 +2559,7 @@ sg_proc_seq_show_devstrs(struct seq_file *s, void *v) > read_lock_irqsave(&sg_index_lock, iflags); > sdp = it ? sg_lookup_dev(it->index) : NULL; > scsidp = sdp ? sdp->device : NULL; > - if (sdp && scsidp && (!atomic_read(&sdp->detaching))) > + if (sdp && scsidp && !SG_IS_DETACHING(sdp)) > seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", > scsidp->vendor, scsidp->model, scsidp->rev); > else > @@ -2650,7 +2651,7 @@ sg_proc_seq_show_debug(struct seq_file *s, void *v) > read_lock(&sdp->sfd_lock); > if (!list_empty(&sdp->sfds)) { > seq_printf(s, " >>> device=%s ", sdp->disk->disk_name); > - if (atomic_read(&sdp->detaching)) > + if (SG_IS_DETACHING(sdp)) > seq_puts(s, "detaching pending close "); > else if (sdp->device) { > struct scsi_device *scsidp = sdp->device; > @@ -2662,7 +2663,8 @@ sg_proc_seq_show_debug(struct seq_file *s, void *v) > scsidp->host->hostt->emulated); > } > seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", > - sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); > + sdp->sg_tablesize, SG_HAVE_EXCLUDE(sdp), > + sdp->open_cnt); > sg_proc_debug_helper(s, sdp); > } > read_unlock(&sdp->sfd_lock); > One thing to keep in mind here is that 'set_bit()' is not atomic; it needs to be followed by a memory barrier or being replaced by test_and_set_bit() if possible. Please audit the code if that poses a problem. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 247165 (AG München), GF: Felix Imendörffer