Commit b8d8bdfe authored by Jens Axboe's avatar Jens Axboe

Merge branch 'stable/for-jens-3.2' of git://oss.oracle.com/git/kwilk/xen into for-3.2/drivers

parents 4c823cc3 6927d920
...@@ -39,6 +39,9 @@ ...@@ -39,6 +39,9 @@
#include <linux/list.h> #include <linux/list.h>
#include <linux/delay.h> #include <linux/delay.h>
#include <linux/freezer.h> #include <linux/freezer.h>
#include <linux/loop.h>
#include <linux/falloc.h>
#include <linux/fs.h>
#include <xen/events.h> #include <xen/events.h>
#include <xen/page.h> #include <xen/page.h>
...@@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id) ...@@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
static void print_stats(struct xen_blkif *blkif) static void print_stats(struct xen_blkif *blkif)
{ {
pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d\n", pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d"
" | ds %4d\n",
current->comm, blkif->st_oo_req, current->comm, blkif->st_oo_req,
blkif->st_rd_req, blkif->st_wr_req, blkif->st_f_req); blkif->st_rd_req, blkif->st_wr_req,
blkif->st_f_req, blkif->st_ds_req);
blkif->st_print = jiffies + msecs_to_jiffies(10 * 1000); blkif->st_print = jiffies + msecs_to_jiffies(10 * 1000);
blkif->st_rd_req = 0; blkif->st_rd_req = 0;
blkif->st_wr_req = 0; blkif->st_wr_req = 0;
blkif->st_oo_req = 0; blkif->st_oo_req = 0;
blkif->st_ds_req = 0;
} }
int xen_blkif_schedule(void *arg) int xen_blkif_schedule(void *arg)
...@@ -410,6 +416,59 @@ static int xen_blkbk_map(struct blkif_request *req, ...@@ -410,6 +416,59 @@ static int xen_blkbk_map(struct blkif_request *req,
return ret; return ret;
} }
static void xen_blk_discard(struct xen_blkif *blkif, struct blkif_request *req)
{
int err = 0;
int status = BLKIF_RSP_OKAY;
struct block_device *bdev = blkif->vbd.bdev;
if (blkif->blk_backend_type == BLKIF_BACKEND_PHY)
/* just forward the discard request */
err = blkdev_issue_discard(bdev,
req->u.discard.sector_number,
req->u.discard.nr_sectors,
GFP_KERNEL, 0);
else if (blkif->blk_backend_type == BLKIF_BACKEND_FILE) {
/* punch a hole in the backing file */
struct loop_device *lo = bdev->bd_disk->private_data;
struct file *file = lo->lo_backing_file;
if (file->f_op->fallocate)
err = file->f_op->fallocate(file,
FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
req->u.discard.sector_number << 9,
req->u.discard.nr_sectors << 9);
else
err = -EOPNOTSUPP;
} else
err = -EOPNOTSUPP;
if (err == -EOPNOTSUPP) {
pr_debug(DRV_PFX "discard op failed, not supported\n");
status = BLKIF_RSP_EOPNOTSUPP;
} else if (err)
status = BLKIF_RSP_ERROR;
make_response(blkif, req->id, req->operation, status);
}
static void xen_blk_drain_io(struct xen_blkif *blkif)
{
atomic_set(&blkif->drain, 1);
do {
/* The initial value is one, and one refcnt taken at the
* start of the xen_blkif_schedule thread. */
if (atomic_read(&blkif->refcnt) <= 2)
break;
wait_for_completion_interruptible_timeout(
&blkif->drain_complete, HZ);
if (!atomic_read(&blkif->drain))
break;
} while (!kthread_should_stop());
atomic_set(&blkif->drain, 0);
}
/* /*
* Completion callback on the bio's. Called as bh->b_end_io() * Completion callback on the bio's. Called as bh->b_end_io()
*/ */
...@@ -422,6 +481,11 @@ static void __end_block_io_op(struct pending_req *pending_req, int error) ...@@ -422,6 +481,11 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
pr_debug(DRV_PFX "flush diskcache op failed, not supported\n"); pr_debug(DRV_PFX "flush diskcache op failed, not supported\n");
xen_blkbk_flush_diskcache(XBT_NIL, pending_req->blkif->be, 0); xen_blkbk_flush_diskcache(XBT_NIL, pending_req->blkif->be, 0);
pending_req->status = BLKIF_RSP_EOPNOTSUPP; pending_req->status = BLKIF_RSP_EOPNOTSUPP;
} else if ((pending_req->operation == BLKIF_OP_WRITE_BARRIER) &&
(error == -EOPNOTSUPP)) {
pr_debug(DRV_PFX "write barrier op failed, not supported\n");
xen_blkbk_barrier(XBT_NIL, pending_req->blkif->be, 0);
pending_req->status = BLKIF_RSP_EOPNOTSUPP;
} else if (error) { } else if (error) {
