[PATCH v15 25/45] sg: replace rq array with xarray

Douglas Gilbert
2021-01-26T05:30:42Z

Remove the fixed size array of 16 request elements per file
descriptor and replace with the xarray added in the previous
patch. All sg_request objects are now kept, available for
re-use, until their owning file descriptor is closed. The
sg_request deletions are in sg_remove_sfp_usercontext().
Each active sg_request object has an associated block
request and a scsi_request object but they have different
lifetimes. The block request and the scsi_request object
are released much earlier; their lifetime is the same as it
was in the v3 sg driver. The lifetime of the bio is also the
same (but is stretched in a later patch).

Collect various flags into bit maps: one for requests
(SG_FRQ_*) and the other for file descriptors (SG_FFD_*).
They join a per sg_device bit map (SG_FDEV_*) added in an
earlier patch.

Prior to a new sg_request object being (re-)built, information
that will be placed in it uses a new struct sg_comm_wr_t
object.

Since the above changes touch almost every function and low
level structures, this patch is big.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
---
drivers/scsi/sg.c | 1560 +++++++++++++++++++++++++++++----------------
1 file changed, 997 insertions(+), 563 deletions(-)

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index e4294343dc68..69c887b379f7 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -143,36 +143,51 @@ static struct class_interface sg_interface = {
.remove_dev = sg_remove_device,
};

+/* Subset of sg_io_hdr found in <scsi/sg.h>, has only [i] and [i->o] fields */
+struct sg_slice_hdr3 {
+ int interface_id;
+ int dxfer_direction;
+ u8 cmd_len;
+ u8 mx_sb_len;
+ u16 iovec_count;
+ unsigned int dxfer_len;
+ void __user *dxferp;
+ u8 __user *cmdp;
+ void __user *sbp;
+ unsigned int timeout;
+ unsigned int flags;
+ int pack_id;
+ void __user *usr_ptr;
+};
+
struct sg_scatter_hold { /* holding area for scsi scatter gather info */
struct page **pages; /* num_sgat element array of struct page* */
int buflen; /* capacity in bytes (dlen<=buflen) */
int dlen; /* current valid data length of this req */
u16 page_order; /* byte_len = (page_size*(2**page_order)) */
u16 num_sgat; /* actual number of scatter-gather segments */
- unsigned int sglist_len; /* size of malloc'd scatter-gather list ++ */
- char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
- u8 cmd_opcode; /* first byte of command */
};

struct sg_device; /* forward declarations */
struct sg_fd;

-struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
- struct sg_scatter_hold data; /* hold buffer, perhaps scatter list */
- struct sg_io_hdr header; /* scsi command+info, see <scsi/sg.h> */
+struct sg_request { /* active SCSI command or inactive request */
+ struct sg_scatter_hold sgat_h; /* hold buffer, perhaps scatter list */
+ struct sg_slice_hdr3 s_hdr3; /* subset of sg_io_hdr */
u8 sense_b[SCSI_SENSE_BUFFERSIZE];
u32 duration; /* cmd duration in milliseconds */
+ u32 rq_flags; /* hold user supplied flags */
u32 rq_idx; /* my index within parent's srp_arr */
- char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
- char orphan; /* 1 -> drop on sight, 0 -> normal */
+ u32 rq_info; /* info supplied by v3 and v4 interfaces */
u32 rq_result; /* packed scsi request result from LLD */
- char sg_io_owned; /* 1 -> packet belongs to SG_IO */
- /* done protected by rq_list_lock */
- char done; /* 0->before bh, 1->before read, 2->read */
+ int in_resid; /* requested-actual byte count on data-in */
+ int pack_id; /* user provided packet identifier field */
+ int sense_len; /* actual sense buffer length (data-in) */
atomic_t rq_st; /* request state, holds a enum sg_rq_state */
+ u8 cmd_opcode; /* first byte of SCSI cdb */
u64 start_ns; /* starting point of command duration calc */
- unsigned long frq_bm[1]; /* see SG_FRQ_* defines above */
- struct sg_fd *parentfp; /* pointer to owning fd, even when on fl */
+ unsigned long frq_bm[1]; /* see SG_FRQ_* defines above */
+ struct sg_fd *parentfp; /* pointer to owning fd, even when on fl */
struct request *rq; /* released in sg_rq_end_io(), bio kept */
struct bio *bio; /* kept until this req -->SG_RS_INACTIVE */
struct execute_work ew_orph; /* harvest orphan request */
@@ -181,7 +196,7 @@ struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
struct sg_fd { /* holds the state of a file descriptor */
struct sg_device *parentdp; /* owning device */
wait_queue_head_t read_wait; /* queue read until command done */
- struct mutex f_mutex; /* protect against changes in this fd */
+ struct mutex f_mutex; /* serialize ioctls on this fd */
int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
u32 idx; /* my index within parent's sfp_arr */
@@ -189,15 +204,12 @@ struct sg_fd { /* holds the state of a file descriptor */
atomic_t waiting; /* number of requests awaiting receive */
atomic_t req_cnt; /* number of requests */
int sgat_elem_sz; /* initialized to scatter_elem_sz */
- struct sg_scatter_hold reserve; /* buffer for this file descriptor */
- char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
- char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
+ unsigned long ffd_bm[1]; /* see SG_FFD_* defines above */
+ pid_t tid; /* thread id when opened */
u8 next_cmd_len; /* 0: automatic, >0: use on next write() */
- char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
- char mmap_called; /* 0 -> mmap() never called on this fd */
- char res_in_use; /* 1 -> 'reserve' array in use */
- struct fasync_struct *async_qp; /* used by asynchronous notification */
- struct xarray srp_arr;
+ struct sg_request *rsv_srp;/* one reserve request per fd */
+ struct fasync_struct *async_qp; /* used by asynchronous notification */
+ struct xarray srp_arr; /* xarray of sg_request object pointers */
struct kref f_ref;
struct execute_work ew_fd; /* harvest all fd resources and lists */
};
@@ -220,8 +232,8 @@ struct sg_device { /* holds the state of each scsi generic device */

struct sg_comm_wr_t { /* arguments to sg_common_write() */
int timeout;
- int blocking;
- struct sg_request *srp;
+ unsigned long frq_bm[1]; /* see SG_FRQ_* defines above */
+ struct sg_io_hdr *h3p;
u8 *cmnd;
};

@@ -229,31 +241,32 @@ struct sg_comm_wr_t { /* arguments to sg_common_write() */
static void sg_rq_end_io(struct request *rq, blk_status_t status);
/* Declarations of other static functions used before they are defined */
static int sg_proc_init(void);
-static int sg_start_req(struct sg_request *srp, u8 *cmd);
+static int sg_start_req(struct sg_request *srp, u8 *cmd, int cmd_len,
+ int dxfer_dir);
static void sg_finish_scsi_blk_rq(struct sg_request *srp);
-static int sg_mk_sgat(struct sg_scatter_hold *schp, struct sg_fd *sfp,
- int minlen);
-static ssize_t sg_submit(struct sg_fd *sfp, struct file *filp,
- const char __user *buf, size_t count, bool blocking,
- bool read_only, bool sg_io_owned,
- struct sg_request **o_srp);
-static int sg_common_write(struct sg_fd *sfp, struct sg_comm_wr_t *cwrp);
+static int sg_mk_sgat(struct sg_request *srp, struct sg_fd *sfp, int minlen);
+static int sg_submit(struct file *filp, struct sg_fd *sfp,
+ struct sg_io_hdr *hp, bool sync,
+ struct sg_request **o_srp);
+static struct sg_request *sg_common_write(struct sg_fd *sfp,
+ struct sg_comm_wr_t *cwrp);
static int sg_read_append(struct sg_request *srp, void __user *outp,
int num_xfer);
-static void sg_remove_sgat(struct sg_fd *sfp, struct sg_scatter_hold *schp);
-static void sg_build_reserve(struct sg_fd *sfp, int req_size);
-static void sg_link_reserve(struct sg_fd *sfp, struct sg_request *srp,
- int size);
-static void sg_unlink_reserve(struct sg_fd *sfp, struct sg_request *srp);
+static void sg_remove_sgat(struct sg_request *srp);
static struct sg_fd *sg_add_sfp(struct sg_device *sdp);
static void sg_remove_sfp(struct kref *);
static struct sg_request *sg_find_srp_by_id(struct sg_fd *sfp, int pack_id);
-static struct sg_request *sg_setup_req(struct sg_fd *sfp);
+static struct sg_request *sg_setup_req(struct sg_fd *sfp, int dxfr_len,
+ struct sg_comm_wr_t *cwrp);
static void sg_deact_request(struct sg_fd *sfp, struct sg_request *srp);
static struct sg_device *sg_get_dev(int dev);
static void sg_device_destroy(struct kref *kref);
+static struct sg_request *sg_mk_srp_sgat(struct sg_fd *sfp, bool first,
+ int db_len);
static const char *sg_rq_st_str(enum sg_rq_state rq_st, bool long_str);

+#define SG_WRITE_COUNT_LIMIT (32 * 1024 * 1024)
+
#define SZ_SG_HEADER ((int)sizeof(struct sg_header)) /* v1 and v2 header */
#define SZ_SG_IO_HDR ((int)sizeof(struct sg_io_hdr)) /* v3 header */
#define SZ_SG_REQ_INFO ((int)sizeof(struct sg_req_info))
@@ -519,6 +532,7 @@ sg_release(struct inode *inode, struct file *filp)
static ssize_t
sg_write(struct file *filp, const char __user *p, size_t count, loff_t *ppos)
{
+ bool get_v3_hdr;
int mxsize, cmd_size, input_size, res;
u8 opcode;
struct sg_device *sdp;
@@ -541,36 +555,61 @@ sg_write(struct file *filp, const char __user *p, size_t count, loff_t *ppos)
res = sg_allow_if_err_recovery(sdp, !!(filp->f_flags & O_NONBLOCK));
if (res)
return res;
-
- if (count < SZ_SG_HEADER)
+ if (count < SZ_SG_HEADER || count > SG_WRITE_COUNT_LIMIT)
return -EIO;
- if (copy_from_user(ohp, p, SZ_SG_HEADER))
- return -EFAULT;
- if (ohp->reply_len < 0) { /* assume this is v3 */
- struct sg_io_hdr *reinter_2p = (struct sg_io_hdr *)ohp;
+#ifdef CONFIG_COMPAT
+ if (in_compat_syscall())
+ get_v3_hdr = (count == sizeof(struct compat_sg_io_hdr));
+ else
+ get_v3_hdr = (count == sizeof(struct sg_io_hdr));
+#else
+ get_v3_hdr = (count == sizeof(struct sg_io_hdr));
+#endif
+ if (get_v3_hdr) {
+ if (get_sg_io_hdr(h3p, p))
+ return -EFAULT;
+ } else {
+ if (copy_from_user(ohp, p, SZ_SG_HEADER))
+ return -EFAULT;
+ if (ohp->reply_len < 0) { /* not v2, may be v3 */
+ bool lt = false;

- if (count < SZ_SG_IO_HDR)
- return -EIO;
- if (reinter_2p->interface_id != 'S') {
+#ifdef CONFIG_COMPAT
+ if (in_compat_syscall())
+ lt = (count < sizeof(struct compat_sg_io_hdr));
+ else
+ lt = (count < sizeof(struct sg_io_hdr));
+#else
+ lt = (count < sizeof(struct sg_io_hdr));
+#endif
+ if (lt)
+ return -EIO;
+ get_v3_hdr = true;
+ if (get_sg_io_hdr(h3p, p))
+ return -EFAULT;
+ }
+ }
+ if (get_v3_hdr) {
+ /* v3 dxfer_direction_s are all negative values by design */
+ if (h3p->dxfer_direction >= 0) { /* so it is not v3 */
+ memcpy(ohp, h3p, count);
+ goto to_v2;
+ }
+ if (h3p->interface_id != 'S') {
pr_info_once("sg: %s: v3 interface only here\n",
__func__);
return -EPERM;
}
- return sg_submit(sfp, filp, p, count,
- !(filp->f_flags & O_NONBLOCK), false, false,
- NULL);
+ res = sg_submit(filp, sfp, h3p, false, NULL);
+ return res < 0 ? res : (int)count;
}
+to_v2:
+ /* v1 and v2 interfaces processed below this point */
if (count < (SZ_SG_HEADER + 6))
- return -EIO; /* The minimum scsi command length is 6 bytes. */
-
+ return -EIO; /* minimum scsi command length is 6 bytes */
p += SZ_SG_HEADER;
if (get_user(opcode, p))
return -EFAULT;
-
- if (!(srp = sg_setup_req(sfp))) {
- SG_LOG(1, sfp, "%s: queue full\n", __func__);
- return -EDOM;
- }
mutex_lock(&sfp->f_mutex);
if (sfp->next_cmd_len > 0) {
cmd_size = sfp->next_cmd_len;
@@ -587,12 +626,10 @@ sg_write(struct file *filp, const char __user *p, size_t count, loff_t *ppos)
mxsize = max_t(int, input_size, ohp->reply_len);
mxsize -= SZ_SG_HEADER;
input_size -= SZ_SG_HEADER;
- if (input_size < 0) {
- sg_deact_request(sfp, srp);
- return -EIO; /* User did not pass enough bytes for this command. */
- }
- h3p = &srp->header;
- h3p->interface_id = '\0'; /* indicator of old interface tunnelled */
+ if (input_size < 0)
+ return -EIO; /* Insufficient bytes passed for this command. */
+ memset(h3p, 0, sizeof(*h3p));
+ h3p->interface_id = '\0';/* indicate v1 or v2 interface (tunnelled) */
h3p->cmd_len = (u8)cmd_size;
h3p->iovec_count = 0;
h3p->mx_sb_len = 0;
@@ -613,10 +650,9 @@ sg_write(struct file *filp, const char __user *p, size_t count, loff_t *ppos)
h3p->flags = input_size; /* structure abuse ... */
h3p->pack_id = ohp->pack_id;
h3p->usr_ptr = NULL;
- if (copy_from_user(cmnd, p, cmd_size)) {
- sg_deact_request(sfp, srp);
+ cmnd[0] = opcode;
+ if (copy_from_user(cmnd + 1, p + 1, cmd_size - 1))
return -EFAULT;
- }
/*
* SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
* but it is possible that the app intended SG_DXFER_TO_DEV, because
@@ -630,23 +666,23 @@ sg_write(struct file *filp, const char __user *p, size_t count, loff_t *ppos)
__func__, ohp->reply_len - (int)SZ_SG_HEADER,
input_size, (unsigned int)cmnd[0], current->comm);
}
+ cwr.frq_bm[0] = 0; /* initial state clear for all req flags */
+ cwr.h3p = h3p;
cwr.timeout = sfp->timeout;
- cwr.blocking = !(filp->f_flags & O_NONBLOCK);
- cwr.srp = srp;
cwr.cmnd = cmnd;
- res = sg_common_write(sfp, &cwr);
- return (res < 0) ? res : count;
+ srp = sg_common_write(sfp, &cwr);
+ return (IS_ERR(srp)) ? PTR_ERR(srp) : (int)count;
}

