treewide: Switch/rename to timer_delete[_sync]()

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with c

treewide: Switch/rename to timer_delete[_sync]()

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

scsi: target: tcmu: Constify some structures

'struct nla_policy' and 'struct match_table_t' are not modified in this
driver.

Constifying these structures moves some data to a read-only section, so

scsi: target: tcmu: Constify some structures

'struct nla_policy' and 'struct match_table_t' are not modified in this
driver.

Constifying these structures moves some data to a read-only section, so
increase overall security, especially when the structure holds some
function pointers, which is the case of struct nla_policy.

On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
93188 6933 338 100459 1886b drivers/target/target_core_user.o

After:
=====
text data bss dec hex filename
93508 6581 338 100427 1884b drivers/target/target_core_user.o

Signed-off-by: Christophe JAILLET <[email protected]>
Link: https://lore.kernel.org/r/f83cd8469cc17391178e1181e8c26c4c1fb6028f.1731330634.git.christophe.jaillet@wanadoo.fr
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

genetlink: hold RCU in genlmsg_mcast()

While running net selftests with CONFIG_PROVE_RCU_LIST=y I saw
one lockdep splat [1].

genlmsg_mcast() uses for_each_net_rcu(), and must therefore hold RCU.

I

genetlink: hold RCU in genlmsg_mcast()

While running net selftests with CONFIG_PROVE_RCU_LIST=y I saw
one lockdep splat [1].

genlmsg_mcast() uses for_each_net_rcu(), and must therefore hold RCU.

Instead of letting all callers guard genlmsg_multicast_allns()
with a rcu_read_lock()/rcu_read_unlock() pair, do it in genlmsg_mcast().

This also means the @flags parameter is useless, we need to always use
GFP_ATOMIC.

[1]
[10882.424136] =============================
[10882.424166] WARNING: suspicious RCU usage
[10882.424309] 6.12.0-rc2-virtme #1156 Not tainted
[10882.424400] -----------------------------
[10882.424423] net/netlink/genetlink.c:1940 RCU-list traversed in non-reader section!!
[10882.424469]
other info that might help us debug this:

[10882.424500]
rcu_scheduler_active = 2, debug_locks = 1
[10882.424744] 2 locks held by ip/15677:
[10882.424791] #0: ffffffffb6b491b0 (cb_lock){++++}-{3:3}, at: genl_rcv (net/netlink/genetlink.c:1219)
[10882.426334] #1: ffffffffb6b49248 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg (net/netlink/genetlink.c:61 net/netlink/genetlink.c:57 net/netlink/genetlink.c:1209)
[10882.426465]
stack backtrace:
[10882.426805] CPU: 14 UID: 0 PID: 15677 Comm: ip Not tainted 6.12.0-rc2-virtme #1156
[10882.426919] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[10882.427046] Call Trace:
[10882.427131] <TASK>
[10882.427244] dump_stack_lvl (lib/dump_stack.c:123)
[10882.427335] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822)
[10882.427387] genlmsg_multicast_allns (net/netlink/genetlink.c:1940 (discriminator 7) net/netlink/genetlink.c:1977 (discriminator 7))
[10882.427436] l2tp_tunnel_notify.constprop.0 (net/l2tp/l2tp_netlink.c:119) l2tp_netlink
[10882.427683] l2tp_nl_cmd_tunnel_create (net/l2tp/l2tp_netlink.c:253) l2tp_netlink
[10882.427748] genl_family_rcv_msg_doit (net/netlink/genetlink.c:1115)
[10882.427834] genl_rcv_msg (net/netlink/genetlink.c:1195 net/netlink/genetlink.c:1210)
[10882.427877] ? __pfx_l2tp_nl_cmd_tunnel_create (net/l2tp/l2tp_netlink.c:186) l2tp_netlink
[10882.427927] ? __pfx_genl_rcv_msg (net/netlink/genetlink.c:1201)
[10882.427959] netlink_rcv_skb (net/netlink/af_netlink.c:2551)
[10882.428069] genl_rcv (net/netlink/genetlink.c:1220)
[10882.428095] netlink_unicast (net/netlink/af_netlink.c:1332 net/netlink/af_netlink.c:1357)
[10882.428140] netlink_sendmsg (net/netlink/af_netlink.c:1901)
[10882.428210] ____sys_sendmsg (net/socket.c:729 (discriminator 1) net/socket.c:744 (discriminator 1) net/socket.c:2607 (discriminator 1))