pr_debug(DRV_PFX "Buffer not up-to-date at end of operation," pr_debug(DRV_PFX "Buffer not up-to-date at end of operation,"
" error=%d\n", error); " error=%d\n", error);
...@@ -438,6 +502,10 @@ static void __end_block_io_op(struct pending_req *pending_req, int error) ...@@ -438,6 +502,10 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
make_response(pending_req->blkif, pending_req->id, make_response(pending_req->blkif, pending_req->id,
pending_req->operation, pending_req->status); pending_req->operation, pending_req->status);
xen_blkif_put(pending_req->blkif); xen_blkif_put(pending_req->blkif);
if (atomic_read(&pending_req->blkif->refcnt) <= 2) {
if (atomic_read(&pending_req->blkif->drain))
complete(&pending_req->blkif->drain_complete);
}
free_req(pending_req); free_req(pending_req);
} }
} }
...@@ -532,7 +600,6 @@ do_block_io_op(struct xen_blkif *blkif) ...@@ -532,7 +600,6 @@ do_block_io_op(struct xen_blkif *blkif)
return more_to_do; return more_to_do;
} }
/* /*
* Transmutation of the 'struct blkif_request' to a proper 'struct bio' * Transmutation of the 'struct blkif_request' to a proper 'struct bio'
* and call the 'submit_bio' to pass it to the underlying storage. * and call the 'submit_bio' to pass it to the underlying storage.
...@@ -549,6 +616,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -549,6 +616,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
int i, nbio = 0; int i, nbio = 0;
int operation; int operation;
struct blk_plug plug; struct blk_plug plug;
bool drain = false;
switch (req->operation) { switch (req->operation) {
case BLKIF_OP_READ: case BLKIF_OP_READ:
...@@ -559,11 +627,16 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -559,11 +627,16 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
blkif->st_wr_req++; blkif->st_wr_req++;
operation = WRITE_ODIRECT; operation = WRITE_ODIRECT;
break; break;
case BLKIF_OP_WRITE_BARRIER:
drain = true;
case BLKIF_OP_FLUSH_DISKCACHE: case BLKIF_OP_FLUSH_DISKCACHE:
blkif->st_f_req++; blkif->st_f_req++;
operation = WRITE_FLUSH; operation = WRITE_FLUSH;
break; break;
case BLKIF_OP_WRITE_BARRIER: case BLKIF_OP_DISCARD:
blkif->st_ds_req++;
operation = REQ_DISCARD;
break;
default: default:
operation = 0; /* make gcc happy */ operation = 0; /* make gcc happy */
goto fail_response; goto fail_response;
...@@ -572,7 +645,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -572,7 +645,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
/* Check that the number of segments is sane. */ /* Check that the number of segments is sane. */
nseg = req->nr_segments; nseg = req->nr_segments;
if (unlikely(nseg == 0 && operation != WRITE_FLUSH) || if (unlikely(nseg == 0 && operation != WRITE_FLUSH &&
operation != REQ_DISCARD) ||
unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) { unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) {
pr_debug(DRV_PFX "Bad number of segments in request (%d)\n", pr_debug(DRV_PFX "Bad number of segments in request (%d)\n",
nseg); nseg);
...@@ -621,16 +695,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -621,16 +695,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
} }
} }
/* Wait on all outstanding I/O's and once that has been completed
* issue the WRITE_FLUSH.
*/
if (drain)
xen_blk_drain_io(pending_req->blkif);
/* /*
* If we have failed at this point, we need to undo the M2P override, * If we have failed at this point, we need to undo the M2P override,
* set gnttab_set_unmap_op on all of the grant references and perform * set gnttab_set_unmap_op on all of the grant references and perform
* the hypercall to unmap the grants - that is all done in * the hypercall to unmap the grants - that is all done in
* xen_blkbk_unmap. * xen_blkbk_unmap.
*/ */
if (xen_blkbk_map(req, pending_req, seg)) if (operation != REQ_DISCARD && xen_blkbk_map(req, pending_req, seg))
goto fail_flush; goto fail_flush;
/* This corresponding xen_blkif_put is done in __end_block_io_op */ /*
* This corresponding xen_blkif_put is done in __end_block_io_op, or
* below (in "!bio") if we are handling a BLKIF_OP_DISCARD.