static inline int
sg_chk_mmap(struct sg_fd *sfp, int rq_flags, int len)
{
- if (len > sfp->reserve.buflen)
- return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
+ if (!xa_empty(&sfp->srp_arr))
+ return -EBUSY; /* already active requests on fd */
+ if (len > sfp->rsv_srp->sgat_h.buflen)
+ return -ENOMEM; /* MMAP_IO size must fit in reserve */
if (rq_flags & SG_FLAG_DIRECT_IO)
- return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
- if (sfp->res_in_use)
- return -EBUSY; /* reserve buffer already being used */
+ return -EINVAL; /* not both MMAP_IO and DIRECT_IO */
return 0;
}

@@ -671,61 +707,40 @@ sg_fetch_cmnd(struct file *filp, struct sg_fd *sfp, const u8 __user *u_cdbp,
return 0;
}

-static ssize_t
-sg_submit(struct sg_fd *sfp, struct file *filp, const char __user *buf,
- size_t count, bool blocking, bool read_only, bool sg_io_owned,
- struct sg_request **o_srp)
+static int
+sg_submit(struct file *filp, struct sg_fd *sfp, struct sg_io_hdr *hp,
+ bool sync, struct sg_request **o_srp)
{
- int k, res, timeout;
+ int res, timeout;
+ unsigned long ul_timeout;
struct sg_request *srp;
- struct sg_io_hdr *hp;
struct sg_comm_wr_t cwr;
u8 cmnd[SG_MAX_CDB_SIZE];
- unsigned long ul_timeout;

- if (count < SZ_SG_IO_HDR)
- return -EINVAL;
-
- sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
- if (!(srp = sg_setup_req(sfp))) {
- SG_LOG(1, sfp, "%s: queue full\n", __func__);
- return -EDOM;
- }
- srp->sg_io_owned = sg_io_owned;
- hp = &srp->header;
- /* get_sg_io_hdr() is defined in block/scsi_ioctl.c */
- if (get_sg_io_hdr(hp, buf)) {
- sg_deact_request(sfp, srp);
- return -EFAULT;
- }
- if (hp->interface_id != 'S') {
- sg_deact_request(sfp, srp);
- return -ENOSYS;
- }
+ /* now doing v3 blocking (sync) or non-blocking submission */
if (hp->flags & SG_FLAG_MMAP_IO) {
res = sg_chk_mmap(sfp, hp->flags, hp->dxfer_len);
- if (res) {
- sg_deact_request(sfp, srp);
+ if (res)
return res;
- }
}
- ul_timeout = msecs_to_jiffies(srp->header.timeout);
- timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
+ /* when v3 seen, allow cmd_q on this fd (def: no cmd_q) */
+ set_bit(SG_FFD_CMD_Q, sfp->ffd_bm);
+ ul_timeout = msecs_to_jiffies(hp->timeout);
+ timeout = min_t(unsigned long, ul_timeout, INT_MAX);
res = sg_fetch_cmnd(filp, sfp, hp->cmdp, hp->cmd_len, cmnd);
- if (res) {
- sg_deact_request(sfp, srp);
+ if (res)
return res;
- }
+ cwr.frq_bm[0] = 0;
+ __assign_bit(SG_FRQ_SYNC_INVOC, cwr.frq_bm, (int)sync);
+ cwr.h3p = hp;
cwr.timeout = timeout;
- cwr.blocking = blocking;
- cwr.srp = srp;
cwr.cmnd = cmnd;
- k = sg_common_write(sfp, &cwr);
- if (k < 0)
- return k;
+ srp = sg_common_write(sfp, &cwr);
+ if (IS_ERR(srp))
+ return PTR_ERR(srp);
if (o_srp)
- *o_srp = cwr.srp;
- return count;
+ *o_srp = srp;
+ return 0;
}

#if IS_ENABLED(SG_LOG_ACTIVE)
@@ -843,75 +858,79 @@ sg_rq_state_chg(struct sg_request *srp, enum sg_rq_state old_st,
* sg_request object holding the request just issued or a negated errno
* value twisted by ERR_PTR.
*/
-static int
+static struct sg_request *
sg_common_write(struct sg_fd *sfp, struct sg_comm_wr_t *cwrp)
{
bool at_head;
- int k;
+ int res = 0;
+ int dxfr_len, dir, cmd_len;
+ int pack_id = SG_PACK_ID_WILDCARD;
+ u32 rq_flags;
struct sg_device *sdp = sfp->parentdp;
- struct sg_request *srp = cwrp->srp;
- struct sg_io_hdr *hp = &srp->header;
-
- srp->data.cmd_opcode = cwrp->cmnd[0]; /* hold opcode of command */
- hp->status = 0;
- hp->masked_status = 0;
- hp->msg_status = 0;
- hp->info = 0;
- hp->host_status = 0;
- hp->driver_status = 0;
- hp->resid = 0;
- SG_LOG(4, sfp, "%s: opcode=0x%02x, cmd_sz=%d\n", __func__,
- (int)cwrp->cmnd[0], hp->cmd_len);
-
- if (hp->dxfer_len >= SZ_256M) {
- sg_deact_request(sfp, srp);
- return -EINVAL;
- }
-
- k = sg_start_req(srp, cwrp->cmnd);
- if (k) {
- SG_LOG(1, sfp, "%s: start_req err=%d\n", __func__, k);
- sg_finish_scsi_blk_rq(srp);
- sg_deact_request(sfp, srp);
- return k; /* probably out of space --> ENOMEM */
+ struct sg_request *srp;
+ struct sg_io_hdr *hi_p;
+
+ hi_p = cwrp->h3p;
+ dir = hi_p->dxfer_direction;
+ dxfr_len = hi_p->dxfer_len;
+ rq_flags = hi_p->flags;
+ pack_id = hi_p->pack_id;
+ if (dxfr_len >= SZ_256M)
+ return ERR_PTR(-EINVAL);
+
+ srp = sg_setup_req(sfp, dxfr_len, cwrp);
+ if (IS_ERR(srp))
+ return srp;
+ srp->rq_flags = rq_flags;
+ srp->pack_id = pack_id;
+
+ cmd_len = hi_p->cmd_len;
+ memcpy(&srp->s_hdr3, hi_p, sizeof(srp->s_hdr3));
+ srp->cmd_opcode = cwrp->cmnd[0];/* hold opcode of command for debug */
+ SG_LOG(4, sfp, "%s: opcode=0x%02x, cdb_sz=%d, pack_id=%d\n", __func__,
+ (int)cwrp->cmnd[0], cmd_len, pack_id);
+
+ res = sg_start_req(srp, cwrp->cmnd, cmd_len, dir);
+ if (res < 0) /* probably out of space --> -ENOMEM */
+ goto err_out;
+ if (unlikely(SG_IS_DETACHING(sdp))) {
+ res = -ENODEV;
+ goto err_out;
}
- if (SG_IS_DETACHING(sdp))
+ if (unlikely(test_bit(SG_FRQ_BLK_PUT_REQ, srp->frq_bm) || !srp->rq)) {
+ res = -EIDRM; /* this failure unexpected but observed */
goto err_out;
-
- hp->duration = jiffies_to_msecs(jiffies);
- if (hp->interface_id != '\0' && /* v3 (or later) interface */
- (SG_FLAG_Q_AT_TAIL & hp->flags))
- at_head = false;
- else
- at_head = true;
-
- if (!xa_get_mark(&sfp->srp_arr, srp->rq_idx, SG_XA_RQ_FREE)) {
+ }
+ if (xa_get_mark(&sfp->srp_arr, srp->rq_idx, SG_XA_RQ_FREE)) {
SG_LOG(1, sfp, "%s: ahhh, request erased!!!\n", __func__);
+ res = -ENODEV;
goto err_out;
}
- if (!srp->sg_io_owned)
- atomic_inc(&sfp->submitted);
srp->rq->timeout = cwrp->timeout;
kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
+ res = sg_rq_state_chg(srp, SG_RS_BUSY, SG_RS_INFLIGHT, false,
+ __func__);
+ if (res)
+ goto err_out;
+ srp->start_ns = ktime_get_boottime_ns();
+ srp->duration = 0;
+
+ if (srp->s_hdr3.interface_id == '\0')
+ at_head = true; /* backward compatibility: v1+v2 interfaces */
+ else if (test_bit(SG_FFD_Q_AT_TAIL, sfp->ffd_bm))
+ /* cmd flags can override sfd setting */
+ at_head = !!(srp->rq_flags & SG_FLAG_Q_AT_HEAD);
+ else /* this sfd is defaulting to head */
+ at_head = !(srp->rq_flags & SG_FLAG_Q_AT_TAIL);
+ if (!test_bit(SG_FRQ_SYNC_INVOC, srp->frq_bm))
+ atomic_inc(&sfp->submitted);
blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
srp->rq, at_head, sg_rq_end_io);
- return 0;
+ return srp;
err_out:
- if (srp->bio) {
- scsi_req_free_cmd(scsi_req(srp->rq));
- blk_put_request(srp->rq);
- srp->rq = NULL;
- }
sg_finish_scsi_blk_rq(srp);
sg_deact_request(sfp, srp);
- return -ENODEV;
-}
-
-static inline int
-sg_rstate_chg(struct sg_request *srp, enum sg_rq_state old_st,
- enum sg_rq_state new_st)
-{
- return sg_rq_state_chg(srp, old_st, new_st, false, __func__);
+ return ERR_PTR(res);
}

/*
@@ -942,21 +961,26 @@ static int
sg_copy_sense(struct sg_request *srp)
{
int sb_len_ret = 0;
- struct sg_io_hdr *hp = &srp->header;
+ int scsi_stat;

/* If need be, copy the sense buffer to the user space */
- if ((CHECK_CONDITION & hp->masked_status) ||
- (DRIVER_SENSE & hp->driver_status)) {
- int sb_len = SCSI_SENSE_BUFFERSIZE;
- void __user *up = hp->sbp;
-
- sb_len = min_t(int, hp->mx_sb_len, sb_len);
- /* Additional sense length field */
- sb_len_ret = 8 + (int)srp->sense_b[7];
- sb_len_ret = min_t(int, sb_len_ret, sb_len);
- if (copy_to_user(up, srp->sense_b, sb_len_ret))
- return -EFAULT;
- hp->sb_len_wr = sb_len_ret;
+ scsi_stat = srp->rq_result & 0xff;
+ if ((scsi_stat & SAM_STAT_CHECK_CONDITION) ||
+ (driver_byte(srp->rq_result) & DRIVER_SENSE)) {
+ int sb_len = min_t(int, SCSI_SENSE_BUFFERSIZE, srp->sense_len);
+ int mx_sb_len = srp->s_hdr3.mx_sb_len;
+ void __user *up = srp->s_hdr3.sbp;
+
+ if (up && mx_sb_len > 0) {
+ sb_len = min_t(int, mx_sb_len, sb_len);
+ /* Additional sense length field */
+ sb_len_ret = 8 + (int)srp->sense_b[7];
+ sb_len_ret = min_t(int, sb_len_ret, sb_len);
+ if (copy_to_user(up, srp->sense_b, sb_len_ret))
+ sb_len_ret = -EFAULT;
+ } else {
+ sb_len_ret = 0;
+ }
}
return sb_len_ret;
}
@@ -965,12 +989,15 @@ static int
sg_rec_state_v3(struct sg_fd *sfp, struct sg_request *srp)
{
int sb_len_wr;
+ u32 rq_res = srp->rq_result;

sb_len_wr = sg_copy_sense(srp);
if (sb_len_wr < 0)
return sb_len_wr;
+ if (rq_res & SG_ML_RESULT_MSK)
+ srp->rq_info |= SG_INFO_CHECK;
if (unlikely(SG_IS_DETACHING(sfp->parentdp)))
- return -ENODEV;
+ srp->rq_info |= SG_INFO_DEVICE_DETACHING;
return 0;
}