Fixes: 33f72e6f0c67 ("l2tp : multicast notification to the registered listeners")
Signed-off-by: Eric Dumazet <[email protected]>
Cc: James Chapman <[email protected]>
Cc: Tom Parkin <[email protected]>
Cc: Johannes Berg <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

scsi: target: tcmu: Annotate struct tcmu_tmr with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_b

scsi: target: tcmu: Annotate struct tcmu_tmr with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct tcmu_tmr.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Bodo Stroesser <[email protected]>
Cc: "Martin K. Petersen" <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: "Gustavo A. R. Silva" <[email protected]>
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Replace strlcpy() with strscpy()

strlcpy() reads the entire source buffer first. This read may exceed the
destination size limit. This is both inefficient and can lead to linea

scsi: target: tcmu: Replace strlcpy() with strscpy()

strlcpy() reads the entire source buffer first. This read may exceed the
destination size limit. This is both inefficient and can lead to linear
read overflows if a source string is not NUL-terminated [1]. In an effort
to remove strlcpy() completely [2], replace strlcpy() here with strscpy().

No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

mm: replace vma->vm_flags direct modifications with modifier calls

Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma loc

mm: replace vma->vm_flags direct modifications with modifier calls

Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness.

[[email protected]: fix drivers/misc/open-dice.c, per Hyeonggon Yoo]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Mel Gorman <[email protected]>
Acked-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Sebastian Reichel <[email protected]>
Reviewed-by: Liam R. Howlett <[email protected]>
Reviewed-by: Hyeonggon Yoo <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arjun Roy <[email protected]>
Cc: Axel Rasmussen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: David Howells <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Greg Thelen <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Joel Fernandes <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Laurent Dufour <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Oskolkov <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Punit Agrawal <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: Soheil Hassas Yeganeh <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

genetlink: start to validate reserved header bytes

We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use ca

genetlink: start to validate reserved header bytes

We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.

To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.

Signed-off-by: Jakub Kicinski <[email protected]>
Acked-by: Paul Moore <[email protected]> (NetLabel)
Signed-off-by: David S. Miller <[email protected]>

show more ...

scsi: target: tcmu: Avoid holding XArray lock when calling lock_page

In tcmu_blocks_release(), lock_page() is called to prevent a race causing
possible data corruption. Since lock_page() might sleep

scsi: target: tcmu: Avoid holding XArray lock when calling lock_page

In tcmu_blocks_release(), lock_page() is called to prevent a race causing
possible data corruption. Since lock_page() might sleep, calling it while
holding XArray lock is a bug.

To fix this, replace the xas_for_each() call with xa_for_each_range().
Since the latter does its own handling of XArray locking, the xas_lock()
and xas_unlock() calls around the original loop are no longer necessary.

The switch to xa_for_each_range() slows down the loop slightly. This is
acceptable since tcmu_blocks_release() is not relevant for performance.

Link: https://lore.kernel.org/r/[email protected]
Fixes: bb9b9eb0ae2e ("scsi: target: tcmu: Fix possible data corruption")
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Fix possible data corruption

When tcmu_vma_fault() gets a page successfully, before the current context
completes page fault procedure, find_free_blocks() may run and call
unmap_

scsi: target: tcmu: Fix possible data corruption

When tcmu_vma_fault() gets a page successfully, before the current context
completes page fault procedure, find_free_blocks() may run and call
unmap_mapping_range() to unmap the page. Assume that when
find_free_blocks() initially completes and the previous page fault
procedure starts to run again and completes, then one truncated page has
been mapped to userspace. But note that tcmu_vma_fault() has gotten a
refcount for the page so any other subsystem won't be able to use the page
unless the userspace address is unmapped later.