*/
xen_blkif_get(blkif); xen_blkif_get(blkif);
for (i = 0; i < nseg; i++) { for (i = 0; i < nseg; i++) {
...@@ -654,10 +737,11 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -654,10 +737,11 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
preq.sector_number += seg[i].nsec; preq.sector_number += seg[i].nsec;
} }
/* This will be hit if the operation was a flush. */ /* This will be hit if the operation was a flush or discard. */
if (!bio) { if (!bio) {
BUG_ON(operation != WRITE_FLUSH); BUG_ON(operation != WRITE_FLUSH && operation != REQ_DISCARD);
if (operation == WRITE_FLUSH) {
bio = bio_alloc(GFP_KERNEL, 0); bio = bio_alloc(GFP_KERNEL, 0);
if (unlikely(bio == NULL)) if (unlikely(bio == NULL))
goto fail_put_bio; goto fail_put_bio;
...@@ -666,6 +750,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -666,6 +750,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
bio->bi_bdev = preq.bdev; bio->bi_bdev = preq.bdev;
bio->bi_private = pending_req; bio->bi_private = pending_req;
bio->bi_end_io = end_block_io_op; bio->bi_end_io = end_block_io_op;
} else if (operation == REQ_DISCARD) {
xen_blk_discard(blkif, req);
xen_blkif_put(blkif);
free_req(pending_req);
return 0;
}
} }
/* /*
...@@ -685,7 +775,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, ...@@ -685,7 +775,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
if (operation == READ) if (operation == READ)
blkif->st_rd_sect += preq.nr_sects; blkif->st_rd_sect += preq.nr_sects;
else if (operation == WRITE || operation == WRITE_FLUSH) else if (operation & WRITE)
blkif->st_wr_sect += preq.nr_sects; blkif->st_wr_sect += preq.nr_sects;
return 0; return 0;
...@@ -765,9 +855,9 @@ static int __init xen_blkif_init(void) ...@@ -765,9 +855,9 @@ static int __init xen_blkif_init(void)
mmap_pages = xen_blkif_reqs * BLKIF_MAX_SEGMENTS_PER_REQUEST; mmap_pages = xen_blkif_reqs * BLKIF_MAX_SEGMENTS_PER_REQUEST;
blkbk->pending_reqs = kmalloc(sizeof(blkbk->pending_reqs[0]) * blkbk->pending_reqs = kzalloc(sizeof(blkbk->pending_reqs[0]) *
xen_blkif_reqs, GFP_KERNEL); xen_blkif_reqs, GFP_KERNEL);
blkbk->pending_grant_handles = kzalloc(sizeof(blkbk->pending_grant_handles[0]) * blkbk->pending_grant_handles = kmalloc(sizeof(blkbk->pending_grant_handles[0]) *
mmap_pages, GFP_KERNEL); mmap_pages, GFP_KERNEL);
blkbk->pending_pages = kzalloc(sizeof(blkbk->pending_pages[0]) * blkbk->pending_pages = kzalloc(sizeof(blkbk->pending_pages[0]) *
mmap_pages, GFP_KERNEL); mmap_pages, GFP_KERNEL);
...@@ -790,8 +880,6 @@ static int __init xen_blkif_init(void) ...@@ -790,8 +880,6 @@ static int __init xen_blkif_init(void)
if (rc) if (rc)
goto failed_init; goto failed_init;
memset(blkbk->pending_reqs, 0, sizeof(blkbk->pending_reqs));
INIT_LIST_HEAD(&blkbk->pending_free); INIT_LIST_HEAD(&blkbk->pending_free);
spin_lock_init(&blkbk->pending_free_lock); spin_lock_init(&blkbk->pending_free_lock);
init_waitqueue_head(&blkbk->pending_free_wq); init_waitqueue_head(&blkbk->pending_free_wq);
......