@@ -978,8 +1005,10 @@ static ssize_t
sg_receive_v3(struct sg_fd *sfp, struct sg_request *srp, size_t count,
void __user *p)
{
- int err = 0;
- struct sg_io_hdr *hp = &srp->header;
+ int err, err2;
+ int rq_result = srp->rq_result;
+ struct sg_io_hdr hdr3;
+ struct sg_io_hdr *hp = &hdr3;

if (in_compat_syscall()) {
if (count < sizeof(struct compat_sg_io_hdr)) {
@@ -992,9 +1021,23 @@ sg_receive_v3(struct sg_fd *sfp, struct sg_request *srp, size_t count,
}
SG_LOG(3, sfp, "%s: srp=0x%pK\n", __func__, srp);
err = sg_rec_state_v3(sfp, srp);
- if (hp->masked_status || hp->host_status || hp->driver_status)
- hp->info |= SG_INFO_CHECK;
- err = put_sg_io_hdr(hp, p);
+ memset(hp, 0, sizeof(*hp));
+ memcpy(hp, &srp->s_hdr3, sizeof(srp->s_hdr3));
+ hp->sb_len_wr = srp->sense_len;
+ hp->info = srp->rq_info;
+ hp->resid = srp->in_resid;
+ hp->duration = srp->duration;
+ hp->status = rq_result & 0xff;
+ hp->masked_status = status_byte(rq_result);
+ hp->msg_status = msg_byte(rq_result);
+ hp->host_status = host_byte(rq_result);
+ hp->driver_status = driver_byte(rq_result);
+ err2 = put_sg_io_hdr(hp, p);
+ err = err ? err : err2;
+ err2 = sg_rq_state_chg(srp, atomic_read(&srp->rq_st), SG_RS_RCV_DONE,
+ false, __func__);
+ if (err2)
+ err = err ? err : err2;
err_out:
sg_finish_scsi_blk_rq(srp);
sg_deact_request(sfp, srp);
@@ -1011,26 +1054,27 @@ sg_read_v1v2(void __user *buf, int count, struct sg_fd *sfp,
struct sg_request *srp)
{
int res = 0;
- struct sg_io_hdr *sh3p = &srp->header;
+ u32 rq_result = srp->rq_result;
struct sg_header *h2p;
+ struct sg_slice_hdr3 *sh3p;
struct sg_header a_v2hdr;

h2p = &a_v2hdr;
memset(h2p, 0, SZ_SG_HEADER);
+ sh3p = &srp->s_hdr3;
h2p->reply_len = (int)sh3p->timeout;
h2p->pack_len = h2p->reply_len; /* old, strange behaviour */
h2p->pack_id = sh3p->pack_id;
- h2p->twelve_byte = (srp->data.cmd_opcode >= 0xc0 &&
- sh3p->cmd_len == 12);
- h2p->target_status = sh3p->masked_status;
- h2p->host_status = sh3p->host_status;
- h2p->driver_status = sh3p->driver_status;
- if ((CHECK_CONDITION & h2p->target_status) ||
- (DRIVER_SENSE & sh3p->driver_status)) {
+ h2p->twelve_byte = (srp->cmd_opcode >= 0xc0 && sh3p->cmd_len == 12);
+ h2p->target_status = status_byte(rq_result);
+ h2p->host_status = host_byte(rq_result);
+ h2p->driver_status = driver_byte(rq_result);
+ if ((CHECK_CONDITION & status_byte(rq_result)) ||
+ (DRIVER_SENSE & driver_byte(rq_result))) {
memcpy(h2p->sense_buffer, srp->sense_b,
sizeof(h2p->sense_buffer));
}
- switch (h2p->host_status) {
+ switch (host_byte(rq_result)) {
/*
* This following setting of 'result' is for backward compatibility
* and is best ignored by the user who should use target, host and
@@ -1054,7 +1098,7 @@ sg_read_v1v2(void __user *buf, int count, struct sg_fd *sfp,
h2p->result = EIO;
break;
case DID_ERROR:
- h2p->result = (h2p->target_status == GOOD) ? 0 : EIO;
+ h2p->result = (status_byte(rq_result) == GOOD) ? 0 : EIO;
break;
default:
h2p->result = EIO;
@@ -1075,6 +1119,7 @@ sg_read_v1v2(void __user *buf, int count, struct sg_fd *sfp,
} else {
res = (h2p->result == 0) ? 0 : -EIO;
}
+ atomic_set(&srp->rq_st, SG_RS_RCV_DONE);
sg_finish_scsi_blk_rq(srp);
sg_deact_request(sfp, srp);
return res;
@@ -1118,13 +1163,13 @@ sg_read(struct file *filp, char __user *p, size_t count, loff_t *ppos)
hlen = could_be_v3 ? SZ_SG_IO_HDR : SZ_SG_HEADER;
h2p = (struct sg_header *)&a_sg_io_hdr;

- if (sfp->force_packid && count >= hlen) {
+ if (test_bit(SG_FFD_FORCE_PACKID, sfp->ffd_bm) && (int)count >= hlen) {
/*
* Even though this is a user space read() system call, this
* code is cheating to fetch the pack_id.
* Only need first three 32 bit ints to determine interface.
*/
- if (unlikely(copy_from_user(h2p, p, 3 * sizeof(int))))
+ if (copy_from_user(h2p, p, 3 * sizeof(int)))
return -EFAULT;
if (h2p->reply_len < 0 && could_be_v3) {
struct sg_io_hdr *v3_hdr = (struct sg_io_hdr *)h2p;
@@ -1145,20 +1190,20 @@ sg_read(struct file *filp, char __user *p, size_t count, loff_t *ppos)
}
srp = sg_find_srp_by_id(sfp, want_id);
if (!srp) { /* nothing available so wait on packet to arrive or */
- if (SG_IS_DETACHING(sdp))
+ if (unlikely(SG_IS_DETACHING(sdp)))
return -ENODEV;
if (non_block) /* O_NONBLOCK or v3::flags & SGV4_FLAG_IMMED */
return -EAGAIN;
ret = wait_event_interruptible(sfp->read_wait,
sg_get_ready_srp(sfp, &srp,
want_id));
- if (SG_IS_DETACHING(sdp))
+ if (unlikely(SG_IS_DETACHING(sdp)))
return -ENODEV;
if (ret) /* -ERESTARTSYS as signal hit process */
return ret;
/* otherwise srp should be valid */
}
- if (srp->header.interface_id == '\0')
+ if (srp->s_hdr3.interface_id == '\0')
ret = sg_read_v1v2(p, (int)count, sfp, srp);
else
ret = sg_receive_v3(sfp, srp, count, p);
@@ -1229,7 +1274,7 @@ sg_calc_rq_dur(const struct sg_request *srp)
return (diff > (s64)U32_MAX) ? 3999999999U : (u32)diff;
}

-/* Return of U32_MAX means srp is inactive */
+/* Return of U32_MAX means srp is inactive state */
static u32
sg_get_dur(struct sg_request *srp, const enum sg_rq_state *sr_stp,
bool *is_durp)
@@ -1260,34 +1305,63 @@ static void
sg_fill_request_element(struct sg_fd *sfp, struct sg_request *srp,
struct sg_req_info *rip)
{
- unsigned int ms;
+ unsigned long iflags;

- rip->req_state = srp->done + 1;
- rip->problem = srp->header.masked_status &
- srp->header.host_status &
- srp->header.driver_status;
- rip->duration = sg_get_dur(srp, NULL, NULL); /* dummy */
- if (srp->done) {
- rip->duration = srp->header.duration;
- } else {
- ms = jiffies_to_msecs(jiffies);
- rip->duration = (ms > srp->header.duration) ?
- (ms - srp->header.duration) : 0;
- }
- rip->orphan = srp->orphan;
- rip->sg_io_owned = srp->sg_io_owned;
- rip->pack_id = srp->header.pack_id;
- rip->usr_ptr = srp->header.usr_ptr;
+ xa_lock_irqsave(&sfp->srp_arr, iflags);
+ rip->duration = sg_get_dur(srp, NULL, NULL);
+ if (rip->duration == U32_MAX)
+ rip->duration = 0;
+ rip->orphan = test_bit(SG_FRQ_IS_ORPHAN, srp->frq_bm);
+ rip->sg_io_owned = test_bit(SG_FRQ_SYNC_INVOC, srp->frq_bm);
+ rip->problem = !!(srp->rq_result & SG_ML_RESULT_MSK);
+ rip->pack_id = srp->pack_id;
+ rip->usr_ptr = srp->s_hdr3.usr_ptr;
+ xa_unlock_irqrestore(&sfp->srp_arr, iflags);
+}

+static inline bool
+sg_rq_landed(struct sg_device *sdp, struct sg_request *srp)
+{
+ return atomic_read(&srp->rq_st) != SG_RS_INFLIGHT ||
+ unlikely(SG_IS_DETACHING(sdp));
}

+/*
+ * This is a blocking wait for a specific srp. When h4p is non-NULL, it is
+ * the blocking multiple request case
+ */
static int
-srp_done(struct sg_fd *sfp, struct sg_request *srp)
+sg_wait_event_srp(struct file *filp, struct sg_fd *sfp, void __user *p,
+ struct sg_request *srp)
{
- int ret;
+ int res;
+ enum sg_rq_state sr_st;
+ struct sg_device *sdp = sfp->parentdp;

- ret = srp->done;
- return ret;
+ SG_LOG(3, sfp, "%s: about to wait_event...()\n", __func__);
+ /* usually will be woken up by sg_rq_end_io() callback */
+ res = wait_event_interruptible(sfp->read_wait,
+ sg_rq_landed(sdp, srp));
+ if (unlikely(res)) { /* -ERESTARTSYS because signal hit thread */
+ set_bit(SG_FRQ_IS_ORPHAN, srp->frq_bm);
+ /* orphans harvested when sfp->keep_orphan is false */
+ atomic_set(&srp->rq_st, SG_RS_INFLIGHT);
+ SG_LOG(1, sfp, "%s: wait_event_interruptible gave %d\n",
+ __func__, res);
+ return res;
+ }
+ if (unlikely(SG_IS_DETACHING(sdp))) {
+ atomic_set(&srp->rq_st, SG_RS_INACTIVE);
+ return -ENODEV;
+ }
+ sr_st = atomic_read(&srp->rq_st);
+ if (unlikely(sr_st != SG_RS_AWAIT_RCV))
+ return -EPROTO; /* Logic error */
+ res = sg_rq_state_chg(srp, sr_st, SG_RS_BUSY, false, __func__);
+ if (unlikely(res))
+ return res;
+ res = sg_receive_v3(sfp, srp, SZ_SG_IO_HDR, p);
+ return (res < 0) ? res : 0;
}

/*
@@ -1298,42 +1372,119 @@ static int
sg_ctl_sg_io(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
void __user *p)
{
- bool read_only = O_RDWR != (filp->f_flags & O_ACCMODE);
int res;
- struct sg_request *srp;
+ struct sg_request *srp = NULL;
+ u8 hu8arr[SZ_SG_IO_HDR];
+ struct sg_io_hdr *h3p = (struct sg_io_hdr *)hu8arr;

+ SG_LOG(3, sfp, "%s: SG_IO%s\n", __func__,
+ ((filp->f_flags & O_NONBLOCK) ? " O_NONBLOCK ignored" : ""));
res = sg_allow_if_err_recovery(sdp, false);
if (res)
return res;
- res = sg_submit(sfp, filp, p, SZ_SG_IO_HDR, true, read_only,
- true, &srp);
- if (res < 0)
+ if (get_sg_io_hdr(h3p, p))
+ return -EFAULT;
+ if (h3p->interface_id == 'S')
+ res = sg_submit(filp, sfp, h3p, true, &srp);
+ else
+ return -EPERM;
+ if (unlikely(res < 0))
+ return res;
+ if (!srp) /* mrq case: already processed all responses */
return res;
- res = wait_event_interruptible
- (sfp->read_wait, (srp_done(sfp, srp) || SG_IS_DETACHING(sdp)));
- if (SG_IS_DETACHING(sdp))
- return -ENODEV;
- if (srp->done) {
- srp->done = 2;
- res = sg_receive_v3(sfp, srp, SZ_SG_IO_HDR, p);
- return (res < 0) ? res : 0;
- }
- srp->orphan = 1;
+ res = sg_wait_event_srp(filp, sfp, p, srp);
+ if (res)
+ SG_LOG(1, sfp, "%s: %s=0x%pK state: %s\n", __func__,
+ "unexpected srp", srp,
+ sg_rq_st_str(atomic_read(&srp->rq_st), false));
return res;
}