If another command subsequently runs and needs to extend dbi_thresh it may
reuse the corresponding slot for the previous page in data_bitmap. Then
though we'll allocate new page for this slot in data_area, no page fault
will happen because we have a valid map and the real request's data will be
lost.

Filesystem implementations will also run into this issue but they usually
lock the page when vm_operations_struct->fault gets a page and unlock the
page after finish_fault() completes. For truncate filesystems lock pages in
truncate_inode_pages() to protect against racing wrt. page faults.

To fix this possible data corruption scenario we can apply a method similar
to the filesystems. For pages that are to be freed, tcmu_blocks_release()
locks and unlocks. Make tcmu_vma_fault() also lock found page under
cmdr_lock. At the same time, since tcmu_vma_fault() gets an extra page
refcount, tcmu_blocks_release() won't free pages if pages are in page fault
procedure, which means it is safe to call tcmu_blocks_release() before
unmap_mapping_range().

With these changes tcmu_blocks_release() will wait for all page faults to
be completed before calling unmap_mapping_range(). And later, if
unmap_mapping_range() is called, it will ensure stale mappings are removed.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Xiaoguang Wang <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Fix possible page UAF

tcmu_try_get_data_page() looks up pages under cmdr_lock, but it does not
take refcount properly and just returns page pointer. When
tcmu_try_get_data_page()

scsi: target: tcmu: Fix possible page UAF

tcmu_try_get_data_page() looks up pages under cmdr_lock, but it does not
take refcount properly and just returns page pointer. When
tcmu_try_get_data_page() returns, the returned page may have been freed by
tcmu_blocks_release().

We need to get_page() under cmdr_lock to avoid concurrent
tcmu_blocks_release().

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Xiaoguang Wang <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Make cmd_ring_size changeable via configfs

Make cmd_ring_size changeable similar to the way it is done for
max_data_area_mb. The reason is that our tcmu client will create thousa

scsi: target: tcmu: Make cmd_ring_size changeable via configfs

Make cmd_ring_size changeable similar to the way it is done for
max_data_area_mb. The reason is that our tcmu client will create thousands
of tcmu instances, and this will consume lots of mem with default 8Mb cmd
ring size for every backstore.

One can change the value by typing:

echo "cmd_ring_size_mb=N" > control

The "N" is a integer between 1 to 8, if set 1, the cmd ring can hold about
6k cmds(tcmu_cmd_entry about 176 byte) at least.

The value is printed when doing:

cat info

In addition, a new readonly attribute 'cmd_ring_size_mb' returns the value
in read.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Xiaoguang Wang <[email protected]>
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Guixin Liu <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Allocate zeroed pages for data area

Tcmu populates the data area (used for communication with userspace) with
pages that are allocated by calling alloc_page(GFP_NOIO). Therefore

scsi: target: tcmu: Allocate zeroed pages for data area

Tcmu populates the data area (used for communication with userspace) with
pages that are allocated by calling alloc_page(GFP_NOIO). Therefore
previous content of the allocated pages is exposed to user space. Avoid
this by adding __GFP_ZERO flag.

Zeroing the pages does (nearly) not affect tcmu throughput, because
allocated pages are re-used for the data transfers of later SCSI cmds.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Use struct_size() helper in kmalloc()

Make use of the struct_size() helper instead of an open-coded version, in
order to avoid any potential type mistakes or integer overflows th

scsi: target: tcmu: Use struct_size() helper in kmalloc()

Make use of the struct_size() helper instead of an open-coded version, in
order to avoid any potential type mistakes or integer overflows that, in
the worst scenario, could lead to heap overflows.