...@@ -63,13 +63,26 @@ struct blkif_common_response { ...@@ -63,13 +63,26 @@ struct blkif_common_response {
/* i386 protocol version */ /* i386 protocol version */
#pragma pack(push, 4) #pragma pack(push, 4)
struct blkif_x86_32_request_rw {
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
struct blkif_x86_32_request_discard {
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
uint64_t nr_sectors;
};
struct blkif_x86_32_request { struct blkif_x86_32_request {
uint8_t operation; /* BLKIF_OP_??? */ uint8_t operation; /* BLKIF_OP_??? */
uint8_t nr_segments; /* number of segments */ uint8_t nr_segments; /* number of segments */
blkif_vdev_t handle; /* only for read/write requests */ blkif_vdev_t handle; /* only for read/write requests */
uint64_t id; /* private guest value, echoed in resp */ uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ union {
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct blkif_x86_32_request_rw rw;
struct blkif_x86_32_request_discard discard;
} u;
}; };
struct blkif_x86_32_response { struct blkif_x86_32_response {
uint64_t id; /* copied from request */ uint64_t id; /* copied from request */
...@@ -79,13 +92,26 @@ struct blkif_x86_32_response { ...@@ -79,13 +92,26 @@ struct blkif_x86_32_response {
#pragma pack(pop) #pragma pack(pop)
/* x86_64 protocol version */ /* x86_64 protocol version */
struct blkif_x86_64_request_rw {
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
struct blkif_x86_64_request_discard {
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
uint64_t nr_sectors;
};
struct blkif_x86_64_request { struct blkif_x86_64_request {
uint8_t operation; /* BLKIF_OP_??? */ uint8_t operation; /* BLKIF_OP_??? */
uint8_t nr_segments; /* number of segments */ uint8_t nr_segments; /* number of segments */
blkif_vdev_t handle; /* only for read/write requests */ blkif_vdev_t handle; /* only for read/write requests */
uint64_t __attribute__((__aligned__(8))) id; uint64_t __attribute__((__aligned__(8))) id;
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ union {
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct blkif_x86_64_request_rw rw;
struct blkif_x86_64_request_discard discard;
} u;
}; };
struct blkif_x86_64_response { struct blkif_x86_64_response {
uint64_t __attribute__((__aligned__(8))) id; uint64_t __attribute__((__aligned__(8))) id;
...@@ -113,6 +139,11 @@ enum blkif_protocol { ...@@ -113,6 +139,11 @@ enum blkif_protocol {
BLKIF_PROTOCOL_X86_64 = 3, BLKIF_PROTOCOL_X86_64 = 3,
}; };
enum blkif_backend_type {
BLKIF_BACKEND_PHY = 1,
BLKIF_BACKEND_FILE = 2,
};
struct xen_vbd { struct xen_vbd {
/* What the domain refers to this vbd as. */ /* What the domain refers to this vbd as. */
blkif_vdev_t handle; blkif_vdev_t handle;
...@@ -138,6 +169,7 @@ struct xen_blkif { ...@@ -138,6 +169,7 @@ struct xen_blkif {
unsigned int irq; unsigned int irq;
/* Comms information. */ /* Comms information. */
enum blkif_protocol blk_protocol; enum blkif_protocol blk_protocol;
enum blkif_backend_type blk_backend_type;
union blkif_back_rings blk_rings; union blkif_back_rings blk_rings;
struct vm_struct *blk_ring_area; struct vm_struct *blk_ring_area;
/* The VBD attached to this interface. */ /* The VBD attached to this interface. */
...@@ -149,6 +181,9 @@ struct xen_blkif { ...@@ -149,6 +181,9 @@ struct xen_blkif {
atomic_t refcnt; atomic_t refcnt;
wait_queue_head_t wq; wait_queue_head_t wq;
/* for barrier (drain) requests */
struct completion drain_complete;
atomic_t drain;
/* One thread per one blkif. */ /* One thread per one blkif. */
struct task_struct *xenblkd; struct task_struct *xenblkd;
unsigned int waiting_reqs; unsigned int waiting_reqs;
...@@ -159,6 +194,7 @@ struct xen_blkif { ...@@ -159,6 +194,7 @@ struct xen_blkif {
int st_wr_req; int st_wr_req;
int st_oo_req; int st_oo_req;
int st_f_req; int st_f_req;
int st_ds_req;
int st_rd_sect; int st_rd_sect;
int st_wr_sect; int st_wr_sect;
...@@ -182,7 +218,7 @@ struct xen_blkif { ...@@ -182,7 +218,7 @@ struct xen_blkif {
struct phys_req { struct phys_req {
unsigned short dev; unsigned short dev;