+/*
+ * First normalize want_rsv_sz to be >= sfp->sgat_elem_sz and
+ * <= max_segment_size. Exit if that is the same as old size; otherwise
+ * create a new candidate request of the new size. Then decide whether to
+ * re-use an existing free list request (least buflen >= required size) or
+ * use the new candidate. If new one used, leave old one but it is no longer
+ * the reserved request. Returns 0 on success, else a negated errno value.
+ */
static int
sg_set_reserved_sz(struct sg_fd *sfp, int want_rsv_sz)
{
- if (want_rsv_sz != sfp->reserve.buflen) {
- if (sfp->mmap_called ||
- sfp->res_in_use) {
- return -EBUSY;
+ bool use_new_srp = false;
+ int res = 0;
+ int new_sz, blen;
+ unsigned long idx, iflags;
+ struct sg_request *o_srp; /* prior reserve sg_request */
+ struct sg_request *n_srp; /* new sg_request, may be used */
+ struct sg_request *t_srp; /* other fl entries */
+ struct sg_device *sdp = sfp->parentdp;
+ struct xarray *xafp = &sfp->srp_arr;
+
+ o_srp = sfp->rsv_srp;
+ if (!o_srp)
+ return -EPROTO;
+ new_sz = min_t(int, want_rsv_sz, sdp->max_sgat_sz);
+ new_sz = max_t(int, new_sz, sfp->sgat_elem_sz);
+ blen = o_srp->sgat_h.buflen;
+ SG_LOG(3, sfp, "%s: was=%d, ask=%d, new=%d (sgat_elem_sz=%d)\n",
+ __func__, blen, want_rsv_sz, new_sz, sfp->sgat_elem_sz);
+ if (blen == new_sz)
+ return 0;
+ n_srp = sg_mk_srp_sgat(sfp, true /* can take time */, new_sz);
+ if (IS_ERR(n_srp))
+ return PTR_ERR(n_srp);
+ sg_rq_state_force(n_srp, SG_RS_INACTIVE);
+ /* new sg_request object, sized correctly is now available */
+try_again:
+ o_srp = sfp->rsv_srp;
+ if (!o_srp) {
+ res = -EPROTO;
+ goto fini;
+ }
+ if (SG_RS_ACTIVE(o_srp) ||
+ test_bit(SG_FFD_MMAP_CALLED, sfp->ffd_bm)) {
+ res = -EBUSY;
+ goto fini;
+ }
+ use_new_srp = true;
+ xa_for_each(xafp, idx, t_srp) {
+ if (t_srp != o_srp && new_sz <= t_srp->sgat_h.buflen &&
+ !SG_RS_ACTIVE(t_srp)) {
+ /* good candidate on free list, use */
+ use_new_srp = false;
+ sfp->rsv_srp = t_srp;
+ break;
}
- sg_remove_sgat(sfp, &sfp->reserve);
- sg_build_reserve(sfp, want_rsv_sz);
}
- return 0;
+ if (use_new_srp) {
+ struct sg_request *cxc_srp;
+
+ xa_lock_irqsave(xafp, iflags);
+ n_srp->rq_idx = o_srp->rq_idx;
+ idx = o_srp->rq_idx;
+ cxc_srp = __xa_cmpxchg(xafp, idx, o_srp, n_srp, GFP_ATOMIC);
+ if (o_srp == cxc_srp) {
+ sfp->rsv_srp = n_srp;
+ sg_rq_state_force(n_srp, SG_RS_INACTIVE);
+ xa_unlock_irqrestore(xafp, iflags);
+ SG_LOG(6, sfp, "%s: new rsv srp=0x%pK ++\n", __func__,
+ n_srp);
+ sg_remove_sgat(o_srp);
+ kfree(o_srp);
+ } else {
+ xa_unlock_irqrestore(xafp, iflags);
+ SG_LOG(1, sfp, "%s: xa_cmpxchg() failed, again\n",
+ __func__);
+ goto try_again;
+ }
+ }
+fini:
+ if (!use_new_srp) {
+ sg_remove_sgat(n_srp);
+ kfree(n_srp); /* no-one else has seen n_srp, so safe */
+ }
+ return res;
}

#ifdef CONFIG_COMPAT
@@ -1363,26 +1514,43 @@ static int put_compat_request_table(struct compat_sg_req_info __user *o,
}
#endif

+/*
+ * For backward compatibility, output SG_MAX_QUEUE sg_req_info objects. First
+ * fetch from the active list then, if there is still room, from the free
+ * list. Some of the trailing elements may be empty which is indicated by all
+ * fields being zero. Any requests beyond SG_MAX_QUEUE are ignored.
+ */
static int
sg_ctl_req_tbl(struct sg_fd *sfp, void __user *p)
{
- int result, val;
+ int k, result, val;
unsigned long idx;
struct sg_request *srp;
- sg_req_info_t *rinfop;
+ struct sg_req_info *rinfop;

- rinfop = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
- GFP_KERNEL);
+ SG_LOG(3, sfp, "%s: SG_GET_REQUEST_TABLE\n", __func__);
+ k = SG_MAX_QUEUE;
+ rinfop = kcalloc(k, SZ_SG_REQ_INFO, GFP_KERNEL);
if (!rinfop)
return -ENOMEM;
val = 0;
xa_for_each(&sfp->srp_arr, idx, srp) {
if (!srp)
continue;
- if (xa_get_mark(&sfp->srp_arr, idx, SG_XA_RQ_AWAIT))
+ if (val >= SG_MAX_QUEUE)
+ break;
+ if (xa_get_mark(&sfp->srp_arr, idx, SG_XA_RQ_INACTIVE))
+ continue;
+ sg_fill_request_element(sfp, srp, rinfop + val);
+ val++;
+ }
+ xa_for_each(&sfp->srp_arr, idx, srp) {
+ if (!srp)
continue;
if (val >= SG_MAX_QUEUE)
break;
+ if (!xa_get_mark(&sfp->srp_arr, idx, SG_XA_RQ_INACTIVE))
+ continue;
sg_fill_request_element(sfp, srp, rinfop + val);
val++;
}
@@ -1449,18 +1617,15 @@ sg_ioctl_common(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
result = get_user(val, ip);
if (result)
return result;
- sfp->force_packid = val ? 1 : 0;
+ assign_bit(SG_FFD_FORCE_PACKID, sfp->ffd_bm, !!val);
return 0;
case SG_GET_PACK_ID: /* or tag of oldest "read"-able, -1 if none */
val = -1;
- srp = NULL;
xa_for_each_marked(&sfp->srp_arr, idx, srp, SG_XA_RQ_AWAIT) {
if (!srp)
continue;
- if ((1 == srp->done) && (!srp->sg_io_owned)) {
- val = srp->header.pack_id;
- break;
- }
+ val = srp->pack_id;
+ break;
}
SG_LOG(3, sfp, "%s: SG_GET_PACK_ID=%d\n", __func__, val);
return put_user(val, ip);
@@ -1471,44 +1636,48 @@ sg_ioctl_common(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
sdp->max_sgat_sz);
return put_user(sdp->max_sgat_sz, ip);
case SG_SET_RESERVED_SIZE:
- mutex_lock(&sfp->f_mutex);
result = get_user(val, ip);
if (!result) {
if (val >= 0 && val <= (1024 * 1024 * 1024)) {
+ mutex_lock(&sfp->f_mutex);
result = sg_set_reserved_sz(sfp, val);
+ mutex_unlock(&sfp->f_mutex);
} else {
SG_LOG(3, sfp, "%s: invalid size\n", __func__);
result = -EINVAL;
}
}
- mutex_unlock(&sfp->f_mutex);
return result;
case SG_GET_RESERVED_SIZE:
- val = min_t(int, sfp->reserve.buflen,
- max_sectors_bytes(sdev->request_queue));
+ mutex_lock(&sfp->f_mutex);
+ val = min_t(int, sfp->rsv_srp->sgat_h.buflen,
+ sdp->max_sgat_sz);
+ mutex_unlock(&sfp->f_mutex);
SG_LOG(3, sfp, "%s: SG_GET_RESERVED_SIZE=%d\n",
__func__, val);
- return put_user(val, ip);
+ result = put_user(val, ip);
+ return result;
case SG_SET_COMMAND_Q:
SG_LOG(3, sfp, "%s: SG_SET_COMMAND_Q\n", __func__);
result = get_user(val, ip);
if (result)
return result;
- sfp->cmd_q = val ? 1 : 0;
+ assign_bit(SG_FFD_CMD_Q, sfp->ffd_bm, !!val);
return 0;
case SG_GET_COMMAND_Q:
SG_LOG(3, sfp, "%s: SG_GET_COMMAND_Q\n", __func__);
- return put_user((int) sfp->cmd_q, ip);
+ return put_user(test_bit(SG_FFD_CMD_Q, sfp->ffd_bm), ip);
case SG_SET_KEEP_ORPHAN:
SG_LOG(3, sfp, "%s: SG_SET_KEEP_ORPHAN\n", __func__);
result = get_user(val, ip);
if (result)
return result;
- sfp->keep_orphan = val;
+ assign_bit(SG_FFD_KEEP_ORPHAN, sfp->ffd_bm, !!val);
return 0;
case SG_GET_KEEP_ORPHAN:
SG_LOG(3, sfp, "%s: SG_GET_KEEP_ORPHAN\n", __func__);
- return put_user((int) sfp->keep_orphan, ip);
+ return put_user(test_bit(SG_FFD_KEEP_ORPHAN, sfp->ffd_bm),
+ ip);
case SG_GET_VERSION_NUM:
SG_LOG(3, sfp, "%s: SG_GET_VERSION_NUM\n", __func__);
return put_user(sg_version_num, ip);
@@ -1563,6 +1732,8 @@ sg_ioctl_common(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
return put_user(val, ip);
case SG_EMULATED_HOST:
SG_LOG(3, sfp, "%s: SG_EMULATED_HOST\n", __func__);
+ if (unlikely(SG_IS_DETACHING(sdp)))
+ return -ENODEV;
return put_user(sdev->host->hostt->emulated, ip);
case SCSI_IOCTL_SEND_COMMAND:
SG_LOG(3, sfp, "%s: SCSI_IOCTL_SEND_COMMAND\n", __func__);
@@ -1573,7 +1744,7 @@ sg_ioctl_common(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
result = get_user(val, ip);
if (result)
return result;
- assign_bit(SG_FDEV_LOG_SENSE, sdp->fdev_bm, val);
+ assign_bit(SG_FDEV_LOG_SENSE, sdp->fdev_bm, !!val);
if (val == 0) /* user can force recalculation */
sg_calc_sgat_param(sdp);
return 0;
@@ -1618,7 +1789,7 @@ sg_ioctl_common(struct file *filp, struct sg_device *sdp, struct sg_fd *sfp,
break;
}
result = sg_allow_if_err_recovery(sdp, filp->f_flags & O_NDELAY);
- if (result)
+ if (unlikely(result))
return result;
return -ENOIOCTLCMD;
}
@@ -1681,7 +1852,7 @@ sg_poll(struct file *filp, poll_table * wait)

if (unlikely(SG_IS_DETACHING(sfp->parentdp)))
p_res |= EPOLLHUP;
- else if (likely(sfp->cmd_q))
+ else if (likely(test_bit(SG_FFD_CMD_Q, sfp->ffd_bm)))
p_res |= EPOLLOUT | EPOLLWRNORM;
else if (atomic_read(&sfp->submitted) == 0)
p_res |= EPOLLOUT | EPOLLWRNORM;
@@ -1703,9 +1874,10 @@ static vm_fault_t
sg_vma_fault(struct vm_fault *vmf)
{
int k, length;
- unsigned long offset, len, sa;
+ unsigned long offset, len, sa, iflags;
struct vm_area_struct *vma = vmf->vma;
struct sg_scatter_hold *rsv_schp;
+ struct sg_request *srp;
struct sg_device *sdp;
struct sg_fd *sfp;
const char *nbp = "==NULL, bad";
@@ -1724,12 +1896,18 @@ sg_vma_fault(struct vm_fault *vmf)
SG_LOG(1, sfp, "%s: device detaching\n", __func__);
goto out_err;
}
- rsv_schp = &sfp->reserve;
+ srp = sfp->rsv_srp;
+ if (!srp) {
+ SG_LOG(1, sfp, "%s: srp%s\n", __func__, nbp);
+ goto out_err;
+ }
+ xa_lock_irqsave(&sfp->srp_arr, iflags);
+ rsv_schp = &srp->sgat_h;
offset = vmf->pgoff << PAGE_SHIFT;
if (offset >= (unsigned int)rsv_schp->buflen) {
SG_LOG(1, sfp, "%s: offset[%lu] >= rsv.buflen\n", __func__,
offset);
- goto out_err;
+ goto out_err_unlock;
}
sa = vma->vm_start;
SG_LOG(3, sfp, "%s: vm_start=0x%lx, off=%lu\n", __func__, sa, offset);
@@ -1742,6 +1920,7 @@ sg_vma_fault(struct vm_fault *vmf)
struct page *pp;

pp = rsv_schp->pages[k];
+ xa_unlock_irqrestore(&sfp->srp_arr, iflags);
page = nth_page(pp, offset >> PAGE_SHIFT);
get_page(page); /* increment page count */
vmf->page = page;
@@ -1750,6 +1929,8 @@ sg_vma_fault(struct vm_fault *vmf)
sa += len;
offset -= len;
}
+out_err_unlock:
+ xa_unlock_irqrestore(&sfp->srp_arr, iflags);
out_err:
return VM_FAULT_SIGBUS;
}
@@ -1764,9 +1945,10 @@ sg_mmap(struct file *filp, struct vm_area_struct *vma)
{
int k, length;
int ret = 0;
- unsigned long req_sz, len, sa;
+ unsigned long req_sz, len, sa, iflags;
struct sg_scatter_hold *rsv_schp;
struct sg_fd *sfp;
+ struct sg_request *srp;

if (!filp || !vma)
return -ENXIO;
@@ -1782,11 +1964,13 @@ sg_mmap(struct file *filp, struct vm_area_struct *vma)
return -EINVAL; /* only an offset of 0 accepted */
/* Check reserve request is inactive and has large enough buffer */
mutex_lock(&sfp->f_mutex);
- if (sfp->res_in_use) {
+ srp = sfp->rsv_srp;
+ xa_lock_irqsave(&sfp->srp_arr, iflags);
+ if (SG_RS_ACTIVE(srp)) {
ret = -EBUSY;
goto out;
}
- rsv_schp = &sfp->reserve;
+ rsv_schp = &srp->sgat_h;
if (req_sz > (unsigned long)rsv_schp->buflen) {
ret = -ENOMEM;
goto out;
@@ -1799,11 +1983,12 @@ sg_mmap(struct file *filp, struct vm_area_struct *vma)
sa += len;
}