Link: https://github.com/KSPP/linux/issues/160
Link: https://lore.kernel.org/r/20210927224344.GA190701@embeddedor
Reviewed-by: Bodo Stroesser <[email protected]>
Signed-off-by: Gustavo A. R. Silva <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Add new feature KEEP_BUF

When running command pipelining for WRITE direction commands (e.g. tape
device write), userspace sends cmd completion to cmd ring before processing
write

scsi: target: tcmu: Add new feature KEEP_BUF

When running command pipelining for WRITE direction commands (e.g. tape
device write), userspace sends cmd completion to cmd ring before processing
write data. In that case userspace has to copy data before sending
completion, because cmd completion also implicitly releases the data buffer
in data area.

The new feature KEEP_BUF allows userspace to optionally keep the buffer
after completion by setting new bit TCMU_UFLAG_KEEP_BUF in
tcmu_cmd_entry_hdr->uflags. In that case buffer has to be released
explicitly by writing the cmd_id to new action item free_kept_buf.

All kept buffers are released during reset_ring and if userspace closes uio
device (tcmu_release).

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Fix boolreturn.cocci warnings

drivers/target/target_core_user.c:1424:9-10: WARNING: return of 0/1 in function 'tcmu_handle_completions' with return type bool

Return statements

scsi: target: tcmu: Fix boolreturn.cocci warnings

drivers/target/target_core_user.c:1424:9-10: WARNING: return of 0/1 in function 'tcmu_handle_completions' with return type bool

Return statements in functions returning bool should use
true/false instead of 1/0.

Generated by: scripts/coccinelle/misc/boolreturn.cocci

Link: https://lore.kernel.org/r/20210515230358.GA97544@60d1edce16e0
Fixes: 9814b55cde05 ("scsi: target: tcmu: Return from tcmu_handle_completions() if cmd_id not found")
CC: Bodo Stroesser <[email protected]>
Reported-by: kernel test robot <[email protected]>
Acked-by: Bodo Stroesser <[email protected]>
Signed-off-by: kernel test robot <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Fix xarray RCU warning

Commit f5ce815f34bc ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N *
PAGE_SIZE") introduced xas_next() calls to iterate xarray elements. These
calls tr

scsi: target: tcmu: Fix xarray RCU warning

Commit f5ce815f34bc ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N *
PAGE_SIZE") introduced xas_next() calls to iterate xarray elements. These
calls triggered the WARNING "suspicious RCU usage" at tcmu device set up
[1]. In the call stack of xas_next(), xas_load() was called. According to
its comment, this function requires "the xa_lock or the RCU lock".

To avoid the warning:

- Guard the small loop calling xas_next() in tcmu_get_empty_block with RCU
lock.

- In the large loop in tcmu_copy_data using RCU lock would possibly
disable preemtion for a long time (copy multi MBs). Therefore replace
XA_STATE, xas_set and xas_next with a single xa_load.

[1]