unsigned short nr_sects; blkif_sector_t nr_sects;
struct block_device *bdev; struct block_device *bdev;
blkif_sector_t sector_number; blkif_sector_t sector_number;
}; };
...@@ -196,6 +232,8 @@ int xen_blkif_schedule(void *arg); ...@@ -196,6 +232,8 @@ int xen_blkif_schedule(void *arg);
int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt, int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
struct backend_info *be, int state); struct backend_info *be, int state);
int xen_blkbk_barrier(struct xenbus_transaction xbt,
struct backend_info *be, int state);
struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be); struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be);
static inline void blkif_get_x86_32_req(struct blkif_request *dst, static inline void blkif_get_x86_32_req(struct blkif_request *dst,
...@@ -206,12 +244,25 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst, ...@@ -206,12 +244,25 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst,
dst->nr_segments = src->nr_segments; dst->nr_segments = src->nr_segments;
dst->handle = src->handle; dst->handle = src->handle;
dst->id = src->id; dst->id = src->id;
dst->u.rw.sector_number = src->sector_number; switch (src->operation) {
case BLKIF_OP_READ:
case BLKIF_OP_WRITE:
case BLKIF_OP_WRITE_BARRIER:
case BLKIF_OP_FLUSH_DISKCACHE:
dst->u.rw.sector_number = src->u.rw.sector_number;
barrier(); barrier();
if (n > dst->nr_segments) if (n > dst->nr_segments)
n = dst->nr_segments; n = dst->nr_segments;
for (i = 0; i < n; i++) for (i = 0; i < n; i++)
dst->u.rw.seg[i] = src->seg[i]; dst->u.rw.seg[i] = src->u.rw.seg[i];
break;
case BLKIF_OP_DISCARD:
dst->u.discard.sector_number = src->u.discard.sector_number;
dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
break;
default:
break;
}
} }
static inline void blkif_get_x86_64_req(struct blkif_request *dst, static inline void blkif_get_x86_64_req(struct blkif_request *dst,
...@@ -222,12 +273,25 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst, ...@@ -222,12 +273,25 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst,
dst->nr_segments = src->nr_segments; dst->nr_segments = src->nr_segments;
dst->handle = src->handle; dst->handle = src->handle;
dst->id = src->id; dst->id = src->id;
dst->u.rw.sector_number = src->sector_number; switch (src->operation) {
case BLKIF_OP_READ:
case BLKIF_OP_WRITE:
case BLKIF_OP_WRITE_BARRIER:
case BLKIF_OP_FLUSH_DISKCACHE:
dst->u.rw.sector_number = src->u.rw.sector_number;
barrier(); barrier();
if (n > dst->nr_segments) if (n > dst->nr_segments)
n = dst->nr_segments; n = dst->nr_segments;
for (i = 0; i < n; i++) for (i = 0; i < n; i++)
dst->u.rw.seg[i] = src->seg[i]; dst->u.rw.seg[i] = src->u.rw.seg[i];
break;
case BLKIF_OP_DISCARD:
dst->u.discard.sector_number = src->u.discard.sector_number;
dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
break;
default:
break;
}
} }
#endif /* __XEN_BLKIF__BACKEND__COMMON_H__ */ #endif /* __XEN_BLKIF__BACKEND__COMMON_H__ */
...@@ -114,6 +114,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid) ...@@ -114,6 +114,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
spin_lock_init(&blkif->blk_ring_lock); spin_lock_init(&blkif->blk_ring_lock);
atomic_set(&blkif->refcnt, 1); atomic_set(&blkif->refcnt, 1);
init_waitqueue_head(&blkif->wq); init_waitqueue_head(&blkif->wq);
init_completion(&blkif->drain_complete);
atomic_set(&blkif->drain, 0);
blkif->st_print = jiffies; blkif->st_print = jiffies;
init_waitqueue_head(&blkif->waiting_to_free); init_waitqueue_head(&blkif->waiting_to_free);
...@@ -272,6 +274,7 @@ VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req); ...@@ -272,6 +274,7 @@ VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req);
VBD_SHOW(rd_req, "%d\n", be->blkif->st_rd_req); VBD_SHOW(rd_req, "%d\n", be->blkif->st_rd_req);
VBD_SHOW(wr_req, "%d\n", be->blkif->st_wr_req); VBD_SHOW(wr_req, "%d\n", be->blkif->st_wr_req);
VBD_SHOW(f_req, "%d\n", be->blkif->st_f_req); VBD_SHOW(f_req, "%d\n", be->blkif->st_f_req);
VBD_SHOW(ds_req, "%d\n", be->blkif->st_ds_req);
VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect); VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect);
VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect); VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect);
...@@ -280,6 +283,7 @@ static struct attribute *xen_vbdstat_attrs[] = { ...@@ -280,6 +283,7 @@ static struct attribute *xen_vbdstat_attrs[] = {
&dev_attr_rd_req.attr, &dev_attr_rd_req.attr,
&dev_attr_wr_req.attr, &dev_attr_wr_req.attr,
&dev_attr_f_req.attr, &dev_attr_f_req.attr,
&dev_attr_ds_req.attr,
&dev_attr_rd_sect.attr, &dev_attr_rd_sect.attr,
&dev_attr_wr_sect.attr, &dev_attr_wr_sect.attr,
NULL NULL
...@@ -419,6 +423,73 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt, ...@@ -419,6 +423,73 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
return err; return err;
} }
int xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info *be)
{
struct xenbus_device *dev = be->dev;
struct xen_blkif *blkif = be->blkif;
char *type;
int err;
int state = 0;
type = xenbus_read(XBT_NIL, dev->nodename, "type", NULL);
if (!IS_ERR(type)) {
if (strncmp(type, "file", 4) == 0) {
state = 1;
blkif->blk_backend_type = BLKIF_BACKEND_FILE;
}
if (strncmp(type, "phy", 3) == 0) {
struct block_device *bdev = be->blkif->vbd.bdev;
struct request_queue *q = bdev_get_queue(bdev);
if (blk_queue_discard(q)) {
err = xenbus_printf(xbt, dev->nodename,
"discard-granularity", "%u",
q->limits.discard_granularity);
if (err) {
xenbus_dev_fatal(dev, err,
"writing discard-granularity");
goto kfree;
}
err = xenbus_printf(xbt, dev->nodename,
"discard-alignment", "%u",
q->limits.discard_alignment);
if (err) {
xenbus_dev_fatal(dev, err,
"writing discard-alignment");
goto kfree;
}
state = 1;
blkif->blk_backend_type = BLKIF_BACKEND_PHY;
}
}
} else {
err = PTR_ERR(type);
xenbus_dev_fatal(dev, err, "reading type");
goto out;
}
err = xenbus_printf(xbt, dev->nodename, "feature-discard",
"%d", state);
if (err)
xenbus_dev_fatal(dev, err, "writing feature-discard");
kfree:
kfree(type);
out:
return err;
}
int xen_blkbk_barrier(struct xenbus_transaction xbt,
struct backend_info *be, int state)
{
struct xenbus_device *dev = be->dev;
int err;
err = xenbus_printf(xbt, dev->nodename, "feature-barrier",
"%d", state);
if (err)
xenbus_dev_fatal(dev, err, "writing feature-barrier");
return err;
}
/* /*
* Entry point to this code when a new device is created. Allocate the basic * Entry point to this code when a new device is created. Allocate the basic
* structures, and watch the store waiting for the hotplug scripts to tell us * structures, and watch the store waiting for the hotplug scripts to tell us
...@@ -590,7 +661,7 @@ static void frontend_changed(struct xenbus_device *dev, ...@@ -590,7 +661,7 @@ static void frontend_changed(struct xenbus_device *dev,
/* /*
* Enforce precondition before potential leak point. * Enforce precondition before potential leak point.
* blkif_disconnect() is idempotent. * xen_blkif_disconnect() is idempotent.
*/ */
xen_blkif_disconnect(be->blkif); xen_blkif_disconnect(be->blkif);
...@@ -611,7 +682,7 @@ static void frontend_changed(struct xenbus_device *dev, ...@@ -611,7 +682,7 @@ static void frontend_changed(struct xenbus_device *dev,
break; break;
/* fall through if not online */ /* fall through if not online */
case XenbusStateUnknown: case XenbusStateUnknown:
/* implies blkif_disconnect() via blkback_remove() */ /* implies xen_blkif_disconnect() via xen_blkbk_remove() */
device_unregister(&dev->dev); device_unregister(&dev->dev);
break; break;
...@@ -650,6 +721,11 @@ static void connect(struct backend_info *be) ...@@ -650,6 +721,11 @@ static void connect(struct backend_info *be)
if (err) if (err)
goto abort; goto abort;
err = xen_blkbk_discard(xbt, be);
/* If we can't advertise it is OK. */
err = xen_blkbk_barrier(xbt, be, be->blkif->vbd.flush_support);
err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu", err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
(unsigned long long)vbd_sz(&be->blkif->vbd)); (unsigned long long)vbd_sz(&be->blkif->vbd));
if (err) { if (err) {
......