- sfp->mmap_called = 1;
+ set_bit(SG_FFD_MMAP_CALLED, sfp->ffd_bm);
vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_private_data = sfp;
vma->vm_ops = &sg_mmap_vm_ops;
out:
+ xa_unlock_irqrestore(&sfp->srp_arr, iflags);
mutex_unlock(&sfp->f_mutex);
return ret;
}
@@ -1825,8 +2010,10 @@ sg_rq_end_io_usercontext(struct work_struct *work)
return;
}
SG_LOG(3, sfp, "%s: srp=0x%pK\n", __func__, srp);
- sg_finish_scsi_blk_rq(srp);
- sg_deact_request(sfp, srp);
+ if (test_bit(SG_FRQ_DEACT_ORPHAN, srp->frq_bm)) {
+ sg_finish_scsi_blk_rq(srp); /* clean up orphan case */
+ sg_deact_request(sfp, srp);
+ }
kref_put(&sfp->f_ref, sg_remove_sfp);
}

@@ -1864,85 +2051,100 @@ sg_check_sense(struct sg_device *sdp, struct sg_request *srp, int sense_len)
}

/*
- * This function is a "bottom half" handler that is called by the mid
- * level when a command is completed (or has failed).
+ * This "bottom half" (soft interrupt) handler is called by the mid-level
+ * when a request has completed or failed. This callback is registered in a
+ * blk_execute_rq_nowait() call in the sg_common_write(). For ioctl(SG_IO)
+ * (sync) usage, sg_ctl_sg_io() waits to be woken up by this callback.
*/
static void
sg_rq_end_io(struct request *rq, blk_status_t status)
{
+ enum sg_rq_state rqq_state = SG_RS_AWAIT_RCV;
+ int a_resid, slen;
struct sg_request *srp = rq->end_io_data;
struct scsi_request *scsi_rp = scsi_req(rq);
struct sg_device *sdp;
struct sg_fd *sfp;
- unsigned int ms;
- int resid, slen;
- int done = 1;
- unsigned long iflags;

- if (WARN_ON(srp->done != 0))
+ if (!scsi_rp) {
+ WARN_ONCE("%s: scsi_req(rq) unexpectedly NULL\n", __func__);
return;
-
- sfp = srp->parentfp;
- if (WARN_ON(sfp == NULL))
+ }
+ if (!srp) {
+ WARN_ONCE("%s: srp unexpectedly NULL\n", __func__);
return;
-
+ }
+ /* Expect 0 --> 1 transition, otherwise processed elsewhere */
+ if (unlikely(test_and_set_bit(SG_FRQ_BLK_PUT_REQ, srp->frq_bm))) {
+ pr_info("%s: srp=%pK already completed\n", __func__, srp);
+ return;
+ }
+ if (WARN_ON(atomic_read(&srp->rq_st) != SG_RS_INFLIGHT)) {
+ pr_warn("%s: bad rq_st=%d\n", __func__,
+ atomic_read(&srp->rq_st));
+ goto early_err;
+ }
+ sfp = srp->parentfp;
+ if (unlikely(!sfp)) {
+ WARN_ONCE(1, "%s: sfp unexpectedly NULL", __func__);
+ goto early_err;
+ }
sdp = sfp->parentdp;
if (unlikely(SG_IS_DETACHING(sdp)))
pr_info("%s: device detaching\n", __func__);

srp->rq_result = scsi_rp->result;
- resid = scsi_rp->resid_len;
-
- srp->header.resid = resid;
-
slen = min_t(int, scsi_rp->sense_len, SCSI_SENSE_BUFFERSIZE);
+ a_resid = scsi_rp->resid_len;
+
+ if (a_resid)
+ srp->in_resid = a_resid;

- SG_LOG(6, sfp, "%s: pack_id=%d, res=0x%x\n", __func__,
- srp->header.pack_id, srp->rq_result);
- ms = jiffies_to_msecs(jiffies);
- srp->header.duration = (ms > srp->header.duration) ?
- (ms - srp->header.duration) : 0;
- if (srp->rq_result != 0 && slen > 0)
+ SG_LOG(6, sfp, "%s: pack_id=%d, res=0x%x\n", __func__, srp->pack_id,
+ srp->rq_result);
+ srp->duration = sg_calc_rq_dur(srp);
+ if (unlikely((srp->rq_result & SG_ML_RESULT_MSK) && slen > 0))
sg_check_sense(sdp, srp, slen);
if (slen > 0)
memcpy(srp->sense_b, scsi_rp->sense, slen);
-
- /* Rely on write phase to clean out srp status values, so no "else" */
-
- if (!srp->sg_io_owned)
+ srp->sense_len = slen;
+ if (unlikely(test_bit(SG_FRQ_IS_ORPHAN, srp->frq_bm))) {
+ if (test_bit(SG_FFD_KEEP_ORPHAN, sfp->ffd_bm)) {
+ clear_bit(SG_FRQ_SYNC_INVOC, srp->frq_bm);
+ } else {
+ rqq_state = SG_RS_BUSY;
+ set_bit(SG_FRQ_DEACT_ORPHAN, srp->frq_bm);
+ }
+ }
+ if (!test_bit(SG_FRQ_SYNC_INVOC, srp->frq_bm))
atomic_inc(&sfp->waiting);
+ if (unlikely(sg_rq_state_chg(srp, SG_RS_INFLIGHT, rqq_state,
+ false, __func__)))
+ pr_warn("%s: can't set rq_st\n", __func__);
/*
- * Free the request as soon as it is complete so that its resources
- * can be reused without waiting for userspace to read() the
- * result. But keep the associated bio (if any) around until
- * blk_rq_unmap_user() can be called from user context.
+ * Free the mid-level resources apart from the bio (if any). The bio's
+ * blk_rq_unmap_user() can be called later from user context.
*/
srp->rq = NULL;
- scsi_req_free_cmd(scsi_req(rq));
+ scsi_req_free_cmd(scsi_rp);
blk_put_request(rq);

- if (unlikely(srp->orphan)) {
- if (sfp->keep_orphan)
- srp->sg_io_owned = 0;
- else
- done = 0;
- }
- srp->done = done;
-
- if (likely(done)) {
- /* Now wake up any sg_read() that is waiting for this
- * packet.
- */
- xa_lock_irqsave(&sfp->srp_arr, iflags);
- __xa_set_mark(&sfp->srp_arr, srp->rq_idx, SG_XA_RQ_AWAIT);
- xa_unlock_irqrestore(&sfp->srp_arr, iflags);
+ if (likely(rqq_state == SG_RS_AWAIT_RCV)) {
+ /* Wake any sg_read()/ioctl(SG_IORECEIVE) awaiting this req */
wake_up_interruptible(&sfp->read_wait);
kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
kref_put(&sfp->f_ref, sg_remove_sfp);
- } else {
+ } else { /* clean up orphaned request that aren't being kept */
INIT_WORK(&srp->ew_orph.work, sg_rq_end_io_usercontext);
schedule_work(&srp->ew_orph.work);
}
+ return;
+
+early_err:
+ srp->rq = NULL;
+ if (scsi_rp)
+ scsi_req_free_cmd(scsi_rp);
+ blk_put_request(rq);
}

static const struct file_operations sg_fops = {
@@ -1970,9 +2172,9 @@ static struct sg_device *
sg_add_device_helper(struct gendisk *disk, struct scsi_device *scsidp)
{
struct sg_device *sdp;
- unsigned long iflags;
int error;
u32 k;
+ unsigned long iflags;

sdp = kzalloc(sizeof(*sdp), GFP_KERNEL);
if (!sdp)
@@ -1990,7 +2192,7 @@ sg_add_device_helper(struct gendisk *disk, struct scsi_device *scsidp)
error = -ENODEV;
} else {
sdev_printk(KERN_WARNING, scsidp,
- "%s: idr alloc sg_device failure: %d\n",
+ "%s: idr allocation sg_device failure: %d\n",
__func__, error);
}
goto out_unlock;
@@ -2192,6 +2394,7 @@ init_sg(void)
SG_MAX_DEVS, "sg");
if (rc)
return rc;
+
pr_info("Registered %s[char major=0x%x], version: %s, date: %s\n",
"sg device ", SCSI_GENERIC_MAJOR, SG_VERSION_STR,
sg_version_date);
@@ -2207,6 +2410,7 @@ init_sg(void)
return 0;
}
class_destroy(sg_sysfs_class);
+
err_out_unreg:
unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
return rc;
@@ -2233,6 +2437,19 @@ exit_sg(void)
idr_destroy(&sg_index_idr);
}

+static inline bool
+sg_chk_dio_allowed(struct sg_device *sdp, struct sg_request *srp,
+ int iov_count, int dir)
+{
+ if (sg_allow_dio && (srp->rq_flags & SG_FLAG_DIRECT_IO)) {
+ if (dir != SG_DXFER_UNKNOWN && !iov_count) {
+ if (!sdp->device->host->unchecked_isa_dma)
+ return true;
+ }
+ }
+ return false;
+}
+
static void
sg_set_map_data(const struct sg_scatter_hold *schp, bool up_valid,
struct rq_map_data *mdp)
@@ -2246,31 +2463,40 @@ sg_set_map_data(const struct sg_scatter_hold *schp, bool up_valid,
}

static int
-sg_start_req(struct sg_request *srp, u8 *cmd)
+sg_start_req(struct sg_request *srp, u8 *cmd, int cmd_len, int dxfer_dir)
{
- int res;
+ bool reserved, us_xfer;
+ int res = 0;
+ int dxfer_len = 0;
+ int r0w = READ;
+ unsigned int iov_count = 0;
+ void __user *up;
struct request *rq;
- struct scsi_request *req;
+ struct scsi_request *scsi_rp;
struct sg_fd *sfp = srp->parentfp;
- struct sg_io_hdr *hp = &srp->header;
- int dxfer_len = (int) hp->dxfer_len;
- int dxfer_dir = hp->dxfer_direction;
- unsigned int iov_count = hp->iovec_count;
- struct sg_scatter_hold *req_schp = &srp->data;
- struct sg_scatter_hold *rsv_schp = &sfp->reserve;
- struct request_queue *q = sfp->parentdp->device->request_queue;
- struct rq_map_data *md, map_data;
- int r0w = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
+ struct sg_device *sdp;
+ struct sg_scatter_hold *req_schp;
+ struct request_queue *q;
+ struct rq_map_data *md = (void *)srp; /* want any non-NULL value */
u8 *long_cmdp = NULL;
+ __maybe_unused const char *cp = "";
+ struct sg_slice_hdr3 *sh3p = &srp->s_hdr3;
+ struct rq_map_data map_data;

- if (hp->cmd_len > BLK_MAX_CDB) {
- long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
+ sdp = sfp->parentdp;
+ if (cmd_len > BLK_MAX_CDB) { /* for longer SCSI cdb_s */
+ long_cmdp = kzalloc(cmd_len, GFP_KERNEL);
if (!long_cmdp)
return -ENOMEM;
SG_LOG(5, sfp, "%s: long_cmdp=0x%pK ++\n", __func__, long_cmdp);
}
+ up = sh3p->dxferp;
+ dxfer_len = (int)sh3p->dxfer_len;
+ iov_count = sh3p->iovec_count;
+ r0w = dxfer_dir == SG_DXFER_TO_DEV ? WRITE : READ;
SG_LOG(4, sfp, "%s: dxfer_len=%d, data-%s\n", __func__, dxfer_len,
(r0w ? "OUT" : "IN"));
+ q = sdp->device->request_queue;