[ 1899.867091] =============================
[ 1899.871199] WARNING: suspicious RCU usage
[ 1899.875310] 5.13.0-rc1+ #41 Not tainted
[ 1899.879222] -----------------------------
[ 1899.883299] include/linux/xarray.h:1182 suspicious rcu_dereference_check() usage!
[ 1899.890940] other info that might help us debug this:
[ 1899.899082] rcu_scheduler_active = 2, debug_locks = 1
[ 1899.905719] 3 locks held by kworker/0:1/1368:
[ 1899.910161] #0: ffffa1f8c8b98738 ((wq_completion)target_submission){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580
[ 1899.920732] #1: ffffbd7040cd7e78 ((work_completion)(&q->sq.work)){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580
[ 1899.931146] #2: ffffa1f8d1c99768 (&udev->cmdr_lock){+.+.}-{3:3}, at: tcmu_queue_cmd+0xea/0x160 [target_core_user]
[ 1899.941678] stack backtrace:
[ 1899.946093] CPU: 0 PID: 1368 Comm: kworker/0:1 Not tainted 5.13.0-rc1+ #41
[ 1899.953070] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 1302 03/15/2018
[ 1899.962459] Workqueue: target_submission target_queued_submit_work [target_core_mod]
[ 1899.970337] Call Trace:
[ 1899.972839] dump_stack+0x6d/0x89
[ 1899.976222] xas_descend+0x10e/0x120
[ 1899.979875] xas_load+0x39/0x50
[ 1899.983077] tcmu_get_empty_blocks+0x115/0x1c0 [target_core_user]
[ 1899.989318] queue_cmd_ring+0x1da/0x630 [target_core_user]
[ 1899.994897] ? rcu_read_lock_sched_held+0x3f/0x70
[ 1899.999695] ? trace_kmalloc+0xa6/0xd0
[ 1900.003501] ? __kmalloc+0x205/0x380
[ 1900.007167] tcmu_queue_cmd+0x12f/0x160 [target_core_user]
[ 1900.012746] __target_execute_cmd+0x23/0xa0 [target_core_mod]
[ 1900.018589] transport_generic_new_cmd+0x1f3/0x370 [target_core_mod]
[ 1900.025046] transport_handle_cdb_direct+0x34/0x50 [target_core_mod]
[ 1900.031517] target_queued_submit_work+0x43/0xe0 [target_core_mod]
[ 1900.037837] process_one_work+0x268/0x580
[ 1900.041952] ? process_one_work+0x580/0x580
[ 1900.046195] worker_thread+0x55/0x3b0
[ 1900.049921] ? process_one_work+0x580/0x580
[ 1900.054192] kthread+0x143/0x160
[ 1900.057499] ? kthread_create_worker_on_cpu+0x40/0x40
[ 1900.062661] ret_from_fork+0x1f/0x30

Link: https://lore.kernel.org/r/[email protected]
Fixes: f5ce815f34bc ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE")
Reported-by: Shin'ichiro Kawasaki <[email protected]>
Tested-by: Shin'ichiro Kawasaki <[email protected]>
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Rename TCM_DEV_BIT_PLUGGED to TCMU_DEV_BIT_PLUGGED

The bit definition TCM_DEV_BIT_PLUGGED should correctly be named
TCMU_DEV_BIT_PLUGGED, since all other bits in the same bitfiel

scsi: target: tcmu: Rename TCM_DEV_BIT_PLUGGED to TCMU_DEV_BIT_PLUGGED

The bit definition TCM_DEV_BIT_PLUGGED should correctly be named
TCMU_DEV_BIT_PLUGGED, since all other bits in the same bitfield have prefix
TCMU_.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

show more ...

scsi: target: tcmu: Return from tcmu_handle_completions() if cmd_id not found

If tcmu_handle_completions() finds an invalid cmd_id while looping over cmd
responses from userspace it sets TCMU_DEV_BI

scsi: target: tcmu: Return from tcmu_handle_completions() if cmd_id not found

If tcmu_handle_completions() finds an invalid cmd_id while looping over cmd
responses from userspace it sets TCMU_DEV_BIT_BROKEN and breaks the
loop. This means that it does further handling for the tcmu device.

Skip that handling by replacing 'break' with 'return'.

Additionally change tcmu_handle_completions() from unsigned int to bool,
since the value used in return already is bool.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Make data_pages_per_blk changeable via configfs

Make data_pages_per_blk changeable similar to the way it is done for
max_data_area_mb. One can change the value by typing:

echo

scsi: target: tcmu: Make data_pages_per_blk changeable via configfs

Make data_pages_per_blk changeable similar to the way it is done for
max_data_area_mb. One can change the value by typing:

echo "data_pages_per_blk=N" >control

The value is printed when doing:

cat info

In addition, a new readonly attribute 'data_pages_per_blk' returns the
value on read.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Replace block size definitions with new udev members

Replace DATA_PAGES_PER_BLK and DATA_BLOCK_SIZE with new struct elements
tcmu_dev->data_pages_per_blk and tcmu_dev->data_blk_s

scsi: target: tcmu: Replace block size definitions with new udev members

Replace DATA_PAGES_PER_BLK and DATA_BLOCK_SIZE with new struct elements
tcmu_dev->data_pages_per_blk and tcmu_dev->data_blk_size. These new
variables are still loaded with constant definition DATA_PAGES_PER_BLK_DEF
(= 1) and DATA_PAGES_PER_BLK_DEF * PAGE_SIZE.