...@@ -98,6 +98,9 @@ struct blkfront_info ...@@ -98,6 +98,9 @@ struct blkfront_info
unsigned long shadow_free; unsigned long shadow_free;
unsigned int feature_flush; unsigned int feature_flush;
unsigned int flush_op; unsigned int flush_op;
unsigned int feature_discard;
unsigned int discard_granularity;
unsigned int discard_alignment;
int is_ready; int is_ready;
}; };
...@@ -302,6 +305,12 @@ static int blkif_queue_request(struct request *req) ...@@ -302,6 +305,12 @@ static int blkif_queue_request(struct request *req)
ring_req->operation = info->flush_op; ring_req->operation = info->flush_op;
} }
if (unlikely(req->cmd_flags & REQ_DISCARD)) {
/* id, sector_number and handle are set above. */
ring_req->operation = BLKIF_OP_DISCARD;
ring_req->nr_segments = 0;
ring_req->u.discard.nr_sectors = blk_rq_sectors(req);
} else {
ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg); ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST); BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
...@@ -317,7 +326,7 @@ static int blkif_queue_request(struct request *req) ...@@ -317,7 +326,7 @@ static int blkif_queue_request(struct request *req)
ref, ref,
info->xbdev->otherend_id, info->xbdev->otherend_id,
buffer_mfn, buffer_mfn,
rq_data_dir(req) ); rq_data_dir(req));
info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn); info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
ring_req->u.rw.seg[i] = ring_req->u.rw.seg[i] =
...@@ -326,6 +335,7 @@ static int blkif_queue_request(struct request *req) ...@@ -326,6 +335,7 @@ static int blkif_queue_request(struct request *req)
.first_sect = fsect, .first_sect = fsect,
.last_sect = lsect }; .last_sect = lsect };
} }
}
info->ring.req_prod_pvt++; info->ring.req_prod_pvt++;
...@@ -370,7 +380,9 @@ static void do_blkif_request(struct request_queue *rq) ...@@ -370,7 +380,9 @@ static void do_blkif_request(struct request_queue *rq)
blk_start_request(req); blk_start_request(req);
if (req->cmd_type != REQ_TYPE_FS) { if ((req->cmd_type != REQ_TYPE_FS) ||
((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) &&
!info->flush_op)) {
__blk_end_request_all(req, -EIO); __blk_end_request_all(req, -EIO);
continue; continue;
} }
...@@ -399,6 +411,7 @@ static void do_blkif_request(struct request_queue *rq) ...@@ -399,6 +411,7 @@ static void do_blkif_request(struct request_queue *rq)
static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size) static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
{ {
struct request_queue *rq; struct request_queue *rq;
struct blkfront_info *info = gd->private_data;
rq = blk_init_queue(do_blkif_request, &blkif_io_lock); rq = blk_init_queue(do_blkif_request, &blkif_io_lock);
if (rq == NULL) if (rq == NULL)
...@@ -406,6 +419,13 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size) ...@@ -406,6 +419,13 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
queue_flag_set_unlocked(QUEUE_FLAG_VIRT, rq); queue_flag_set_unlocked(QUEUE_FLAG_VIRT, rq);
if (info->feature_discard) {
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, rq);
blk_queue_max_discard_sectors(rq, get_capacity(gd));
rq->limits.discard_granularity = info->discard_granularity;
rq->limits.discard_alignment = info->discard_alignment;
}
/* Hard sector size and max sectors impersonate the equiv. hardware. */ /* Hard sector size and max sectors impersonate the equiv. hardware. */
blk_queue_logical_block_size(rq, sector_size); blk_queue_logical_block_size(rq, sector_size);
blk_queue_max_hw_sectors(rq, 512); blk_queue_max_hw_sectors(rq, 512);
...@@ -722,6 +742,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id) ...@@ -722,6 +742,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
error = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO; error = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO;
switch (bret->operation) { switch (bret->operation) {
case BLKIF_OP_DISCARD:
if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
struct request_queue *rq = info->rq;
printk(KERN_WARNING "blkfront: %s: discard op failed\n",
info->gd->disk_name);
error = -EOPNOTSUPP;
info->feature_discard = 0;
queue_flag_clear(QUEUE_FLAG_DISCARD, rq);
}
__blk_end_request_all(req, error);
break;
case BLKIF_OP_FLUSH_DISKCACHE: case BLKIF_OP_FLUSH_DISKCACHE:
case BLKIF_OP_WRITE_BARRIER: case BLKIF_OP_WRITE_BARRIER:
if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) { if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
...@@ -1098,6 +1129,33 @@ blkfront_closing(struct blkfront_info *info) ...@@ -1098,6 +1129,33 @@ blkfront_closing(struct blkfront_info *info)
bdput(bdev); bdput(bdev);
} }
static void blkfront_setup_discard(struct blkfront_info *info)
{
int err;
char *type;
unsigned int discard_granularity;
unsigned int discard_alignment;
type = xenbus_read(XBT_NIL, info->xbdev->otherend, "type", NULL);
if (IS_ERR(type))
return;
if (strncmp(type, "phy", 3) == 0) {
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"discard-granularity", "%u", &discard_granularity,
"discard-alignment", "%u", &discard_alignment,
NULL);
if (!err) {
info->feature_discard = 1;
info->discard_granularity = discard_granularity;
info->discard_alignment = discard_alignment;
}
} else if (strncmp(type, "file", 4) == 0)
info->feature_discard = 1;
kfree(type);
}
/* /*
* Invoked when the backend is finally 'ready' (and has told produced * Invoked when the backend is finally 'ready' (and has told produced
* the details about the physical device - #sectors, size, etc). * the details about the physical device - #sectors, size, etc).