/*
* NOTE
@@ -2283,125 +2509,148 @@ sg_start_req(struct sg_request *srp, u8 *cmd)
* do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
* not expect an EWOULDBLOCK from this condition.
*/
- rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
- REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
+ rq = blk_get_request(q, (r0w ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN), 0);
if (IS_ERR(rq)) {
kfree(long_cmdp);
return PTR_ERR(rq);
}
- req = scsi_req(rq);
-
- if (hp->cmd_len > BLK_MAX_CDB)
- req->cmd = long_cmdp;
- memcpy(req->cmd, cmd, hp->cmd_len);
- req->cmd_len = hp->cmd_len;
-
+ /* current sg_request protected by SG_RS_BUSY state */
+ scsi_rp = scsi_req(rq);
srp->rq = rq;
- rq->end_io_data = srp;
- req->retries = SG_DEFAULT_RETRIES;
-
- if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
- return 0;

- if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
- dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
- !sfp->parentdp->device->host->unchecked_isa_dma &&
- blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
+ if (cmd_len > BLK_MAX_CDB)
+ scsi_rp->cmd = long_cmdp;
+ memcpy(scsi_rp->cmd, cmd, cmd_len);
+ scsi_rp->cmd_len = cmd_len;
+ us_xfer = !(srp->rq_flags & SG_FLAG_NO_DXFER);
+ assign_bit(SG_FRQ_NO_US_XFER, srp->frq_bm, !us_xfer);
+ reserved = (sfp->rsv_srp == srp);
+ rq->end_io_data = srp;
+ scsi_rp->retries = SG_DEFAULT_RETRIES;
+ req_schp = &srp->sgat_h;
+
+ if (dxfer_len <= 0 || dxfer_dir == SG_DXFER_NONE) {
+ SG_LOG(4, sfp, "%s: no data xfer [0x%pK]\n", __func__, srp);
+ set_bit(SG_FRQ_NO_US_XFER, srp->frq_bm);
+ goto fini; /* path of reqs with no din nor dout */
+ } else if (sg_chk_dio_allowed(sdp, srp, iov_count, dxfer_dir) &&
+ blk_rq_aligned(q, (unsigned long)up, dxfer_len)) {
+ srp->rq_info |= SG_INFO_DIRECT_IO;
md = NULL;
- else
+ if (IS_ENABLED(CONFIG_SCSI_PROC_FS))
+ cp = "direct_io, ";
+ } else { /* normal IO and failed conditions for dio path */
md = &map_data;
+ }

- if (md) {
- mutex_lock(&sfp->f_mutex);
- if (dxfer_len <= rsv_schp->buflen &&
- !sfp->res_in_use) {
- sfp->res_in_use = 1;
- sg_link_reserve(sfp, srp, dxfer_len);
- } else if (hp->flags & SG_FLAG_MMAP_IO) {
- res = -EBUSY; /* sfp->res_in_use == 1 */
- if (dxfer_len > rsv_schp->buflen)
- res = -ENOMEM;
- mutex_unlock(&sfp->f_mutex);
- return res;
- } else {
- res = sg_mk_sgat(req_schp, sfp, dxfer_len);
- if (res) {
- mutex_unlock(&sfp->f_mutex);
- return res;
- }
+ if (likely(md)) { /* normal, "indirect" IO */
+ if (unlikely((srp->rq_flags & SG_FLAG_MMAP_IO))) {
+ /* mmap IO must use and fit in reserve request */
+ if (!reserved || dxfer_len > req_schp->buflen)
+ res = reserved ? -ENOMEM : -EBUSY;
+ } else if (req_schp->buflen == 0) {
+ int up_sz = max_t(int, dxfer_len, sfp->sgat_elem_sz);
+
+ res = sg_mk_sgat(srp, sfp, up_sz);
}
- mutex_unlock(&sfp->f_mutex);
+ if (res)
+ goto fini;

- sg_set_map_data(req_schp, !!hp->dxferp, md);
+ sg_set_map_data(req_schp, !!up, md);
md->from_user = (dxfer_dir == SG_DXFER_TO_FROM_DEV);
}

- if (iov_count) {
+ if (unlikely(iov_count)) {
struct iovec *iov = NULL;
struct iov_iter i;

- res = import_iovec(r0w, hp->dxferp, iov_count, 0, &iov, &i);
+ res = import_iovec(r0w, up, iov_count, 0, &iov, &i);
if (res < 0)
- return res;
+ goto fini;

- iov_iter_truncate(&i, hp->dxfer_len);
+ iov_iter_truncate(&i, dxfer_len);
if (!iov_iter_count(&i)) {
kfree(iov);
- return -EINVAL;
+ res = -EINVAL;
+ goto fini;
}

- res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
+ if (us_xfer)
+ res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
kfree(iov);
- } else
- res = blk_rq_map_user(q, rq, md, hp->dxferp,
- hp->dxfer_len, GFP_ATOMIC);
-
- if (!res) {
- srp->bio = rq->bio;
-
- if (!md) {
- req_schp->dio_in_use = 1;
- hp->info |= SG_INFO_DIRECT_IO;
+ if (IS_ENABLED(CONFIG_SCSI_PROC_FS))
+ cp = "iov_count > 0";
+ } else if (us_xfer) { /* setup for transfer data to/from user space */
+ res = blk_rq_map_user(q, rq, md, up, dxfer_len, GFP_ATOMIC);
+ if (IS_ENABLED(CONFIG_SCSI_PROC_FS) && res)
+ SG_LOG(1, sfp, "%s: blk_rq_map_user() res=%d\n",
+ __func__, res);
+ }
+fini:
+ if (unlikely(res)) { /* failure, free up resources */
+ scsi_req_free_cmd(scsi_rp);
+ if (likely(!test_and_set_bit(SG_FRQ_BLK_PUT_REQ,
+ srp->frq_bm))) {
+ srp->rq = NULL;
+ blk_put_request(rq);
}
+ } else {
+ srp->bio = rq->bio;
}
+ SG_LOG((res ? 1 : 4), sfp, "%s: %s res=%d [0x%pK]\n", __func__, cp,
+ res, srp);
return res;
}

+/*
+ * Clean up mid-level and block layer resources of finished request. Sometimes
+ * blk_rq_unmap_user() returns -4 (-EINTR) and this is why: "If we're in a
+ * workqueue, the request is orphaned, so don't copy into a random user
+ * address space, just free and return -EINTR so user space doesn't expect
+ * any data." [block/bio.c]
+ */
static void
sg_finish_scsi_blk_rq(struct sg_request *srp)
{
int ret;
-
struct sg_fd *sfp = srp->parentfp;
- struct sg_scatter_hold *req_schp = &srp->data;

SG_LOG(4, sfp, "%s: srp=0x%pK%s\n", __func__, srp,
- (srp->res_used) ? " rsv" : "");
- if (!srp->sg_io_owned) {
+ (srp->parentfp->rsv_srp == srp) ? " rsv" : "");
+ if (!test_bit(SG_FRQ_SYNC_INVOC, srp->frq_bm)) {
atomic_dec(&sfp->submitted);
atomic_dec(&sfp->waiting);
}
if (srp->bio) {
- ret = blk_rq_unmap_user(srp->bio);
- if (ret) /* -EINTR (-4) can be ignored */
- SG_LOG(6, sfp, "%s: blk_rq_unmap_user() --> %d\n",
- __func__, ret);
+ bool us_xfer = !test_bit(SG_FRQ_NO_US_XFER, srp->frq_bm);
+
+ if (us_xfer) {
+ ret = blk_rq_unmap_user(srp->bio);
+ if (ret) { /* -EINTR (-4) can be ignored */
+ SG_LOG(6, sfp,
+ "%s: blk_rq_unmap_user() --> %d\n",
+ __func__, ret);
+ }
+ }
srp->bio = NULL;
}
+ /* In worst case READ data returned to user space by this point */

- if (srp->rq) {
- scsi_req_free_cmd(scsi_req(srp->rq));
- blk_put_request(srp->rq);
- }
+ /* Expect blk_put_request(rq) already called in sg_rq_end_io() */
+ if (unlikely(!test_and_set_bit(SG_FRQ_BLK_PUT_REQ, srp->frq_bm))) {
+ struct request *rq = srp->rq;

- if (srp->res_used)
- sg_unlink_reserve(sfp, srp);
- else
- sg_remove_sgat(sfp, req_schp);
+ if (rq) { /* blk_get_request() may have failed */
+ if (scsi_req(rq))
+ scsi_req_free_cmd(scsi_req(rq));
+ srp->rq = NULL;
+ blk_put_request(rq);
+ }
+ }
}

static int
-sg_mk_sgat(struct sg_scatter_hold *schp, struct sg_fd *sfp, int minlen)
+sg_mk_sgat(struct sg_request *srp, struct sg_fd *sfp, int minlen)
{
int j, k, rem_sz, align_sz, order, o_order;
int mx_sgat_elems = sfp->parentdp->max_sgat_elems;
@@ -2410,6 +2659,7 @@ sg_mk_sgat(struct sg_scatter_hold *schp, struct sg_fd *sfp, int minlen)
gfp_t mask_ap = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
gfp_t mask_kz = GFP_ATOMIC | __GFP_NOWARN;
struct sg_device *sdp = sfp->parentdp;
+ struct sg_scatter_hold *schp = &srp->sgat_h;

if (unlikely(minlen <= 0)) {
if (minlen < 0)
@@ -2420,9 +2670,8 @@ sg_mk_sgat(struct sg_scatter_hold *schp, struct sg_fd *sfp, int minlen)
align_sz = ALIGN(minlen, SG_DEF_SECTOR_SZ);

schp->pages = kcalloc(mx_sgat_elems, ptr_sz, mask_kz);
- SG_LOG(4, sfp, "%s: minlen=%d, align_sz=%d [sz=%zu, 0x%pK ++]\n",
- __func__, minlen, align_sz, mx_sgat_elems * ptr_sz,
- schp->pages);
+ SG_LOG(4, sfp, "%s: minlen=%d [sz=%zu, 0x%pK ++]\n", __func__, minlen,
+ mx_sgat_elems * ptr_sz, schp->pages);
if (unlikely(!schp->pages))
return -ENOMEM;

@@ -2486,13 +2735,15 @@ sg_remove_sgat_helper(struct sg_fd *sfp, struct sg_scatter_hold *schp)

/* Remove the data (possibly a sgat list) held by srp, not srp itself */
static void
-sg_remove_sgat(struct sg_fd *sfp, struct sg_scatter_hold *schp)
+sg_remove_sgat(struct sg_request *srp)
{
+ struct sg_scatter_hold *schp = &srp->sgat_h; /* care: remove own data */
+ struct sg_fd *sfp = srp->parentfp;
+
SG_LOG(4, sfp, "%s: num_sgat=%d%s\n", __func__, schp->num_sgat,
- ((sfp ? (&sfp->reserve == schp) : false) ?
+ ((srp->parentfp ? (sfp->rsv_srp == srp) : false) ?
" [rsv]" : ""));
- if (!schp->dio_in_use)
- sg_remove_sgat_helper(sfp, schp);
+ sg_remove_sgat_helper(sfp, schp);

memset(schp, 0, sizeof(*schp)); /* zeros buflen and dlen */
}
@@ -2507,7 +2758,7 @@ sg_read_append(struct sg_request *srp, void __user *outp, int num_xfer)
{
int k, num, res;
struct page *pgp;
- struct sg_scatter_hold *schp = &srp->data;
+ struct sg_scatter_hold *schp = &srp->sgat_h;

SG_LOG(4, srp->parentfp, "%s: num_xfer=%d\n", __func__, num_xfer);
if (unlikely(!outp || num_xfer <= 0))
@@ -2521,11 +2772,11 @@ sg_read_append(struct sg_request *srp, void __user *outp, int num_xfer)
break;
}
if (num > num_xfer) {
- if (__copy_to_user(outp, page_address(pgp), num_xfer))
+ if (copy_to_user(outp, page_address(pgp), num_xfer))
res = -EFAULT;
break;
} else {
- if (__copy_to_user(outp, page_address(pgp), num)) {
+ if (copy_to_user(outp, page_address(pgp), num)) {
res = -EFAULT;
break;
}
@@ -2548,135 +2799,273 @@ sg_read_append(struct sg_request *srp, void __user *outp, int num_xfer)
static struct sg_request *
sg_find_srp_by_id(struct sg_fd *sfp, int pack_id)
{
+ __maybe_unused bool is_bad_st = false;
+ __maybe_unused enum sg_rq_state bad_sr_st = SG_RS_INACTIVE;
+ bool search_for_1 = (pack_id != SG_PACK_ID_WILDCARD);
+ int res;
+ int num_waiting = atomic_read(&sfp->waiting);
unsigned long idx;
- struct sg_request *resp;
+ struct sg_request *srp = NULL;
+ struct xarray *xafp = &sfp->srp_arr;

