d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

nvme: Fix alignment on nvme structures

Browse Source 
Remove __packed from nvme_command, nvme_completion and
nvme_dsm_trim. Add super-alignment to nvme_completion since it's always
at least that aligned in hardware (and in our existing uses of it
embedded in structures). It generates better code in
nvme_qpair_process_completions on riscv64 because otherwise the ABI
assumes a 4-byte alignment, and the same on all other platforms.

Reviewed by:		jrtc27@, mav@, chuck@
Sponsored by:		Netflix
Differential Revision:	https://reviews.freebsd.org/D31001
This commit is contained in:
Warner Losh 2021-07-02 15:58:19 -06:00
parent 80a75155e1
commit fea3cf1d6d
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
sys/dev/nvme/nvme.h
View File

@ -578,8 +578,8 @@ struct nvme_registers {
struct {
uint32_t sq_tdbl; /* submission queue tail doorbell */
uint32_t cq_hdbl; /* completion queue head doorbell */
} doorbell[1] __packed;
} __packed;
} doorbell[1];
};
_Static_assert(sizeof(struct nvme_registers) == 0x1008, "bad size for nvme_registers");
@ -612,7 +612,7 @@ struct nvme_command {
uint32_t cdw13; /* command-specific */
uint32_t cdw14; /* command-specific */
uint32_t cdw15; /* command-specific */
} __packed;
};
_Static_assert(sizeof(struct nvme_command) == 16 * 4, "bad size for nvme_command");
@ -630,7 +630,7 @@ struct nvme_completion {
/* dword 3 */
uint16_t cid; /* command identifier */
uint16_t status;
} __packed;
} __aligned(8); /* riscv: nvme_qpair_process_completions has better code gen */
_Static_assert(sizeof(struct nvme_completion) == 4 * 4, "bad size for nvme_completion");
@ -638,7 +638,7 @@ struct nvme_dsm_range {
uint32_t attributes;
uint32_t length;
uint64_t starting_lba;
} __packed;
};
/* Largest DSM Trim that can be done */
#define NVME_MAX_DSM_TRIM 4096