...@@ -1108,7 +1166,7 @@ static void blkfront_connect(struct blkfront_info *info) ...@@ -1108,7 +1166,7 @@ static void blkfront_connect(struct blkfront_info *info)
unsigned long sector_size; unsigned long sector_size;
unsigned int binfo; unsigned int binfo;
int err; int err;
int barrier, flush; int barrier, flush, discard;
switch (info->connected) { switch (info->connected) {
case BLKIF_STATE_CONNECTED: case BLKIF_STATE_CONNECTED:
...@@ -1179,6 +1237,13 @@ static void blkfront_connect(struct blkfront_info *info) ...@@ -1179,6 +1237,13 @@ static void blkfront_connect(struct blkfront_info *info)
info->flush_op = BLKIF_OP_FLUSH_DISKCACHE; info->flush_op = BLKIF_OP_FLUSH_DISKCACHE;
} }
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"feature-discard", "%d", &discard,
NULL);
if (!err && discard)
blkfront_setup_discard(info);
err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size); err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size);
if (err) { if (err) {
xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s", xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s",
...@@ -1385,6 +1450,8 @@ static struct xenbus_driver blkfront = { ...@@ -1385,6 +1450,8 @@ static struct xenbus_driver blkfront = {
static int __init xlblk_init(void) static int __init xlblk_init(void)
{ {
int ret;
if (!xen_domain()) if (!xen_domain())
return -ENODEV; return -ENODEV;
...@@ -1394,7 +1461,13 @@ static int __init xlblk_init(void) ...@@ -1394,7 +1461,13 @@ static int __init xlblk_init(void)
return -ENODEV; return -ENODEV;
} }
return xenbus_register_frontend(&blkfront); ret = xenbus_register_frontend(&blkfront);
if (ret) {
unregister_blkdev(XENVBD_MAJOR, DEV_NAME);
return ret;
}
return 0;
} }
module_init(xlblk_init); module_init(xlblk_init);
......
...@@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t; ...@@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t;
* "feature-flush-cache" node! * "feature-flush-cache" node!
*/ */
#define BLKIF_OP_FLUSH_DISKCACHE 3 #define BLKIF_OP_FLUSH_DISKCACHE 3
/*
* Recognised only if "feature-discard" is present in backend xenbus info.
* The "feature-discard" node contains a boolean indicating whether trim
* (ATA) or unmap (SCSI) - conviently called discard requests are likely
* to succeed or fail. Either way, a discard request
* may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
* the underlying block-device hardware. The boolean simply indicates whether
* or not it is worthwhile for the frontend to attempt discard requests.
* If a backend does not recognise BLKIF_OP_DISCARD, it should *not*
* create the "feature-discard" node!
*
* Discard operation is a request for the underlying block device to mark
* extents to be erased. However, discard does not guarantee that the blocks
* will be erased from the device - it is just a hint to the device
* controller that these blocks are no longer in use. What the device
* controller does with that information is left to the controller.
* Discard operations are passed with sector_number as the
* sector index to begin discard operations at and nr_sectors as the number of
* sectors to be discarded. The specified sectors should be discarded if the
* underlying block device supports trim (ATA) or unmap (SCSI) operations,
* or a BLKIF_RSP_EOPNOTSUPP should be returned.
* More information about trim/unmap operations at:
* http://t13.org/Documents/UploadedDocuments/docs2008/
* e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc
* http://www.seagate.com/staticfiles/support/disc/manuals/
* Interface%20manuals/100293068c.pdf
*/
#define BLKIF_OP_DISCARD 5
/* /*
* Maximum scatter/gather segments per request. * Maximum scatter/gather segments per request.
* This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE. * This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE.
...@@ -74,6 +104,11 @@ struct blkif_request_rw { ...@@ -74,6 +104,11 @@ struct blkif_request_rw {
} seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; } seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
}; };
struct blkif_request_discard {
blkif_sector_t sector_number;
uint64_t nr_sectors;
};
struct blkif_request { struct blkif_request {
uint8_t operation; /* BLKIF_OP_??? */ uint8_t operation; /* BLKIF_OP_??? */
uint8_t nr_segments; /* number of segments */ uint8_t nr_segments; /* number of segments */
...@@ -81,6 +116,7 @@ struct blkif_request { ...@@ -81,6 +116,7 @@ struct blkif_request {
uint64_t id; /* private guest value, echoed in resp */ uint64_t id; /* private guest value, echoed in resp */
union { union {
struct blkif_request_rw rw; struct blkif_request_rw rw;
struct blkif_request_discard discard;
} u; } u;
}; };
......
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