- xa_for_each_marked(&sfp->srp_arr, idx, resp, SG_XA_RQ_AWAIT) {
- if (!resp)
- continue;
- /* look for requests that are ready + not SG_IO owned */
- if (resp->done == 1 && !resp->sg_io_owned &&
- (-1 == pack_id || resp->header.pack_id == pack_id)) {
- resp->done = 2; /* guard against other readers */
- return resp;
+ if (num_waiting < 1)
+ return NULL;
+ if (unlikely(search_for_1)) {
+ xa_for_each_marked(xafp, idx, srp, SG_XA_RQ_AWAIT) {
+ if (!srp)
+ continue;
+ if (srp->pack_id != pack_id)
+ continue;
+ res = sg_rq_state_chg(srp, SG_RS_AWAIT_RCV, SG_RS_BUSY,
+ false, __func__);
+ if (likely(res == 0))
+ goto good;
+ /* else another caller got it, move on */
+ if (IS_ENABLED(CONFIG_SCSI_PROC_FS)) {
+ is_bad_st = true;
+ bad_sr_st = atomic_read(&srp->rq_st);
+ }
+ break;
+ }
+ } else { /* search for any request is more likely */
+ xa_for_each_marked(xafp, idx, srp, SG_XA_RQ_AWAIT) {
+ if (!srp)
+ continue;
+ res = sg_rq_state_chg(srp, SG_RS_AWAIT_RCV, SG_RS_BUSY,
+ false, __func__);
+ if (likely(res == 0))
+ goto good;
+ }
+ }
+ /* here if one of above loops does _not_ find a match */
+ if (IS_ENABLED(CONFIG_SCSI_PROC_FS)) {
+ if (search_for_1) {
+ const char *cptp = "pack_id=";
+
+ if (is_bad_st)
+ SG_LOG(1, sfp, "%s: %s%d wrong state: %s\n",
+ __func__, cptp, pack_id,
+ sg_rq_st_str(bad_sr_st, true));
+ else
+ SG_LOG(6, sfp, "%s: %s%d not awaiting read\n",
+ __func__, cptp, pack_id);
}
}
return NULL;
+good:
+ SG_LOG(6, sfp, "%s: %s%d found [srp=0x%pK]\n", __func__, "pack_id=",
+ pack_id, srp);
+ return srp;
}

-static void
-sg_link_reserve(struct sg_fd *sfp, struct sg_request *srp, int size)
+/*
+ * Makes a new sg_request object. If 'first' is set then use GFP_KERNEL which
+ * may take time but has improved chance of success, otherwise use GFP_ATOMIC.
+ * Note that basic initialization is done but srp is not added to either sfp
+ * list. On error returns twisted negated errno value (not NULL).
+ */
+static struct sg_request *
+sg_mk_srp(struct sg_fd *sfp, bool first)
{
- struct sg_scatter_hold *req_schp = &srp->data;
- struct sg_scatter_hold *rsv_schp = &sfp->reserve;
- int k, num, rem;
-
- srp->res_used = 1;
- SG_LOG(4, sfp, "%s: size=%d\n", __func__, size);
- rem = size;
-
- num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
- for (k = 0; k < rsv_schp->num_sgat; k++) {
- if (rem <= num) {
- req_schp->num_sgat = k + 1;
- req_schp->sglist_len = rsv_schp->sglist_len;
- req_schp->pages = rsv_schp->pages;
+ struct sg_request *srp;
+ gfp_t gfp = __GFP_NOWARN;

- req_schp->buflen = size;
- req_schp->page_order = rsv_schp->page_order;
- break;
- } else
- rem -= num;
+ if (first) /* prepared to wait if none already outstanding */
+ srp = kzalloc(sizeof(*srp), gfp | GFP_KERNEL);
+ else
+ srp = kzalloc(sizeof(*srp), gfp | GFP_ATOMIC);
+ if (srp) {
+ atomic_set(&srp->rq_st, SG_RS_BUSY);
+ srp->parentfp = sfp;
+ return srp;
+ } else {
+ return ERR_PTR(-ENOMEM);
}
-
- if (k >= rsv_schp->num_sgat)
- SG_LOG(1, sfp, "%s: BAD size\n", __func__);
}

-static void
-sg_unlink_reserve(struct sg_fd *sfp, struct sg_request *srp)
+static struct sg_request *
+sg_mk_srp_sgat(struct sg_fd *sfp, bool first, int db_len)
{
- struct sg_scatter_hold *req_schp = &srp->data;
+ int res;
+ struct sg_request *n_srp = sg_mk_srp(sfp, first);

- SG_LOG(4, srp->parentfp, "%s: req->num_sgat=%d\n", __func__,
- (int)req_schp->num_sgat);
- req_schp->num_sgat = 0;
- req_schp->buflen = 0;
- req_schp->pages = NULL;
- req_schp->page_order = 0;
- req_schp->sglist_len = 0;
- srp->res_used = 0;
- /* Called without mutex lock to avoid deadlock */
- sfp->res_in_use = 0;
+ if (IS_ERR(n_srp))
+ return n_srp;
+ if (db_len > 0) {
+ res = sg_mk_sgat(n_srp, sfp, db_len);
+ if (res) {
+ kfree(n_srp);
+ return ERR_PTR(res);
+ }
+ }
+ return n_srp;
}

-static void
-sg_build_reserve(struct sg_fd *sfp, int req_size)
+/*
+ * Irrespective of the given reserve request size, the minimum size requested
+ * will be PAGE_SIZE (often 4096 bytes). Returns a pointer to reserve object or
+ * a negated errno value twisted by ERR_PTR() macro. The actual number of bytes
+ * allocated (maybe less than buflen) is in srp->sgat_h.buflen . Note that this
+ * function is only called in contexts where locking is not required.
+ */
+static struct sg_request *
+sg_build_reserve(struct sg_fd *sfp, int buflen)
{
- struct sg_scatter_hold *schp = &sfp->reserve;
+ bool go_out = false;
+ int res;
+ struct sg_request *srp;

- SG_LOG(3, sfp, "%s: buflen=%d\n", __func__, req_size);
+ SG_LOG(3, sfp, "%s: buflen=%d\n", __func__, buflen);
+ srp = sg_mk_srp(sfp, xa_empty(&sfp->srp_arr));
+ if (IS_ERR(srp))
+ return srp;
+ sfp->rsv_srp = srp;
do {
- if (req_size < PAGE_SIZE)
- req_size = PAGE_SIZE;
- if (sg_mk_sgat(schp, sfp, req_size) == 0)
- return;
- sg_remove_sgat(sfp, schp);
- req_size >>= 1; /* divide by 2 */
- } while (req_size > (PAGE_SIZE / 2));
+ if (buflen < (int)PAGE_SIZE) {
+ buflen = PAGE_SIZE;
+ go_out = true;
+ }
+ res = sg_mk_sgat(srp, sfp, buflen);
+ if (res == 0) {
+ SG_LOG(4, sfp, "%s: final buflen=%d, srp=0x%pK ++\n",
+ __func__, buflen, srp);
+ return srp;
+ }
+ if (go_out)
+ return ERR_PTR(res);
+ /* failed so remove, halve buflen, try again */
+ sg_remove_sgat(srp);
+ buflen >>= 1; /* divide by 2 */
+ } while (true);
}

-/* always adds to end of list */
+/*
+ * Setup an active request (soon to carry a SCSI command) to the current file
+ * descriptor by creating a new one or re-using a request from the free
+ * list (fl). If successful returns a valid pointer in SG_RS_BUSY state. On
+ * failure returns a negated errno value twisted by ERR_PTR() macro.
+ */
static struct sg_request *
-sg_setup_req(struct sg_fd *sfp)
+sg_setup_req(struct sg_fd *sfp, int dxfr_len, struct sg_comm_wr_t *cwrp)
{
+ bool act_empty = false;
bool found = false;
+ bool mk_new_srp = false;
+ bool try_harder = false;
int res;
- unsigned long idx, iflags;
- struct sg_request *rp;
+ int num_inactive = 0;
+ unsigned long idx, last_idx, iflags;
+ struct sg_request *r_srp = NULL; /* request to return */
struct xarray *xafp = &sfp->srp_arr;
-
- if (!xa_empty(xafp)) {
- xa_for_each_marked(xafp, idx, rp, SG_XA_RQ_INACTIVE) {
- if (!rp)
+ __maybe_unused const char *cp;
+
+start_again:
+ cp = "";
+ if (xa_empty(xafp)) {
+ act_empty = true;
+ mk_new_srp = true;
+ } else if (!try_harder && dxfr_len < SG_DEF_SECTOR_SZ) {
+ last_idx = ~0UL;
+ xa_for_each_marked(xafp, idx, r_srp, SG_XA_RQ_INACTIVE) {
+ if (!r_srp)
continue;
- if (sg_rstate_chg(rp, SG_RS_INACTIVE, SG_RS_BUSY))
+ ++num_inactive;
+ if (dxfr_len < SG_DEF_SECTOR_SZ) {
+ last_idx = idx;
continue;
- memset(rp, 0, sizeof(*rp));
- rp->rq_idx = idx;
- xa_lock_irqsave(xafp, iflags);
- __xa_clear_mark(xafp, idx, SG_XA_RQ_INACTIVE);
- xa_unlock_irqrestore(xafp, iflags);
+ }
+ }
+ /* If dxfr_len is small, use last inactive request */
+ if (last_idx != ~0UL) {
+ idx = last_idx;
+ r_srp = xa_load(xafp, idx);
+ if (!r_srp)
+ goto start_again;
+ if (sg_rq_state_chg(r_srp, SG_RS_INACTIVE, SG_RS_BUSY,
+ false, __func__))
+ goto start_again; /* gone to another thread */
+ cp = "toward back of srp_arr";
found = true;
- break;
+ }
+ } else {
+ xa_for_each_marked(xafp, idx, r_srp, SG_XA_RQ_INACTIVE) {
+ if (!r_srp)
+ continue;
+ if (r_srp->sgat_h.buflen >= dxfr_len) {
+ if (sg_rq_state_chg
+ (r_srp, SG_RS_INACTIVE, SG_RS_BUSY,
+ false, __func__))
+ continue;
+ cp = "from front of srp_arr";
+ found = true;
+ break;
+ }
}
}
- if (!found) {
- rp = kzalloc(sizeof(*rp), GFP_KERNEL);
- if (!rp)
- return NULL;
+ if (found) {
+ r_srp->in_resid = 0;
+ r_srp->rq_info = 0;
+ r_srp->sense_len = 0;
+ mk_new_srp = false;
+ } else {
+ mk_new_srp = true;
}
- rp->parentfp = sfp;
- rp->header.duration = jiffies_to_msecs(jiffies);
- if (!found) {
+ if (mk_new_srp) {
+ bool allow_cmd_q = test_bit(SG_FFD_CMD_Q, sfp->ffd_bm);
u32 n_idx;
struct xa_limit xal = { .max = 0, .min = 0 };

- atomic_set(&rp->rq_st, SG_RS_BUSY);
+ cp = "new";
+ if (!allow_cmd_q && atomic_read(&sfp->submitted) > 0) {
+ r_srp = ERR_PTR(-EDOM);
+ SG_LOG(6, sfp, "%s: trying 2nd req but cmd_q=false\n",
+ __func__);
+ goto fini;
+ }
+ r_srp = sg_mk_srp_sgat(sfp, act_empty, dxfr_len);
+ if (IS_ERR(r_srp)) {
+ if (!try_harder && dxfr_len < SG_DEF_SECTOR_SZ &&
+ num_inactive > 0) {
+ try_harder = true;
+ goto start_again;
+ }
+ goto fini;
+ }
+ atomic_set(&r_srp->rq_st, SG_RS_BUSY);
xa_lock_irqsave(xafp, iflags);
xal.max = atomic_inc_return(&sfp->req_cnt);
- res = __xa_alloc(xafp, &n_idx, rp, xal, GFP_KERNEL);
+ res = __xa_alloc(xafp, &n_idx, r_srp, xal, GFP_KERNEL);
xa_unlock_irqrestore(xafp, iflags);
if (res < 0) {
- pr_warn("%s: don't expect xa_alloc() to fail, errno=%d\n",
- __func__, -res);
- return NULL;
+ SG_LOG(1, sfp, "%s: xa_alloc() failed, errno=%d\n",
+ __func__, -res);
+ sg_remove_sgat(r_srp);
+ kfree(r_srp);
+ r_srp = ERR_PTR(-EPROTOTYPE);
+ goto fini;
}
- rp->rq_idx = n_idx;
- }
- return rp;
+ idx = n_idx;
+ r_srp->rq_idx = idx;
+ r_srp->parentfp = sfp;
+ SG_LOG(4, sfp, "%s: mk_new_srp=0x%pK ++\n", __func__, r_srp);
+ }
+ r_srp->frq_bm[0] = cwrp->frq_bm[0]; /* assumes <= 32 req flags */
+ r_srp->sgat_h.dlen = dxfr_len;/* must be <= r_srp->sgat_h.buflen */
+ r_srp->cmd_opcode = 0xff; /* set invalid opcode (VS), 0x0 is TUR */
+fini:
+ if (IS_ERR(r_srp))
+ SG_LOG(1, sfp, "%s: err=%ld\n", __func__, PTR_ERR(r_srp));
+ if (!IS_ERR(r_srp))
+ SG_LOG(4, sfp, "%s: %s r_srp=0x%pK\n", __func__, cp, r_srp);
+ return r_srp;
}