There is no way yet to set the values via configfs.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Remove function tcmu_get_block_page()

There is only one caller of tcmu_get_block_page left. Since it is a
one-liner, we can remove the function.

Link: https://lore.kernel.org/r/

scsi: target: tcmu: Remove function tcmu_get_block_page()

There is only one caller of tcmu_get_block_page left. Since it is a
one-liner, we can remove the function.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE

Change tcmu to support DATA_BLOCK_SIZE being a multiple of PAGE_SIZE. There
are two reasons why one would like to have a bigger DATA_BLOCK

scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE

Change tcmu to support DATA_BLOCK_SIZE being a multiple of PAGE_SIZE. There
are two reasons why one would like to have a bigger DATA_BLOCK_SIZE:

1) If userspace - e.g. due to data compression, encryption or
deduplication - needs to have receive or transmit data in a consecutive
buffer, we can define DATA_BLOCK_SIZE to the maximum size of a SCSI
READ/WRITE to enforce that userspace sees just one consecutive
buffer. That way we can avoid the need for doing data copy in
userspace.

2) Using a bigger data block size can speed up command processing in
tcmu. The number of free data blocks to look up in bitmap is reduced
substantially. The lookup for data pages in radix_tree can be done more
efficiently if there are multiple pages in a data block. The maximum
number of IOVs to set up is lower so cmd entries in the ring become
smaller.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Prepare for PAGE_SIZE != DATA_BLOCK_SIZE

Rename some variables and definitions as a first preparation for
DATA_BLOCK_SIZE != PAGE_SIZE and add the new DATA_PAGES_PER_BLK definiti

scsi: target: tcmu: Prepare for PAGE_SIZE != DATA_BLOCK_SIZE

Rename some variables and definitions as a first preparation for
DATA_BLOCK_SIZE != PAGE_SIZE and add the new DATA_PAGES_PER_BLK definition
containing the number of pages per data block.

Rename tcmu_try_get_block_page() to tcmu_try_get_data_page(). Keep name
tcmu_get_block_page() since it will go away in a following commit when
there is only one caller left. Subsequent commits will then add full
support for DATA_PAGES_PER_BLK != 1, which also means DATA_BLOCK_SIZE =
DATA_PAGES_PER_BLK * PAGE_SIZE

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Adjust names of variables and definitions

Some definitions and members of struct tcmu_dev had misleading
names. Examples:

- ring_size was used for the size of mailbox + cmd rin

scsi: target: tcmu: Adjust names of variables and definitions

Some definitions and members of struct tcmu_dev had misleading
names. Examples:

- ring_size was used for the size of mailbox + cmd ring + data area

- CMDR_SIZE was used for size of mailbox + cmd ring

I added the new definition MB_CMDR_SIZE (mailbox + command ring), changed
CMDR_SIZE to hold the size of the command ring only and replaced in struct
tcmu_dev the member ring_size with mmap_pages, because the member is now
used in tcmu_mmap() only, where we need page count, not size.

I also added the new struct tcmu_dev member 'cmdr' which is used to replace
some occurences of '(void *)mb + CMDR_OFF' with 'udev->cmdr' for better
readability.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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scsi: target: tcmu: Adjust parameter in call to tcmu_blocks_release()

In commit f7c89771d07d ("scsi: target: tcmu: Replace radix_tree with
XArray") the meaning of last parameter of tcmu_blocks_relea

scsi: target: tcmu: Adjust parameter in call to tcmu_blocks_release()

In commit f7c89771d07d ("scsi: target: tcmu: Replace radix_tree with
XArray") the meaning of last parameter of tcmu_blocks_release() was
changed. So in the callers we should subtract 1 from the previous
parameter.

Unfortunately that change got lost at one of the two places where
tcmu_blocks_release() is called. That does not lead to any problems, but we
should adjust it anyway.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bodo Stroesser <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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