+/*
+ * Moves a completed sg_request object to the free list and sets it to
+ * SG_RS_INACTIVE which makes it available for re-use. Requests with no data
+ * associated are appended to the tail of the free list while other requests
+ * are prepended to the head of the free list.
+ */
static void
sg_deact_request(struct sg_fd *sfp, struct sg_request *srp)
{
@@ -2684,34 +3073,43 @@ sg_deact_request(struct sg_fd *sfp, struct sg_request *srp)

if (WARN_ON(!sfp || !srp))
return;
+ atomic_set(&srp->rq_st, SG_RS_INACTIVE);
xa_lock_irqsave(&sfp->srp_arr, iflags);
__xa_set_mark(&sfp->srp_arr, srp->rq_idx, SG_XA_RQ_INACTIVE);
+ __xa_clear_mark(&sfp->srp_arr, srp->rq_idx, SG_XA_RQ_AWAIT);
xa_unlock_irqrestore(&sfp->srp_arr, iflags);
- atomic_set(&srp->rq_st, SG_RS_INACTIVE);
}

+/* Returns pointer to sg_fd object or negated errno twisted by ERR_PTR */
static struct sg_fd *
sg_add_sfp(struct sg_device *sdp)
{
+ bool reduced = false;
int rbuf_len, res;
u32 idx;
+ long err;
unsigned long iflags;
struct sg_fd *sfp;
+ struct sg_request *srp = NULL;
+ struct xarray *xadp = &sdp->sfp_arr;
+ struct xarray *xafp;
struct xa_limit xal;

sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
if (!sfp)
return ERR_PTR(-ENOMEM);
-
init_waitqueue_head(&sfp->read_wait);
xa_init_flags(&sfp->srp_arr, XA_FLAGS_ALLOC | XA_FLAGS_LOCK_IRQ);
+ xafp = &sfp->srp_arr;
kref_init(&sfp->f_ref);
mutex_init(&sfp->f_mutex);
sfp->timeout = SG_DEFAULT_TIMEOUT;
sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
- sfp->force_packid = SG_DEF_FORCE_PACK_ID;
- sfp->cmd_q = SG_DEF_COMMAND_Q;
- sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
+ /* other bits in sfp->ffd_bm[1] cleared by kzalloc() above */
+ __assign_bit(SG_FFD_FORCE_PACKID, sfp->ffd_bm, SG_DEF_FORCE_PACK_ID);
+ __assign_bit(SG_FFD_CMD_Q, sfp->ffd_bm, SG_DEF_COMMAND_Q);
+ __assign_bit(SG_FFD_KEEP_ORPHAN, sfp->ffd_bm, SG_DEF_KEEP_ORPHAN);
+ __assign_bit(SG_FFD_Q_AT_TAIL, sfp->ffd_bm, SG_DEFAULT_Q_AT);
/*
* SG_SCATTER_SZ initializes scatter_elem_sz but different value may
* be given as driver/module parameter (e.g. 'scatter_elem_sz=8192').
@@ -2725,28 +3123,64 @@ sg_add_sfp(struct sg_device *sdp)
atomic_set(&sfp->waiting, 0);
atomic_set(&sfp->req_cnt, 0);

- if (SG_IS_DETACHING(sdp)) {
+ if (unlikely(SG_IS_DETACHING(sdp))) {
+ SG_LOG(1, sfp, "%s: detaching\n", __func__);
kfree(sfp);
return ERR_PTR(-ENODEV);
}
- SG_LOG(3, sfp, "%s: sfp=0x%pK\n", __func__, sfp);
if (unlikely(sg_big_buff != def_reserved_size))
sg_big_buff = def_reserved_size;

rbuf_len = min_t(int, sg_big_buff, sdp->max_sgat_sz);
- if (rbuf_len > 0)
- sg_build_reserve(sfp, rbuf_len);
-
- xa_lock_irqsave(&sdp->sfp_arr, iflags);
+ if (rbuf_len > 0) {
+ struct xa_limit xalrq = { .max = 0, .min = 0 };
+
+ srp = sg_build_reserve(sfp, rbuf_len);
+ if (IS_ERR(srp)) {
+ kfree(sfp);
+ err = PTR_ERR(srp);
+ SG_LOG(1, sfp, "%s: build reserve err=%ld\n", __func__,
+ -err);
+ return ERR_PTR(err);
+ }
+ if (srp->sgat_h.buflen < rbuf_len) {
+ reduced = true;
+ SG_LOG(2, sfp,
+ "%s: reserve reduced from %d to buflen=%d\n",
+ __func__, rbuf_len, srp->sgat_h.buflen);
+ }
+ xa_lock_irqsave(xafp, iflags);
+ xalrq.max = atomic_inc_return(&sfp->req_cnt);
+ res = __xa_alloc(xafp, &idx, srp, xalrq, GFP_ATOMIC);
+ xa_unlock_irqrestore(xafp, iflags);
+ if (res < 0) {
+ SG_LOG(1, sfp, "%s: xa_alloc(srp) bad, errno=%d\n",
+ __func__, -res);
+ sg_remove_sgat(srp);
+ kfree(srp);
+ kfree(sfp);
+ return ERR_PTR(-EPROTOTYPE);
+ }
+ srp->rq_idx = idx;
+ srp->parentfp = sfp;
+ sg_rq_state_chg(srp, 0, SG_RS_INACTIVE, true, __func__);
+ }
+ if (!reduced) {
+ SG_LOG(4, sfp, "%s: built reserve buflen=%d\n", __func__,
+ rbuf_len);
+ }
+ xa_lock_irqsave(xadp, iflags);
xal.min = 0;
xal.max = atomic_read(&sdp->open_cnt);
- res = __xa_alloc(&sdp->sfp_arr, &idx, sfp, xal, GFP_KERNEL);
- xa_unlock_irqrestore(&sdp->sfp_arr, iflags);
+ res = __xa_alloc(xadp, &idx, sfp, xal, GFP_KERNEL);
+ xa_unlock_irqrestore(xadp, iflags);
if (res < 0) {
pr_warn("%s: xa_alloc(sdp) bad, o_count=%d, errno=%d\n",
__func__, xal.max, -res);
- if (rbuf_len > 0)
- sg_remove_sgat(sfp, &sfp->reserve);
+ if (srp) {
+ sg_remove_sgat(srp);
+ kfree(srp);
+ }
kfree(sfp);
return ERR_PTR(res);
}
@@ -2777,12 +3211,14 @@ sg_remove_sfp_usercontext(struct work_struct *work)
struct sg_request *srp;
struct sg_request *e_srp;
struct xarray *xafp = &sfp->srp_arr;
+ struct xarray *xadp;

if (!sfp) {
pr_warn("sg: %s: sfp is NULL\n", __func__);
return;
}
sdp = sfp->parentdp;
+ xadp = &sdp->sfp_arr;

/* Cleanup any responses which were never read(). */
xa_for_each(xafp, idx, srp) {
@@ -2790,24 +3226,20 @@ sg_remove_sfp_usercontext(struct work_struct *work)
continue;
if (!xa_get_mark(xafp, srp->rq_idx, SG_XA_RQ_INACTIVE))
sg_finish_scsi_blk_rq(srp);
+ sg_remove_sgat(srp);
xa_lock_irqsave(xafp, iflags);
e_srp = __xa_erase(xafp, srp->rq_idx);
xa_unlock_irqrestore(xafp, iflags);
if (srp != e_srp)
SG_LOG(1, sfp, "%s: xa_erase() return unexpected\n",
__func__);
+ SG_LOG(6, sfp, "%s: kfree: srp=%pK --\n", __func__, srp);
kfree(srp);
}
xa_destroy(xafp);
- if (sfp->reserve.buflen > 0) {
- SG_LOG(6, sfp, "%s: buflen=%d, num_sgat=%d\n", __func__,
- (int)sfp->reserve.buflen, (int)sfp->reserve.num_sgat);
- sg_remove_sgat(sfp, &sfp->reserve);
- }
-
- xa_lock_irqsave(&sdp->sfp_arr, iflags);
- e_sfp = __xa_erase(&sdp->sfp_arr, sfp->idx);
- xa_unlock_irqrestore(&sdp->sfp_arr, iflags);
+ xa_lock_irqsave(xadp, iflags);
+ e_sfp = __xa_erase(xadp, sfp->idx);
+ xa_unlock_irqrestore(xadp, iflags);
if (unlikely(sfp != e_sfp))
SG_LOG(1, sfp, "%s: xa_erase() return unexpected\n",
__func__);
@@ -3059,6 +3491,7 @@ sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
struct sg_proc_deviter {
loff_t index;
size_t max;
+ int fd_index;
};

static void *
@@ -3142,11 +3575,10 @@ sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
static void
sg_proc_debug_helper(struct seq_file *s, struct sg_device *sdp)
{
- int k, new_interface, blen, usg;
+ int k;
unsigned long idx, idx2;
struct sg_request *srp;
struct sg_fd *fp;
- const struct sg_io_hdr *hp;
const char * cp;
unsigned int ms;

@@ -3157,51 +3589,53 @@ sg_proc_debug_helper(struct seq_file *s, struct sg_device *sdp)
k++;
seq_printf(s, " FD(%d): timeout=%dms buflen=%d (res)sgat=%d low_dma=%d idx=%lu\n",
k, jiffies_to_msecs(fp->timeout),
- fp->reserve.buflen, (int)fp->reserve.num_sgat,
+ fp->rsv_srp->sgat_h.buflen,
+ (int)fp->rsv_srp->sgat_h.num_sgat,
(int)sdp->device->host->unchecked_isa_dma, idx);
seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
- (int) fp->cmd_q, (int) fp->force_packid,
- (int) fp->keep_orphan);
+ (int)test_bit(SG_FFD_CMD_Q, fp->ffd_bm),
+ (int)test_bit(SG_FFD_FORCE_PACKID, fp->ffd_bm),
+ (int)test_bit(SG_FFD_KEEP_ORPHAN, fp->ffd_bm));
seq_printf(s, " submitted=%d waiting=%d\n",
atomic_read(&fp->submitted),
atomic_read(&fp->waiting));
xa_for_each(&fp->srp_arr, idx2, srp) {
+ const struct sg_slice_hdr3 *sh3p = &srp->s_hdr3;
+ bool is_v3 = (sh3p->interface_id != '\0');
+ enum sg_rq_state rq_st = atomic_read(&srp->rq_st);
+
if (!srp)
continue;
- hp = &srp->header;
- new_interface = (hp->interface_id == '\0') ? 0 : 1;
- if (srp->res_used) {
- if (new_interface &&
- (SG_FLAG_MMAP_IO & hp->flags))
+ if (srp->parentfp->rsv_srp == srp) {
+ if (is_v3 && (SG_FLAG_MMAP_IO & sh3p->flags))
cp = " mmap>> ";
else
cp = " rb>> ";
} else {
- if (SG_INFO_DIRECT_IO_MASK & hp->info)
+ if (SG_INFO_DIRECT_IO_MASK & srp->rq_info)
cp = " dio>> ";
else
cp = " ";
}
seq_puts(s, cp);
- blen = srp->data.buflen;
- usg = srp->data.num_sgat;
- seq_puts(s, srp->done ?
- ((1 == srp->done) ? "rcv:" : "fin:")
- : "act:");
- seq_printf(s, " id=%d blen=%d",
- srp->header.pack_id, blen);
- if (srp->done)
- seq_printf(s, " dur=%d", hp->duration);
- else {
- ms = jiffies_to_msecs(jiffies);
- seq_printf(s, " t_o/elap=%d/%d",
- (new_interface ? hp->timeout :
- jiffies_to_msecs(fp->timeout)),
- (ms > hp->duration ? ms - hp->duration : 0));
+ seq_puts(s, sg_rq_st_str(rq_st, false));
+ seq_printf(s, ": id=%d len/blen=%d/%d",
+ srp->pack_id, srp->sgat_h.dlen,
+ srp->sgat_h.buflen);
+ if (rq_st == SG_RS_AWAIT_RCV ||
+ rq_st == SG_RS_RCV_DONE) {
+ seq_printf(s, " dur=%d", srp->duration);
+ goto fin_line;
}
- seq_printf(s, "ms sgat=%d op=0x%02x dummy: %s\n", usg,
- (int)srp->data.cmd_opcode,
- sg_rq_st_str(SG_RS_INACTIVE, false));
+ ms = jiffies_to_msecs(jiffies);
+ seq_printf(s, " t_o/elap=%d/%d",
+ (is_v3 ? sh3p->timeout :
+ jiffies_to_msecs(fp->timeout)),
+ (ms > srp->duration ? ms - srp->duration :
+ 0));
+fin_line:
+ seq_printf(s, "ms sgat=%d op=0x%02x\n",
+ srp->sgat_h.num_sgat, (int)srp->cmd_opcode);
}
if (xa_empty(&fp->srp_arr))
seq_puts(s, " No requests active\n");
--
2.25.1